All_Problems.md

# LeetCode Solutions — Complete Problem Directory

A continuously updated collection of **LeetCode solutions, DSA problems, algorithms, data structures, coding interview questions, and programming solutions**.

Each problem includes its **problem number, title, difficulty, algorithmic pattern, programming language, time complexity, space complexity, source code, and explanation**.

## Quick Navigation

### Statistics

- **Total Solved:** 1125+
- **Easy:** 509+
- **Medium:** 409+
- **Hard:** 207+

### Browse by Difficulty

- [Easy Problems](difficulty/easy.md)
- [Medium Problems](difficulty/medium.md)
- [Hard Problems](difficulty/hard.md)

### Browse by Algorithm

- [Binary Search](patterns/binary-search.md)
- [Sliding Window](patterns/sliding-window.md)
- [Two Pointers](patterns/two-pointers.md)
- [Hash Map](patterns/hash-map.md)
- [Dynamic Programming](patterns/dynamic-programming.md)
- [Greedy](patterns/greedy.md)
- [Monotonic Stack](patterns/monotonic-stack.md)
- [Backtracking](patterns/backtracking.md)
- [Graph & Tree](patterns/tree-graph.md)
- [SQL / Database](patterns/sql-database.md)
- [Math & Logic](patterns/math-logic.md)

## Complete Problem Directory

| # | Problem | Difficulty | Pattern | Language | Algorithm | Time | Space | Code | Explanation |
|---|---|---|---|---|---|---|---|---|---|
| 1 | [Two Sum](leetcode/0001-two-sum/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0001-two-sum/) | [Explanation](leetcode/0001-two-sum/Explanation.md) |
| 2 | [Add Two Numbers](leetcode/0002-add-two-numbers/) | Medium | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0002-add-two-numbers/) | [Explanation](leetcode/0002-add-two-numbers/Explanation.md) |
| 3 | [Longest Substring Without Repeating Characters](leetcode/0003-longest-substring-without-repeating-characters/) | Medium | [Sliding Window](patterns/sliding-window.md) | Python | Dynamic Sliding Window Traversal | O(n) | O(1) | [Code](leetcode/0003-longest-substring-without-repeating-characters/) | [Explanation](leetcode/0003-longest-substring-without-repeating-characters/Explanation.md) |
| 4 | [Median of Two Sorted Arrays](leetcode/0004-median-of-two-sorted-arrays/) | Hard | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0004-median-of-two-sorted-arrays/) | [Explanation](leetcode/0004-median-of-two-sorted-arrays/Explanation.md) |
| 5 | [Longest Palindromic Substring](leetcode/0005-longest-palindromic-substring/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0005-longest-palindromic-substring/) | [Explanation](leetcode/0005-longest-palindromic-substring/Explanation.md) |
| 6 | [Zigzag Conversion](leetcode/0006-zigzag-conversion/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0006-zigzag-conversion/) | [Explanation](leetcode/0006-zigzag-conversion/Explanation.md) |
| 7 | [Reverse Integer](leetcode/0007-reverse-integer/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | JavaScript | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0007-reverse-integer/) | [Explanation](leetcode/0007-reverse-integer/Explanation.md) |
| 8 | [String to Integer (atoi)](leetcode/0008-string-to-integer-atoi/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0008-string-to-integer-atoi/) | [Explanation](leetcode/0008-string-to-integer-atoi/Explanation.md) |
| 9 | [Palindrome Number](leetcode/0009-palindrome-number/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0009-palindrome-number/) | [Explanation](leetcode/0009-palindrome-number/Explanation.md) |
| 10 | [Regular Expression Matching](leetcode/0010-regular-expression-matching/) | Hard | [Dynamic Programming](patterns/dynamic-programming.md) | JavaScript | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/0010-regular-expression-matching/) | [Explanation](leetcode/0010-regular-expression-matching/Explanation.md) |
| 11 | [Container With Most Water](leetcode/0011-container-with-most-water/) | Medium | [Two Pointers](patterns/two-pointers.md) | JavaScript | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0011-container-with-most-water/) | [Explanation](leetcode/0011-container-with-most-water/Explanation.md) |
| 12 | [Integer to Roman](leetcode/0012-integer-to-roman/) | Medium | [Heap](patterns/heap.md) | JavaScript | Min/Max Heap Priority Selection | O(n) | O(n) | [Code](leetcode/0012-integer-to-roman/) | [Explanation](leetcode/0012-integer-to-roman/Explanation.md) |
| 13 | [Roman to Integer](leetcode/0013-roman-to-integer/) | Easy | [Prefix Sum](patterns/prefix-sum.md) | Python | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/0013-roman-to-integer/) | [Explanation](leetcode/0013-roman-to-integer/Explanation.md) |
| 14 | [Longest Common Prefix](leetcode/0014-longest-common-prefix/) | Easy | [Prefix Sum](patterns/prefix-sum.md) | Python | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/0014-longest-common-prefix/) | [Explanation](leetcode/0014-longest-common-prefix/Explanation.md) |
| 15 | [3Sum](leetcode/0015-3sum/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(log n) | O(1) | [Code](leetcode/0015-3sum/) | [Explanation](leetcode/0015-3sum/Explanation.md) |
| 16 | [3Sum Closest](leetcode/0016-3sum-closest/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(log n) | O(1) | [Code](leetcode/0016-3sum-closest/) | [Explanation](leetcode/0016-3sum-closest/Explanation.md) |
| 17 | [Letter Combinations of a Phone Number](leetcode/0017-letter-combinations-of-a-phone-number/) | Medium | [Backtracking](patterns/backtracking.md) | JavaScript | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/0017-letter-combinations-of-a-phone-number/) | [Explanation](leetcode/0017-letter-combinations-of-a-phone-number/Explanation.md) |
| 18 | [4Sum](leetcode/0018-4sum/) | Medium | [Binary Search](patterns/binary-search.md) | C++ | Modified Binary Search | O(log n) | O(1) | [Code](leetcode/0018-4sum/) | [Explanation](leetcode/0018-4sum/Explanation.md) |
| 19 | [Remove Nth Node From End of List](leetcode/0019-remove-nth-node-from-end-of-list/) | Medium | [Fast & Slow Pointers](patterns/fast-slow-pointers.md) | JavaScript | Floyd Cycle Detection | O(n) | O(1) | [Code](leetcode/0019-remove-nth-node-from-end-of-list/) | [Explanation](leetcode/0019-remove-nth-node-from-end-of-list/Explanation.md) |
| 20 | [Valid Parentheses](leetcode/0020-valid-parentheses/) | Easy | [Stack & Queue](patterns/stack-queue.md) | JavaScript | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/0020-valid-parentheses/) | [Explanation](leetcode/0020-valid-parentheses/Explanation.md) |
| 21 | [Merge Two Sorted Lists](leetcode/0021-merge-two-sorted-lists/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0021-merge-two-sorted-lists/) | [Explanation](leetcode/0021-merge-two-sorted-lists/Explanation.md) |
| 22 | [Generate Parentheses](leetcode/0022-generate-parentheses/) | Medium | [Stack & Queue](patterns/stack-queue.md) | C++ | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/0022-generate-parentheses/) | [Explanation](leetcode/0022-generate-parentheses/Explanation.md) |
| 23 | [Merge k Sorted Lists](leetcode/0023-merge-k-sorted-lists/) | Hard | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0023-merge-k-sorted-lists/) | [Explanation](leetcode/0023-merge-k-sorted-lists/Explanation.md) |
| 24 | [Swap Nodes in Pairs](leetcode/0024-swap-nodes-in-pairs/) | Medium | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0024-swap-nodes-in-pairs/) | [Explanation](leetcode/0024-swap-nodes-in-pairs/Explanation.md) |
| 25 | [Reverse Nodes in k-Group](leetcode/0025-reverse-nodes-in-k-group/) | Hard | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0025-reverse-nodes-in-k-group/) | [Explanation](leetcode/0025-reverse-nodes-in-k-group/Explanation.md) |
| 26 | [Remove Duplicates from Sorted Array](leetcode/0026-remove-duplicates-from-sorted-array/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0026-remove-duplicates-from-sorted-array/) | [Explanation](leetcode/0026-remove-duplicates-from-sorted-array/Explanation.md) |
| 27 | [Remove Element](leetcode/0027-remove-element/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0027-remove-element/) | [Explanation](leetcode/0027-remove-element/Explanation.md) |
| 28 | [Find the Index of the First Occurrence in a String](leetcode/0028-find-the-index-of-the-first-occurrence-in-a-string/) | Easy | [Stack & Queue](patterns/stack-queue.md) | Python | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/0028-find-the-index-of-the-first-occurrence-in-a-string/) | [Explanation](leetcode/0028-find-the-index-of-the-first-occurrence-in-a-string/Explanation.md) |
| 29 | [Divide Two Integers](leetcode/0029-divide-two-integers/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0029-divide-two-integers/) | [Explanation](leetcode/0029-divide-two-integers/Explanation.md) |
| 30 | [Substring with Concatenation of All Words](leetcode/0030-substring-with-concatenation-of-all-words/) | Hard | [Sliding Window](patterns/sliding-window.md) | Python | Dynamic Sliding Window Traversal | O(n) | O(1) | [Code](leetcode/0030-substring-with-concatenation-of-all-words/) | [Explanation](leetcode/0030-substring-with-concatenation-of-all-words/Explanation.md) |
| 31 | [Next Permutation](leetcode/0031-next-permutation/) | Medium | [Backtracking](patterns/backtracking.md) | Python | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/0031-next-permutation/) | [Explanation](leetcode/0031-next-permutation/Explanation.md) |
| 32 | [Longest Valid Parentheses](leetcode/0032-longest-valid-parentheses/) | Hard | [Stack & Queue](patterns/stack-queue.md) | Python | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/0032-longest-valid-parentheses/) | [Explanation](leetcode/0032-longest-valid-parentheses/Explanation.md) |
| 33 | [Search in Rotated Sorted Array](leetcode/0033-search-in-rotated-sorted-array/) | Medium | [Binary Search](patterns/binary-search.md) | C++, Python | Modified Binary Search | O(log n) | O(1) | [Code](leetcode/0033-search-in-rotated-sorted-array/) | [Explanation](leetcode/0033-search-in-rotated-sorted-array/Explanation.md) |
| 34 | [Find First and Last Position of Element in Sorted Array](leetcode/0034-find-first-and-last-position-of-element-in-sorted-array/) | Medium | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(log n) | O(1) | [Code](leetcode/0034-find-first-and-last-position-of-element-in-sorted-array/) | [Explanation](leetcode/0034-find-first-and-last-position-of-element-in-sorted-array/Explanation.md) |
| 35 | [Search Insert Position](leetcode/0035-search-insert-position/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(log n) | O(1) | [Code](leetcode/0035-search-insert-position/) | [Explanation](leetcode/0035-search-insert-position/Explanation.md) |
| 36 | [Valid Sudoku](leetcode/0036-valid-sudoku/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0036-valid-sudoku/) | [Explanation](leetcode/0036-valid-sudoku/Explanation.md) |
| 37 | [Sudoku Solver](leetcode/0037-sudoku-solver/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0037-sudoku-solver/) | [Explanation](leetcode/0037-sudoku-solver/Explanation.md) |
| 38 | [Count and Say](leetcode/0038-count-and-say/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0038-count-and-say/) | [Explanation](leetcode/0038-count-and-say/Explanation.md) |
| 39 | [Combination Sum](leetcode/0039-combination-sum/) | Medium | [Backtracking](patterns/backtracking.md) | Python | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/0039-combination-sum/) | [Explanation](leetcode/0039-combination-sum/Explanation.md) |
| 40 | [Combination Sum II](leetcode/0040-combination-sum-ii/) | Medium | [Backtracking](patterns/backtracking.md) | Python | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/0040-combination-sum-ii/) | [Explanation](leetcode/0040-combination-sum-ii/Explanation.md) |
| 41 | [First Missing Positive](leetcode/0041-first-missing-positive/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0041-first-missing-positive/) | [Explanation](leetcode/0041-first-missing-positive/Explanation.md) |
| 42 | [Trapping Rain Water](leetcode/0042-trapping-rain-water/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0042-trapping-rain-water/) | [Explanation](leetcode/0042-trapping-rain-water/Explanation.md) |
| 43 | [Multiply Strings](leetcode/0043-multiply-strings/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0043-multiply-strings/) | [Explanation](leetcode/0043-multiply-strings/Explanation.md) |
| 44 | [Wildcard Matching](leetcode/0044-wildcard-matching/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0044-wildcard-matching/) | [Explanation](leetcode/0044-wildcard-matching/Explanation.md) |
| 45 | [Jump Game II](leetcode/0045-jump-game-ii/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0045-jump-game-ii/) | [Explanation](leetcode/0045-jump-game-ii/Explanation.md) |
| 46 | [Permutations](leetcode/0046-permutations/) | Medium | [Backtracking](patterns/backtracking.md) | Python | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/0046-permutations/) | [Explanation](leetcode/0046-permutations/Explanation.md) |
| 47 | [Permutations II](leetcode/0047-permutations-ii/) | Medium | [Backtracking](patterns/backtracking.md) | Python | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/0047-permutations-ii/) | [Explanation](leetcode/0047-permutations-ii/Explanation.md) |
| 48 | [Rotate Image](leetcode/0048-rotate-image/) | Medium | [Math & Logic](patterns/math-logic.md) | C++ | Mathematical Simulation & Modular Arithmetic | O(n²) | O(1) | [Code](leetcode/0048-rotate-image/) | [Explanation](leetcode/0048-rotate-image/Explanation.md) |
| 49 | [Group Anagrams](leetcode/0049-group-anagrams/) | Medium | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0049-group-anagrams/) | [Explanation](leetcode/0049-group-anagrams/Explanation.md) |
| 50 | [Pow(x, n)](leetcode/0050-powx-n/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0050-powx-n/) | [Explanation](leetcode/0050-powx-n/Explanation.md) |
| 51 | [N-Queens](leetcode/0051-n-queens/) | Hard | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0051-n-queens/) | [Explanation](leetcode/0051-n-queens/Explanation.md) |
| 52 | [N-Queens II](leetcode/0052-n-queens-ii/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0052-n-queens-ii/) | [Explanation](leetcode/0052-n-queens-ii/Explanation.md) |
| 53 | [Maximum Subarray](leetcode/0053-maximum-subarray/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0053-maximum-subarray/) | [Explanation](leetcode/0053-maximum-subarray/Explanation.md) |
| 54 | [Spiral Matrix](leetcode/0054-spiral-matrix/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0054-spiral-matrix/) | [Explanation](leetcode/0054-spiral-matrix/Explanation.md) |
| 55 | [Jump Game](leetcode/0055-jump-game/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0055-jump-game/) | [Explanation](leetcode/0055-jump-game/Explanation.md) |
| 56 | [Merge Intervals](leetcode/0056-merge-intervals/) | Medium | [Heap](patterns/heap.md) | Python | Min/Max Heap Priority Selection | O(n) | O(n) | [Code](leetcode/0056-merge-intervals/) | [Explanation](leetcode/0056-merge-intervals/Explanation.md) |
| 57 | [Insert Interval](leetcode/0057-insert-interval/) | Medium | [Heap](patterns/heap.md) | Python | Min/Max Heap Priority Selection | O(n) | O(n) | [Code](leetcode/0057-insert-interval/) | [Explanation](leetcode/0057-insert-interval/Explanation.md) |
| 58 | [Length of Last Word](leetcode/0058-length-of-last-word/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0058-length-of-last-word/) | [Explanation](leetcode/0058-length-of-last-word/Explanation.md) |
| 59 | [Spiral Matrix II](leetcode/0059-spiral-matrix-ii/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0059-spiral-matrix-ii/) | [Explanation](leetcode/0059-spiral-matrix-ii/Explanation.md) |
| 60 | [Permutation Sequence](leetcode/0060-permutation-sequence/) | Hard | [Backtracking](patterns/backtracking.md) | Python | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/0060-permutation-sequence/) | [Explanation](leetcode/0060-permutation-sequence/Explanation.md) |
| 61 | [Rotate List](leetcode/0061-rotate-list/) | Medium | [Two Pointers](patterns/two-pointers.md) | C++ | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0061-rotate-list/) | [Explanation](leetcode/0061-rotate-list/Explanation.md) |
| 62 | [Unique Paths](leetcode/0062-unique-paths/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript, Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0062-unique-paths/) | [Explanation](leetcode/0062-unique-paths/Explanation.md) |
| 63 | [Unique Paths II](leetcode/0063-unique-paths-ii/) | Medium | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0063-unique-paths-ii/) | [Explanation](leetcode/0063-unique-paths-ii/Explanation.md) |
| 64 | [Minimum Path Sum](leetcode/0064-minimum-path-sum/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0064-minimum-path-sum/) | [Explanation](leetcode/0064-minimum-path-sum/Explanation.md) |
| 65 | [Valid Number](leetcode/0065-valid-number/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0065-valid-number/) | [Explanation](leetcode/0065-valid-number/Explanation.md) |
| 66 | [Plus One](leetcode/0066-plus-one/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0066-plus-one/) | [Explanation](leetcode/0066-plus-one/Explanation.md) |
| 67 | [Add Binary](leetcode/0067-add-binary/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0067-add-binary/) | [Explanation](leetcode/0067-add-binary/Explanation.md) |
| 68 | [Text Justification](leetcode/0068-text-justification/) | Hard | [Heap](patterns/heap.md) | Python | Min/Max Heap Priority Selection | O(n) | O(n) | [Code](leetcode/0068-text-justification/) | [Explanation](leetcode/0068-text-justification/Explanation.md) |
| 69 | [Sqrt(x)](leetcode/0069-sqrtx/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0069-sqrtx/) | [Explanation](leetcode/0069-sqrtx/Explanation.md) |
| 70 | [Climbing Stairs](leetcode/0070-climbing-stairs/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0070-climbing-stairs/) | [Explanation](leetcode/0070-climbing-stairs/Explanation.md) |
| 71 | [Simplify Path](leetcode/0071-simplify-path/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0071-simplify-path/) | [Explanation](leetcode/0071-simplify-path/Explanation.md) |
| 72 | [Edit Distance](leetcode/0072-edit-distance/) | Medium | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0072-edit-distance/) | [Explanation](leetcode/0072-edit-distance/Explanation.md) |
| 73 | [Set Matrix Zeroes](leetcode/0073-set-matrix-zeroes/) | Medium | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0073-set-matrix-zeroes/) | [Explanation](leetcode/0073-set-matrix-zeroes/Explanation.md) |
| 74 | [Search a 2D Matrix](leetcode/0074-search-a-2d-matrix/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0074-search-a-2d-matrix/) | [Explanation](leetcode/0074-search-a-2d-matrix/Explanation.md) |
| 75 | [Sort Colors](leetcode/0075-sort-colors/) | Medium | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0075-sort-colors/) | [Explanation](leetcode/0075-sort-colors/Explanation.md) |
| 76 | [Minimum Window Substring](leetcode/0076-minimum-window-substring/) | Hard | [Sliding Window](patterns/sliding-window.md) | PHP | Dynamic Sliding Window Traversal | O(n) | O(1) | [Code](leetcode/0076-minimum-window-substring/) | [Explanation](leetcode/0076-minimum-window-substring/Explanation.md) |
| 77 | [Combinations](leetcode/0077-combinations/) | Medium | [Backtracking](patterns/backtracking.md) | PHP | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/0077-combinations/) | [Explanation](leetcode/0077-combinations/Explanation.md) |
| 78 | [Subsets](leetcode/0078-subsets/) | Medium | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0078-subsets/) | [Explanation](leetcode/0078-subsets/Explanation.md) |
| 79 | [Word Search](leetcode/0079-word-search/) | Medium | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0079-word-search/) | [Explanation](leetcode/0079-word-search/Explanation.md) |
| 80 | [Remove Duplicates from Sorted Array II](leetcode/0080-remove-duplicates-from-sorted-array-ii/) | Medium | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0080-remove-duplicates-from-sorted-array-ii/) | [Explanation](leetcode/0080-remove-duplicates-from-sorted-array-ii/Explanation.md) |
| 81 | [Search in Rotated Sorted Array II](leetcode/0081-search-in-rotated-sorted-array-ii/) | Medium | [Binary Search](patterns/binary-search.md) | PHP | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0081-search-in-rotated-sorted-array-ii/) | [Explanation](leetcode/0081-search-in-rotated-sorted-array-ii/Explanation.md) |
| 82 | [Remove Duplicates from Sorted List II](leetcode/0082-remove-duplicates-from-sorted-list-ii/) | Medium | [Two Pointers](patterns/two-pointers.md) | PHP | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0082-remove-duplicates-from-sorted-list-ii/) | [Explanation](leetcode/0082-remove-duplicates-from-sorted-list-ii/Explanation.md) |
| 83 | [Remove Duplicates from Sorted List](leetcode/0083-remove-duplicates-from-sorted-list/) | Easy | [Two Pointers](patterns/two-pointers.md) | PHP, Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0083-remove-duplicates-from-sorted-list/) | [Explanation](leetcode/0083-remove-duplicates-from-sorted-list/Explanation.md) |
| 84 | [Largest Rectangle in Histogram](leetcode/0084-largest-rectangle-in-histogram/) | Hard | [Monotonic Stack](patterns/monotonic-stack.md) | TypeScript | Monotonic Stack Filtering | O(n) | O(n) | [Code](leetcode/0084-largest-rectangle-in-histogram/) | [Explanation](leetcode/0084-largest-rectangle-in-histogram/Explanation.md) |
| 85 | [Maximal Rectangle](leetcode/0085-maximal-rectangle/) | Hard | [Math & Logic](patterns/math-logic.md) | Python | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0085-maximal-rectangle/) | [Explanation](leetcode/0085-maximal-rectangle/Explanation.md) |
| 86 | [Partition List](leetcode/0086-partition-list/) | Medium | [Two Pointers](patterns/two-pointers.md) | JavaScript | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0086-partition-list/) | [Explanation](leetcode/0086-partition-list/Explanation.md) |
| 87 | [Scramble String](leetcode/0087-scramble-string/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0087-scramble-string/) | [Explanation](leetcode/0087-scramble-string/Explanation.md) |
| 88 | [Merge Sorted Array](leetcode/0088-merge-sorted-array/) | Easy | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0088-merge-sorted-array/) | [Explanation](leetcode/0088-merge-sorted-array/Explanation.md) |
| 89 | [Gray Code](leetcode/0089-gray-code/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | JavaScript, Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0089-gray-code/) | [Explanation](leetcode/0089-gray-code/Explanation.md) |
| 90 | [Subsets II](leetcode/0090-subsets-ii/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0090-subsets-ii/) | [Explanation](leetcode/0090-subsets-ii/Explanation.md) |
| 91 | [Decode Ways](leetcode/0091-decode-ways/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | JavaScript | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0091-decode-ways/) | [Explanation](leetcode/0091-decode-ways/Explanation.md) |
| 92 | [Reverse Linked List II](leetcode/0092-reverse-linked-list-ii/) | Medium | [Two Pointers](patterns/two-pointers.md) | JavaScript | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0092-reverse-linked-list-ii/) | [Explanation](leetcode/0092-reverse-linked-list-ii/Explanation.md) |
| 93 | [Restore IP Addresses](leetcode/0093-restore-ip-addresses/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0093-restore-ip-addresses/) | [Explanation](leetcode/0093-restore-ip-addresses/Explanation.md) |
| 94 | [Binary Tree Inorder Traversal](leetcode/0094-binary-tree-inorder-traversal/) | Easy | [Binary Search](patterns/binary-search.md) | PHP | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0094-binary-tree-inorder-traversal/) | [Explanation](leetcode/0094-binary-tree-inorder-traversal/Explanation.md) |
| 95 | [Unique Binary Search Trees II](leetcode/0095-unique-binary-search-trees-ii/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0095-unique-binary-search-trees-ii/) | [Explanation](leetcode/0095-unique-binary-search-trees-ii/Explanation.md) |
| 96 | [Unique Binary Search Trees](leetcode/0096-unique-binary-search-trees/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0096-unique-binary-search-trees/) | [Explanation](leetcode/0096-unique-binary-search-trees/Explanation.md) |
| 97 | [Interleaving String](leetcode/0097-interleaving-string/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0097-interleaving-string/) | [Explanation](leetcode/0097-interleaving-string/Explanation.md) |
| 98 | [Validate Binary Search Tree](leetcode/0098-validate-binary-search-tree/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0098-validate-binary-search-tree/) | [Explanation](leetcode/0098-validate-binary-search-tree/Explanation.md) |
| 99 | [Recover Binary Search Tree](leetcode/0099-recover-binary-search-tree/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0099-recover-binary-search-tree/) | [Explanation](leetcode/0099-recover-binary-search-tree/Explanation.md) |
| 100 | [Same Tree](leetcode/0100-same-tree/) | Easy | [Binary Search](patterns/binary-search.md) | PHP | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0100-same-tree/) | [Explanation](leetcode/0100-same-tree/Explanation.md) |
| 101 | [Symmetric Tree](leetcode/0101-symmetric-tree/) | Easy | [Binary Search](patterns/binary-search.md) | PHP | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0101-symmetric-tree/) | [Explanation](leetcode/0101-symmetric-tree/Explanation.md) |
| 102 | [Binary Tree Level Order Traversal](leetcode/0102-binary-tree-level-order-traversal/) | Medium | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0102-binary-tree-level-order-traversal/) | [Explanation](leetcode/0102-binary-tree-level-order-traversal/Explanation.md) |
| 103 | [Binary Tree Zigzag Level Order Traversal](leetcode/0103-binary-tree-zigzag-level-order-traversal/) | Medium | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0103-binary-tree-zigzag-level-order-traversal/) | [Explanation](leetcode/0103-binary-tree-zigzag-level-order-traversal/Explanation.md) |
| 104 | [Maximum Depth of Binary Tree](leetcode/0104-maximum-depth-of-binary-tree/) | Easy | [Binary Search](patterns/binary-search.md) | JavaScript, PHP | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0104-maximum-depth-of-binary-tree/) | [Explanation](leetcode/0104-maximum-depth-of-binary-tree/Explanation.md) |
| 105 | [Construct Binary Tree from Preorder and Inorder Traversal](leetcode/0105-construct-binary-tree-from-preorder-and-inorder-traversal/) | Medium | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0105-construct-binary-tree-from-preorder-and-inorder-traversal/) | [Explanation](leetcode/0105-construct-binary-tree-from-preorder-and-inorder-traversal/Explanation.md) |
| 106 | [Construct Binary Tree from Inorder and Postorder Traversal](leetcode/0106-construct-binary-tree-from-inorder-and-postorder-traversal/) | Medium | [Tree & Graph](patterns/tree-graph.md) | JavaScript, Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0106-construct-binary-tree-from-inorder-and-postorder-traversal/) | [Explanation](leetcode/0106-construct-binary-tree-from-inorder-and-postorder-traversal/Explanation.md) |
| 108 | [Convert Sorted Array to Binary Search Tree](leetcode/0108-convert-sorted-array-to-binary-search-tree/) | Easy | [Binary Search](patterns/binary-search.md) | PHP | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0108-convert-sorted-array-to-binary-search-tree/) | [Explanation](leetcode/0108-convert-sorted-array-to-binary-search-tree/Explanation.md) |
| 109 | [Convert Sorted List to Binary Search Tree](leetcode/0109-convert-sorted-list-to-binary-search-tree/) | Medium | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0109-convert-sorted-list-to-binary-search-tree/) | [Explanation](leetcode/0109-convert-sorted-list-to-binary-search-tree/Explanation.md) |
| 110 | [Balanced Binary Tree](leetcode/0110-balanced-binary-tree/) | Easy | [Binary Search](patterns/binary-search.md) | PHP | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0110-balanced-binary-tree/) | [Explanation](leetcode/0110-balanced-binary-tree/Explanation.md) |
| 111 | [Minimum Depth of Binary Tree](leetcode/0111-minimum-depth-of-binary-tree/) | Easy | [Binary Search](patterns/binary-search.md) | PHP | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0111-minimum-depth-of-binary-tree/) | [Explanation](leetcode/0111-minimum-depth-of-binary-tree/Explanation.md) |
| 112 | [Path Sum](leetcode/0112-path-sum/) | Easy | [Tree & Graph](patterns/tree-graph.md) | PHP | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0112-path-sum/) | [Explanation](leetcode/0112-path-sum/Explanation.md) |
| 114 | [Flatten Binary Tree to Linked List](leetcode/0114-flatten-binary-tree-to-linked-list/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0114-flatten-binary-tree-to-linked-list/) | [Explanation](leetcode/0114-flatten-binary-tree-to-linked-list/Explanation.md) |
| 115 | [Distinct Subsequences](leetcode/0115-distinct-subsequences/) | Hard | [Dynamic Programming](patterns/dynamic-programming.md) | JavaScript | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/0115-distinct-subsequences/) | [Explanation](leetcode/0115-distinct-subsequences/Explanation.md) |
| 117 | [Populating Next Right Pointers in Each Node II](leetcode/0117-populating-next-right-pointers-in-each-node-ii/) | Medium | [Stack & Queue](patterns/stack-queue.md) | JavaScript | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/0117-populating-next-right-pointers-in-each-node-ii/) | [Explanation](leetcode/0117-populating-next-right-pointers-in-each-node-ii/Explanation.md) |
| 118 | [Pascal's Triangle](leetcode/0118-pascals-triangle/) | Easy | [Math & Logic](patterns/math-logic.md) | PHP, Python | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0118-pascals-triangle/) | [Explanation](leetcode/0118-pascals-triangle/Explanation.md) |
| 119 | [Pascal's Triangle II](leetcode/0119-pascals-triangle-ii/) | Easy | [Math & Logic](patterns/math-logic.md) | PHP | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0119-pascals-triangle-ii/) | [Explanation](leetcode/0119-pascals-triangle-ii/Explanation.md) |
| 120 | [Triangle](leetcode/0120-triangle/) | Medium | [Math & Logic](patterns/math-logic.md) | JavaScript | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0120-triangle/) | [Explanation](leetcode/0120-triangle/Explanation.md) |
| 121 | [Best Time to Buy and Sell Stock](leetcode/0121-best-time-to-buy-and-sell-stock/) | Easy | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0121-best-time-to-buy-and-sell-stock/) | [Explanation](leetcode/0121-best-time-to-buy-and-sell-stock/Explanation.md) |
| 122 | [Best Time to Buy and Sell Stock II](leetcode/0122-best-time-to-buy-and-sell-stock-ii/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0122-best-time-to-buy-and-sell-stock-ii/) | [Explanation](leetcode/0122-best-time-to-buy-and-sell-stock-ii/Explanation.md) |
| 123 | [Best Time to Buy and Sell Stock III](leetcode/0123-best-time-to-buy-and-sell-stock-iii/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0123-best-time-to-buy-and-sell-stock-iii/) | [Explanation](leetcode/0123-best-time-to-buy-and-sell-stock-iii/Explanation.md) |
| 124 | [Binary Tree Maximum Path Sum](leetcode/0124-binary-tree-maximum-path-sum/) | Hard | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0124-binary-tree-maximum-path-sum/) | [Explanation](leetcode/0124-binary-tree-maximum-path-sum/Explanation.md) |
| 125 | [Valid Palindrome](leetcode/0125-valid-palindrome/) | Easy | [Two Pointers](patterns/two-pointers.md) | PHP | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0125-valid-palindrome/) | [Explanation](leetcode/0125-valid-palindrome/Explanation.md) |
| 126 | [Word Ladder II](leetcode/0126-word-ladder-ii/) | Hard | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0126-word-ladder-ii/) | [Explanation](leetcode/0126-word-ladder-ii/Explanation.md) |
| 127 | [Word Ladder](leetcode/0127-word-ladder/) | Hard | [Hash Map](patterns/hash-map.md) | JavaScript | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0127-word-ladder/) | [Explanation](leetcode/0127-word-ladder/Explanation.md) |
| 128 | [Longest Consecutive Sequence](leetcode/0128-longest-consecutive-sequence/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0128-longest-consecutive-sequence/) | [Explanation](leetcode/0128-longest-consecutive-sequence/Explanation.md) |
| 129 | [Sum Root to Leaf Numbers](leetcode/0129-sum-root-to-leaf-numbers/) | Medium | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0129-sum-root-to-leaf-numbers/) | [Explanation](leetcode/0129-sum-root-to-leaf-numbers/Explanation.md) |
| 130 | [Surrounded Regions](leetcode/0130-surrounded-regions/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0130-surrounded-regions/) | [Explanation](leetcode/0130-surrounded-regions/Explanation.md) |
| 131 | [Palindrome Partitioning](leetcode/0131-palindrome-partitioning/) | Medium | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0131-palindrome-partitioning/) | [Explanation](leetcode/0131-palindrome-partitioning/Explanation.md) |
| 133 | [Clone Graph](leetcode/0133-clone-graph/) | Medium | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0133-clone-graph/) | [Explanation](leetcode/0133-clone-graph/Explanation.md) |
| 134 | [Gas Station](leetcode/0134-gas-station/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0134-gas-station/) | [Explanation](leetcode/0134-gas-station/Explanation.md) |
| 135 | [Candy](leetcode/0135-candy/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0135-candy/) | [Explanation](leetcode/0135-candy/Explanation.md) |
| 136 | [Single Number](leetcode/0136-single-number/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, PHP, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0136-single-number/) | [Explanation](leetcode/0136-single-number/Explanation.md) |
| 137 | [Single Number II](leetcode/0137-single-number-ii/) | Medium | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0137-single-number-ii/) | [Explanation](leetcode/0137-single-number-ii/Explanation.md) |
| 138 | [Copy List with Random Pointer](leetcode/0138-copy-list-with-random-pointer/) | Medium | [Two Pointers](patterns/two-pointers.md) | JavaScript, Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0138-copy-list-with-random-pointer/) | [Explanation](leetcode/0138-copy-list-with-random-pointer/Explanation.md) |
| 139 | [Word Break](leetcode/0139-word-break/) | Medium | [Hash Map](patterns/hash-map.md) | JavaScript | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0139-word-break/) | [Explanation](leetcode/0139-word-break/Explanation.md) |
| 140 | [Word Break II](leetcode/0140-word-break-ii/) | Hard | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0140-word-break-ii/) | [Explanation](leetcode/0140-word-break-ii/Explanation.md) |
| 141 | [Linked List Cycle](leetcode/0141-linked-list-cycle/) | Easy | [Fast & Slow Pointers](patterns/fast-slow-pointers.md) | PHP | Floyd Cycle Detection | O(n) | O(1) | [Code](leetcode/0141-linked-list-cycle/) | [Explanation](leetcode/0141-linked-list-cycle/Explanation.md) |
| 142 | [Linked List Cycle II](leetcode/0142-linked-list-cycle-ii/) | Medium | [Fast & Slow Pointers](patterns/fast-slow-pointers.md) | Python | Floyd Cycle Detection | O(n) | O(1) | [Code](leetcode/0142-linked-list-cycle-ii/) | [Explanation](leetcode/0142-linked-list-cycle-ii/Explanation.md) |
| 144 | [Binary Tree Preorder Traversal](leetcode/0144-binary-tree-preorder-traversal/) | Easy | [Tree & Graph](patterns/tree-graph.md) | PHP | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0144-binary-tree-preorder-traversal/) | [Explanation](leetcode/0144-binary-tree-preorder-traversal/Explanation.md) |
| 145 | [Binary Tree Postorder Traversal](leetcode/0145-binary-tree-postorder-traversal/) | Easy | [Tree & Graph](patterns/tree-graph.md) | PHP | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0145-binary-tree-postorder-traversal/) | [Explanation](leetcode/0145-binary-tree-postorder-traversal/Explanation.md) |
| 146 | [LRU Cache](leetcode/0146-lru-cache/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0146-lru-cache/) | [Explanation](leetcode/0146-lru-cache/Explanation.md) |
| 147 | [Insertion Sort List](leetcode/0147-insertion-sort-list/) | Medium | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0147-insertion-sort-list/) | [Explanation](leetcode/0147-insertion-sort-list/Explanation.md) |
| 148 | [Sort List](leetcode/0148-sort-list/) | Medium | [Two Pointers](patterns/two-pointers.md) | JavaScript | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0148-sort-list/) | [Explanation](leetcode/0148-sort-list/Explanation.md) |
| 149 | [Max Points on a Line](leetcode/0149-max-points-on-a-line/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0149-max-points-on-a-line/) | [Explanation](leetcode/0149-max-points-on-a-line/Explanation.md) |
| 150 | [Evaluate Reverse Polish Notation](leetcode/0150-evaluate-reverse-polish-notation/) | Medium | [Stack & Queue](patterns/stack-queue.md) | TypeScript | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/0150-evaluate-reverse-polish-notation/) | [Explanation](leetcode/0150-evaluate-reverse-polish-notation/Explanation.md) |
| 151 | [Reverse Words in a String](leetcode/0151-reverse-words-in-a-string/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0151-reverse-words-in-a-string/) | [Explanation](leetcode/0151-reverse-words-in-a-string/Explanation.md) |
| 152 | [Maximum Product Subarray](leetcode/0152-maximum-product-subarray/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0152-maximum-product-subarray/) | [Explanation](leetcode/0152-maximum-product-subarray/Explanation.md) |
| 153 | [Find Minimum in Rotated Sorted Array](leetcode/0153-find-minimum-in-rotated-sorted-array/) | Medium | [Binary Search](patterns/binary-search.md) | C++ | Modified Binary Search | O(log n) | O(1) | [Code](leetcode/0153-find-minimum-in-rotated-sorted-array/) | [Explanation](leetcode/0153-find-minimum-in-rotated-sorted-array/Explanation.md) |
| 154 | [Find Minimum in Rotated Sorted Array II](leetcode/0154-find-minimum-in-rotated-sorted-array-ii/) | Hard | [Binary Search](patterns/binary-search.md) | C++ | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0154-find-minimum-in-rotated-sorted-array-ii/) | [Explanation](leetcode/0154-find-minimum-in-rotated-sorted-array-ii/Explanation.md) |
| 155 | [Min Stack](leetcode/0155-min-stack/) | Medium | [Stack & Queue](patterns/stack-queue.md) | JavaScript | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/0155-min-stack/) | [Explanation](leetcode/0155-min-stack/Explanation.md) |
| 160 | [Intersection of Two Linked Lists](leetcode/0160-intersection-of-two-linked-lists/) | Easy | [Two Pointers](patterns/two-pointers.md) | PHP | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0160-intersection-of-two-linked-lists/) | [Explanation](leetcode/0160-intersection-of-two-linked-lists/Explanation.md) |
| 162 | [Find Peak Element](leetcode/0162-find-peak-element/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(log n) | O(1) | [Code](leetcode/0162-find-peak-element/) | [Explanation](leetcode/0162-find-peak-element/Explanation.md) |
| 167 | [Two Sum Ii   Input Array Is Sorted](leetcode/0167-two-sum-ii---input-array-is-sorted/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0167-two-sum-ii---input-array-is-sorted/) | [Explanation](leetcode/0167-two-sum-ii---input-array-is-sorted/Explanation.md) |
| 168 | [Excel Sheet Column Title](leetcode/0168-excel-sheet-column-title/) | Easy | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0168-excel-sheet-column-title/) | [Explanation](leetcode/0168-excel-sheet-column-title/Explanation.md) |
| 169 | [Majority Element](leetcode/0169-majority-element/) | Easy | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0169-majority-element/) | [Explanation](leetcode/0169-majority-element/Explanation.md) |
| 171 | [Excel Sheet Column Number](leetcode/0171-excel-sheet-column-number/) | Easy | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0171-excel-sheet-column-number/) | [Explanation](leetcode/0171-excel-sheet-column-number/Explanation.md) |
| 172 | [Factorial Trailing Zeroes](leetcode/0172-factorial-trailing-zeroes/) | Medium | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0172-factorial-trailing-zeroes/) | [Explanation](leetcode/0172-factorial-trailing-zeroes/Explanation.md) |
| 173 | [Binary Search Tree Iterator](leetcode/0173-binary-search-tree-iterator/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0173-binary-search-tree-iterator/) | [Explanation](leetcode/0173-binary-search-tree-iterator/Explanation.md) |
| 175 | [Combine Two Tables](leetcode/0175-combine-two-tables/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0175-combine-two-tables/) | [Explanation](leetcode/0175-combine-two-tables/Explanation.md) |
| 176 | [Second Highest Salary](leetcode/0176-second-highest-salary/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0176-second-highest-salary/) | [Explanation](leetcode/0176-second-highest-salary/Explanation.md) |
| 177 | [Nth Highest Salary](leetcode/0177-nth-highest-salary/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0177-nth-highest-salary/) | [Explanation](leetcode/0177-nth-highest-salary/Explanation.md) |
| 178 | [Rank Scores](leetcode/0178-rank-scores/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0178-rank-scores/) | [Explanation](leetcode/0178-rank-scores/Explanation.md) |
| 180 | [Consecutive Numbers](leetcode/0180-consecutive-numbers/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0180-consecutive-numbers/) | [Explanation](leetcode/0180-consecutive-numbers/Explanation.md) |
| 181 | [Employees Earning More Than Their Managers](leetcode/0181-employees-earning-more-than-their-managers/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0181-employees-earning-more-than-their-managers/) | [Explanation](leetcode/0181-employees-earning-more-than-their-managers/Explanation.md) |
| 182 | [Duplicate Emails](leetcode/0182-duplicate-emails/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0182-duplicate-emails/) | [Explanation](leetcode/0182-duplicate-emails/Explanation.md) |
| 183 | [Customers Who Never Order](leetcode/0183-customers-who-never-order/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0183-customers-who-never-order/) | [Explanation](leetcode/0183-customers-who-never-order/Explanation.md) |
| 184 | [Department Highest Salary](leetcode/0184-department-highest-salary/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0184-department-highest-salary/) | [Explanation](leetcode/0184-department-highest-salary/Explanation.md) |
| 185 | [Department Top Three Salaries](leetcode/0185-department-top-three-salaries/) | Hard | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0185-department-top-three-salaries/) | [Explanation](leetcode/0185-department-top-three-salaries/Explanation.md) |
| 187 | [Repeated DNA Sequences](leetcode/0187-repeated-dna-sequences/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0187-repeated-dna-sequences/) | [Explanation](leetcode/0187-repeated-dna-sequences/Explanation.md) |
| 188 | [Best Time to Buy and Sell Stock IV](leetcode/0188-best-time-to-buy-and-sell-stock-iv/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0188-best-time-to-buy-and-sell-stock-iv/) | [Explanation](leetcode/0188-best-time-to-buy-and-sell-stock-iv/Explanation.md) |
| 189 | [Rotate Array](leetcode/0189-rotate-array/) | Medium | [Math & Logic](patterns/math-logic.md) | JavaScript | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0189-rotate-array/) | [Explanation](leetcode/0189-rotate-array/Explanation.md) |
| 190 | [Reverse Bits](leetcode/0190-reverse-bits/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0190-reverse-bits/) | [Explanation](leetcode/0190-reverse-bits/Explanation.md) |
| 191 | [Number of 1 Bits](leetcode/0191-number-of-1-bits/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | JavaScript, Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0191-number-of-1-bits/) | [Explanation](leetcode/0191-number-of-1-bits/Explanation.md) |
| 192 | [Word Frequency](leetcode/0192-word-frequency/) | Medium | [Hash Map](patterns/hash-map.md) | Shell | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0192-word-frequency/) | [Explanation](leetcode/0192-word-frequency/Explanation.md) |
| 193 | [Valid Phone Numbers](leetcode/0193-valid-phone-numbers/) | Easy | [Array / General](patterns/array-general.md) | Shell | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0193-valid-phone-numbers/) | [Explanation](leetcode/0193-valid-phone-numbers/Explanation.md) |
| 194 | [Transpose File](leetcode/0194-transpose-file/) | Medium | [Array / General](patterns/array-general.md) | Shell | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0194-transpose-file/) | [Explanation](leetcode/0194-transpose-file/Explanation.md) |
| 195 | [Tenth Line](leetcode/0195-tenth-line/) | Easy | [Array / General](patterns/array-general.md) | Shell | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0195-tenth-line/) | [Explanation](leetcode/0195-tenth-line/Explanation.md) |
| 196 | [Delete Duplicate Emails](leetcode/0196-delete-duplicate-emails/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0196-delete-duplicate-emails/) | [Explanation](leetcode/0196-delete-duplicate-emails/Explanation.md) |
| 197 | [Rising Temperature](leetcode/0197-rising-temperature/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0197-rising-temperature/) | [Explanation](leetcode/0197-rising-temperature/Explanation.md) |
| 198 | [House Robber](leetcode/0198-house-robber/) | Medium | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0198-house-robber/) | [Explanation](leetcode/0198-house-robber/Explanation.md) |
| 199 | [Binary Tree Right Side View](leetcode/0199-binary-tree-right-side-view/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0199-binary-tree-right-side-view/) | [Explanation](leetcode/0199-binary-tree-right-side-view/Explanation.md) |
| 200 | [Number of Islands](leetcode/0200-number-of-islands/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0200-number-of-islands/) | [Explanation](leetcode/0200-number-of-islands/Explanation.md) |
| 201 | [Bitwise AND of Numbers Range](leetcode/0201-bitwise-and-of-numbers-range/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | JavaScript | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0201-bitwise-and-of-numbers-range/) | [Explanation](leetcode/0201-bitwise-and-of-numbers-range/Explanation.md) |
| 202 | [Happy Number](leetcode/0202-happy-number/) | Easy | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0202-happy-number/) | [Explanation](leetcode/0202-happy-number/Explanation.md) |
| 203 | [Remove Linked List Elements](leetcode/0203-remove-linked-list-elements/) | Easy | [Two Pointers](patterns/two-pointers.md) | PHP | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0203-remove-linked-list-elements/) | [Explanation](leetcode/0203-remove-linked-list-elements/Explanation.md) |
| 204 | [Count Primes](leetcode/0204-count-primes/) | Medium | [Tree & Graph](patterns/tree-graph.md) | JavaScript, Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0204-count-primes/) | [Explanation](leetcode/0204-count-primes/Explanation.md) |
| 205 | [Isomorphic Strings](leetcode/0205-isomorphic-strings/) | Easy | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0205-isomorphic-strings/) | [Explanation](leetcode/0205-isomorphic-strings/Explanation.md) |
| 206 | [Reverse Linked List](leetcode/0206-reverse-linked-list/) | Easy | [Two Pointers](patterns/two-pointers.md) | JavaScript, PHP, Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0206-reverse-linked-list/) | [Explanation](leetcode/0206-reverse-linked-list/Explanation.md) |
| 207 | [Course Schedule](leetcode/0207-course-schedule/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0207-course-schedule/) | [Explanation](leetcode/0207-course-schedule/Explanation.md) |
| 208 | [Implement Trie (Prefix Tree)](leetcode/0208-implement-trie-prefix-tree/) | Medium | [Trie](patterns/trie.md) | JavaScript | Prefix Tree Lookup | O(n) | O(n) | [Code](leetcode/0208-implement-trie-prefix-tree/) | [Explanation](leetcode/0208-implement-trie-prefix-tree/Explanation.md) |
| 209 | [Minimum Size Subarray Sum](leetcode/0209-minimum-size-subarray-sum/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0209-minimum-size-subarray-sum/) | [Explanation](leetcode/0209-minimum-size-subarray-sum/Explanation.md) |
| 210 | [Course Schedule II](leetcode/0210-course-schedule-ii/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0210-course-schedule-ii/) | [Explanation](leetcode/0210-course-schedule-ii/Explanation.md) |
| 211 | [Design Add and Search Words Data Structure](leetcode/0211-design-add-and-search-words-data-structure/) | Medium | [Hash Map](patterns/hash-map.md) | JavaScript | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0211-design-add-and-search-words-data-structure/) | [Explanation](leetcode/0211-design-add-and-search-words-data-structure/Explanation.md) |
| 212 | [Word Search II](leetcode/0212-word-search-ii/) | Hard | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0212-word-search-ii/) | [Explanation](leetcode/0212-word-search-ii/Explanation.md) |
| 214 | [Shortest Palindrome](leetcode/0214-shortest-palindrome/) | Hard | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0214-shortest-palindrome/) | [Explanation](leetcode/0214-shortest-palindrome/Explanation.md) |
| 215 | [Kth Largest Element in an Array](leetcode/0215-kth-largest-element-in-an-array/) | Medium | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0215-kth-largest-element-in-an-array/) | [Explanation](leetcode/0215-kth-largest-element-in-an-array/Explanation.md) |
| 216 | [Combination Sum III](leetcode/0216-combination-sum-iii/) | Medium | [Backtracking](patterns/backtracking.md) | JavaScript | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/0216-combination-sum-iii/) | [Explanation](leetcode/0216-combination-sum-iii/Explanation.md) |
| 217 | [Contains Duplicate](leetcode/0217-contains-duplicate/) | Easy | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0217-contains-duplicate/) | [Explanation](leetcode/0217-contains-duplicate/Explanation.md) |
| 218 | [The Skyline Problem](leetcode/0218-the-skyline-problem/) | Hard | [Dynamic Programming](patterns/dynamic-programming.md) | JavaScript | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/0218-the-skyline-problem/) | [Explanation](leetcode/0218-the-skyline-problem/Explanation.md) |
| 219 | [Contains Duplicate II](leetcode/0219-contains-duplicate-ii/) | Easy | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0219-contains-duplicate-ii/) | [Explanation](leetcode/0219-contains-duplicate-ii/Explanation.md) |
| 220 | [Contains Duplicate III](leetcode/0220-contains-duplicate-iii/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0220-contains-duplicate-iii/) | [Explanation](leetcode/0220-contains-duplicate-iii/Explanation.md) |
| 221 | [Maximal Square](leetcode/0221-maximal-square/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0221-maximal-square/) | [Explanation](leetcode/0221-maximal-square/Explanation.md) |
| 222 | [Count Complete Tree Nodes](leetcode/0222-count-complete-tree-nodes/) | Medium | [Two Pointers](patterns/two-pointers.md) | JavaScript | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0222-count-complete-tree-nodes/) | [Explanation](leetcode/0222-count-complete-tree-nodes/Explanation.md) |
| 223 | [Rectangle Area](leetcode/0223-rectangle-area/) | Medium | [Math & Logic](patterns/math-logic.md) | Python | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0223-rectangle-area/) | [Explanation](leetcode/0223-rectangle-area/Explanation.md) |
| 224 | [Basic Calculator](leetcode/0224-basic-calculator/) | Hard | [Bit Manipulation](patterns/bit-manipulation.md) | JavaScript | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0224-basic-calculator/) | [Explanation](leetcode/0224-basic-calculator/Explanation.md) |
| 225 | [Implement Stack using Queues](leetcode/0225-implement-stack-using-queues/) | Easy | [Trie](patterns/trie.md) | PHP | Prefix Tree Lookup | O(n) | O(n) | [Code](leetcode/0225-implement-stack-using-queues/) | [Explanation](leetcode/0225-implement-stack-using-queues/Explanation.md) |
| 226 | [Invert Binary Tree](leetcode/0226-invert-binary-tree/) | Easy | [Binary Search](patterns/binary-search.md) | PHP | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0226-invert-binary-tree/) | [Explanation](leetcode/0226-invert-binary-tree/Explanation.md) |
| 228 | [Summary Ranges](leetcode/0228-summary-ranges/) | Easy | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0228-summary-ranges/) | [Explanation](leetcode/0228-summary-ranges/Explanation.md) |
| 230 | [Kth Smallest Element in a BST](leetcode/0230-kth-smallest-element-in-a-bst/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0230-kth-smallest-element-in-a-bst/) | [Explanation](leetcode/0230-kth-smallest-element-in-a-bst/Explanation.md) |
| 231 | [Power of Two](leetcode/0231-power-of-two/) | Easy | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0231-power-of-two/) | [Explanation](leetcode/0231-power-of-two/Explanation.md) |
| 232 | [Implement Queue using Stacks](leetcode/0232-implement-queue-using-stacks/) | Easy | [Trie](patterns/trie.md) | JavaScript, PHP | Prefix Tree Lookup | O(n) | O(n) | [Code](leetcode/0232-implement-queue-using-stacks/) | [Explanation](leetcode/0232-implement-queue-using-stacks/Explanation.md) |
| 233 | [Number of Digit One](leetcode/0233-number-of-digit-one/) | Hard | [Math & Logic](patterns/math-logic.md) | Python | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0233-number-of-digit-one/) | [Explanation](leetcode/0233-number-of-digit-one/Explanation.md) |
| 234 | [Palindrome Linked List](leetcode/0234-palindrome-linked-list/) | Easy | [Two Pointers](patterns/two-pointers.md) | PHP | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0234-palindrome-linked-list/) | [Explanation](leetcode/0234-palindrome-linked-list/Explanation.md) |
| 235 | [Lowest Common Ancestor of a Binary Search Tree](leetcode/0235-lowest-common-ancestor-of-a-binary-search-tree/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0235-lowest-common-ancestor-of-a-binary-search-tree/) | [Explanation](leetcode/0235-lowest-common-ancestor-of-a-binary-search-tree/Explanation.md) |
| 236 | [Lowest Common Ancestor of a Binary Tree](leetcode/0236-lowest-common-ancestor-of-a-binary-tree/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0236-lowest-common-ancestor-of-a-binary-tree/) | [Explanation](leetcode/0236-lowest-common-ancestor-of-a-binary-tree/Explanation.md) |
| 238 | [Product of Array Except Self](leetcode/0238-product-of-array-except-self/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | JavaScript | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0238-product-of-array-except-self/) | [Explanation](leetcode/0238-product-of-array-except-self/Explanation.md) |
| 239 | [Sliding Window Maximum](leetcode/0239-sliding-window-maximum/) | Hard | [Sliding Window](patterns/sliding-window.md) | Python | Dynamic Sliding Window Traversal | O(n) | O(1) | [Code](leetcode/0239-sliding-window-maximum/) | [Explanation](leetcode/0239-sliding-window-maximum/Explanation.md) |
| 240 | [Search a 2D Matrix II](leetcode/0240-search-a-2d-matrix-ii/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0240-search-a-2d-matrix-ii/) | [Explanation](leetcode/0240-search-a-2d-matrix-ii/Explanation.md) |
| 242 | [Valid Anagram](leetcode/0242-valid-anagram/) | Easy | [Hash Map](patterns/hash-map.md) | PHP | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0242-valid-anagram/) | [Explanation](leetcode/0242-valid-anagram/Explanation.md) |
| 257 | [Binary Tree Paths](leetcode/0257-binary-tree-paths/) | Easy | [Binary Search](patterns/binary-search.md) | PHP | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0257-binary-tree-paths/) | [Explanation](leetcode/0257-binary-tree-paths/Explanation.md) |
| 258 | [Add Digits](leetcode/0258-add-digits/) | Easy | [Math & Logic](patterns/math-logic.md) | PHP | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0258-add-digits/) | [Explanation](leetcode/0258-add-digits/Explanation.md) |
| 262 | [Trips and Users](leetcode/0262-trips-and-users/) | Hard | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0262-trips-and-users/) | [Explanation](leetcode/0262-trips-and-users/Explanation.md) |
| 263 | [Ugly Number](leetcode/0263-ugly-number/) | Easy | [Array / General](patterns/array-general.md) | PHP, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0263-ugly-number/) | [Explanation](leetcode/0263-ugly-number/Explanation.md) |
| 268 | [Missing Number](leetcode/0268-missing-number/) | Easy | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0268-missing-number/) | [Explanation](leetcode/0268-missing-number/Explanation.md) |
| 273 | [Integer to English Words](leetcode/0273-integer-to-english-words/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0273-integer-to-english-words/) | [Explanation](leetcode/0273-integer-to-english-words/Explanation.md) |
| 274 | [H-Index](leetcode/0274-h-index/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0274-h-index/) | [Explanation](leetcode/0274-h-index/Explanation.md) |
| 275 | [H-Index II](leetcode/0275-h-index-ii/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0275-h-index-ii/) | [Explanation](leetcode/0275-h-index-ii/Explanation.md) |
| 278 | [First Bad Version](leetcode/0278-first-bad-version/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0278-first-bad-version/) | [Explanation](leetcode/0278-first-bad-version/Explanation.md) |
| 279 | [Perfect Squares](leetcode/0279-perfect-squares/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0279-perfect-squares/) | [Explanation](leetcode/0279-perfect-squares/Explanation.md) |
| 282 | [Expression Add Operators](leetcode/0282-expression-add-operators/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0282-expression-add-operators/) | [Explanation](leetcode/0282-expression-add-operators/Explanation.md) |
| 283 | [Move Zeroes](leetcode/0283-move-zeroes/) | Easy | [Array / General](patterns/array-general.md) | C++, JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0283-move-zeroes/) | [Explanation](leetcode/0283-move-zeroes/Explanation.md) |
| 287 | [Find the Duplicate Number](leetcode/0287-find-the-duplicate-number/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0287-find-the-duplicate-number/) | [Explanation](leetcode/0287-find-the-duplicate-number/Explanation.md) |
| 289 | [Game of Life](leetcode/0289-game-of-life/) | Medium | [Math & Logic](patterns/math-logic.md) | JavaScript | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0289-game-of-life/) | [Explanation](leetcode/0289-game-of-life/Explanation.md) |
| 290 | [Word Pattern](leetcode/0290-word-pattern/) | Easy | [Hash Map](patterns/hash-map.md) | C++ | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0290-word-pattern/) | [Explanation](leetcode/0290-word-pattern/Explanation.md) |
| 292 | [Nim Game](leetcode/0292-nim-game/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0292-nim-game/) | [Explanation](leetcode/0292-nim-game/Explanation.md) |
| 295 | [Find Median from Data Stream](leetcode/0295-find-median-from-data-stream/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0295-find-median-from-data-stream/) | [Explanation](leetcode/0295-find-median-from-data-stream/Explanation.md) |
| 297 | [Serialize and Deserialize Binary Tree](leetcode/0297-serialize-and-deserialize-binary-tree/) | Hard | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0297-serialize-and-deserialize-binary-tree/) | [Explanation](leetcode/0297-serialize-and-deserialize-binary-tree/Explanation.md) |
| 300 | [Longest Increasing Subsequence](leetcode/0300-longest-increasing-subsequence/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0300-longest-increasing-subsequence/) | [Explanation](leetcode/0300-longest-increasing-subsequence/Explanation.md) |
| 301 | [Remove Invalid Parentheses](leetcode/0301-remove-invalid-parentheses/) | Hard | [Stack & Queue](patterns/stack-queue.md) | Python | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/0301-remove-invalid-parentheses/) | [Explanation](leetcode/0301-remove-invalid-parentheses/Explanation.md) |
| 303 | [Range Sum Query   Immutable](leetcode/0303-range-sum-query---immutable/) | Medium | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0303-range-sum-query---immutable/) | [Explanation](leetcode/0303-range-sum-query---immutable/Explanation.md) |
| 307 | [Range Sum Query   Mutable](leetcode/0307-range-sum-query---mutable/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0307-range-sum-query---mutable/) | [Explanation](leetcode/0307-range-sum-query---mutable/Explanation.md) |
| 312 | [Burst Balloons](leetcode/0312-burst-balloons/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0312-burst-balloons/) | [Explanation](leetcode/0312-burst-balloons/Explanation.md) |
| 315 | [Count of Smaller Numbers After Self](leetcode/0315-count-of-smaller-numbers-after-self/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0315-count-of-smaller-numbers-after-self/) | [Explanation](leetcode/0315-count-of-smaller-numbers-after-self/Explanation.md) |
| 319 | [Bulb Switcher](leetcode/0319-bulb-switcher/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0319-bulb-switcher/) | [Explanation](leetcode/0319-bulb-switcher/Explanation.md) |
| 321 | [Create Maximum Number](leetcode/0321-create-maximum-number/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0321-create-maximum-number/) | [Explanation](leetcode/0321-create-maximum-number/Explanation.md) |
| 322 | [Coin Change](leetcode/0322-coin-change/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0322-coin-change/) | [Explanation](leetcode/0322-coin-change/Explanation.md) |
| 326 | [Power of Three](leetcode/0326-power-of-three/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0326-power-of-three/) | [Explanation](leetcode/0326-power-of-three/Explanation.md) |
| 327 | [Count of Range Sum](leetcode/0327-count-of-range-sum/) | Hard | [Bit Manipulation](patterns/bit-manipulation.md) | JavaScript | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0327-count-of-range-sum/) | [Explanation](leetcode/0327-count-of-range-sum/Explanation.md) |
| 328 | [Odd Even Linked List](leetcode/0328-odd-even-linked-list/) | Medium | [Two Pointers](patterns/two-pointers.md) | JavaScript, Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0328-odd-even-linked-list/) | [Explanation](leetcode/0328-odd-even-linked-list/Explanation.md) |
| 329 | [Longest Increasing Path in a Matrix](leetcode/0329-longest-increasing-path-in-a-matrix/) | Hard | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0329-longest-increasing-path-in-a-matrix/) | [Explanation](leetcode/0329-longest-increasing-path-in-a-matrix/Explanation.md) |
| 330 | [Patching Array](leetcode/0330-patching-array/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0330-patching-array/) | [Explanation](leetcode/0330-patching-array/Explanation.md) |
| 332 | [Reconstruct Itinerary](leetcode/0332-reconstruct-itinerary/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0332-reconstruct-itinerary/) | [Explanation](leetcode/0332-reconstruct-itinerary/Explanation.md) |
| 334 | [Increasing Triplet Subsequence](leetcode/0334-increasing-triplet-subsequence/) | Medium | [Dynamic Programming](patterns/dynamic-programming.md) | JavaScript | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/0334-increasing-triplet-subsequence/) | [Explanation](leetcode/0334-increasing-triplet-subsequence/Explanation.md) |
| 335 | [Self Crossing](leetcode/0335-self-crossing/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0335-self-crossing/) | [Explanation](leetcode/0335-self-crossing/Explanation.md) |
| 336 | [Palindrome Pairs](leetcode/0336-palindrome-pairs/) | Hard | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0336-palindrome-pairs/) | [Explanation](leetcode/0336-palindrome-pairs/Explanation.md) |
| 338 | [Counting Bits](leetcode/0338-counting-bits/) | Easy | [Binary Search](patterns/binary-search.md) | C++, JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0338-counting-bits/) | [Explanation](leetcode/0338-counting-bits/Explanation.md) |
| 342 | [Power of Four](leetcode/0342-power-of-four/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0342-power-of-four/) | [Explanation](leetcode/0342-power-of-four/Explanation.md) |
| 344 | [Reverse String](leetcode/0344-reverse-string/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0344-reverse-string/) | [Explanation](leetcode/0344-reverse-string/Explanation.md) |
| 345 | [Reverse Vowels of a String](leetcode/0345-reverse-vowels-of-a-string/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0345-reverse-vowels-of-a-string/) | [Explanation](leetcode/0345-reverse-vowels-of-a-string/Explanation.md) |
| 347 | [Top K Frequent Elements](leetcode/0347-top-k-frequent-elements/) | Medium | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n log n) | O(1) | [Code](leetcode/0347-top-k-frequent-elements/) | [Explanation](leetcode/0347-top-k-frequent-elements/Explanation.md) |
| 349 | [Intersection of Two Arrays](leetcode/0349-intersection-of-two-arrays/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0349-intersection-of-two-arrays/) | [Explanation](leetcode/0349-intersection-of-two-arrays/Explanation.md) |
| 350 | [Intersection of Two Arrays II](leetcode/0350-intersection-of-two-arrays-ii/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0350-intersection-of-two-arrays-ii/) | [Explanation](leetcode/0350-intersection-of-two-arrays-ii/Explanation.md) |
| 352 | [Data Stream as Disjoint Intervals](leetcode/0352-data-stream-as-disjoint-intervals/) | Hard | [Heap](patterns/heap.md) | Python | Min/Max Heap Priority Selection | O(n) | O(n) | [Code](leetcode/0352-data-stream-as-disjoint-intervals/) | [Explanation](leetcode/0352-data-stream-as-disjoint-intervals/Explanation.md) |
| 354 | [Russian Doll Envelopes](leetcode/0354-russian-doll-envelopes/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0354-russian-doll-envelopes/) | [Explanation](leetcode/0354-russian-doll-envelopes/Explanation.md) |
| 363 | [Max Sum of Rectangle No Larger Than K](leetcode/0363-max-sum-of-rectangle-no-larger-than-k/) | Hard | [Math & Logic](patterns/math-logic.md) | Python | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0363-max-sum-of-rectangle-no-larger-than-k/) | [Explanation](leetcode/0363-max-sum-of-rectangle-no-larger-than-k/Explanation.md) |
| 365 | [Water and Jug Problem](leetcode/0365-water-and-jug-problem/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0365-water-and-jug-problem/) | [Explanation](leetcode/0365-water-and-jug-problem/Explanation.md) |
| 367 | [Valid Perfect Square](leetcode/0367-valid-perfect-square/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0367-valid-perfect-square/) | [Explanation](leetcode/0367-valid-perfect-square/Explanation.md) |
| 371 | [Sum of Two Integers](leetcode/0371-sum-of-two-integers/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0371-sum-of-two-integers/) | [Explanation](leetcode/0371-sum-of-two-integers/Explanation.md) |
| 373 | [Find K Pairs with Smallest Sums](leetcode/0373-find-k-pairs-with-smallest-sums/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0373-find-k-pairs-with-smallest-sums/) | [Explanation](leetcode/0373-find-k-pairs-with-smallest-sums/Explanation.md) |
| 374 | [Guess Number Higher or Lower](leetcode/0374-guess-number-higher-or-lower/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0374-guess-number-higher-or-lower/) | [Explanation](leetcode/0374-guess-number-higher-or-lower/Explanation.md) |
| 375 | [Guess Number Higher or Lower II](leetcode/0375-guess-number-higher-or-lower-ii/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0375-guess-number-higher-or-lower-ii/) | [Explanation](leetcode/0375-guess-number-higher-or-lower-ii/Explanation.md) |
| 380 | [Insert Delete GetRandom O(1)](leetcode/0380-insert-delete-getrandom-o1/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0380-insert-delete-getrandom-o1/) | [Explanation](leetcode/0380-insert-delete-getrandom-o1/Explanation.md) |
| 381 | [Insert Delete Getrandom O1   Duplicates Allowed](leetcode/0381-insert-delete-getrandom-o1---duplicates-allowed/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0381-insert-delete-getrandom-o1---duplicates-allowed/) | [Explanation](leetcode/0381-insert-delete-getrandom-o1---duplicates-allowed/Explanation.md) |
| 383 | [Ransom Note](leetcode/0383-ransom-note/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0383-ransom-note/) | [Explanation](leetcode/0383-ransom-note/Explanation.md) |
| 387 | [First Unique Character in a String](leetcode/0387-first-unique-character-in-a-string/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0387-first-unique-character-in-a-string/) | [Explanation](leetcode/0387-first-unique-character-in-a-string/Explanation.md) |
| 389 | [Find the Difference](leetcode/0389-find-the-difference/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0389-find-the-difference/) | [Explanation](leetcode/0389-find-the-difference/Explanation.md) |
| 391 | [Perfect Rectangle](leetcode/0391-perfect-rectangle/) | Hard | [Math & Logic](patterns/math-logic.md) | Python | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0391-perfect-rectangle/) | [Explanation](leetcode/0391-perfect-rectangle/Explanation.md) |
| 392 | [Is Subsequence](leetcode/0392-is-subsequence/) | Easy | [Dynamic Programming](patterns/dynamic-programming.md) | JavaScript, Python | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/0392-is-subsequence/) | [Explanation](leetcode/0392-is-subsequence/Explanation.md) |
| 394 | [Decode String](leetcode/0394-decode-string/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0394-decode-string/) | [Explanation](leetcode/0394-decode-string/Explanation.md) |
| 396 | [Rotate Function](leetcode/0396-rotate-function/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | C++ | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0396-rotate-function/) | [Explanation](leetcode/0396-rotate-function/Explanation.md) |
| 399 | [Evaluate Division](leetcode/0399-evaluate-division/) | Medium | [Stack & Queue](patterns/stack-queue.md) | JavaScript | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/0399-evaluate-division/) | [Explanation](leetcode/0399-evaluate-division/Explanation.md) |
| 401 | [Binary Watch](leetcode/0401-binary-watch/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0401-binary-watch/) | [Explanation](leetcode/0401-binary-watch/Explanation.md) |
| 403 | [Frog Jump](leetcode/0403-frog-jump/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0403-frog-jump/) | [Explanation](leetcode/0403-frog-jump/Explanation.md) |
| 404 | [Sum of Left Leaves](leetcode/0404-sum-of-left-leaves/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0404-sum-of-left-leaves/) | [Explanation](leetcode/0404-sum-of-left-leaves/Explanation.md) |
| 405 | [Convert a Number to Hexadecimal](leetcode/0405-convert-a-number-to-hexadecimal/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0405-convert-a-number-to-hexadecimal/) | [Explanation](leetcode/0405-convert-a-number-to-hexadecimal/Explanation.md) |
| 406 | [Queue Reconstruction by Height](leetcode/0406-queue-reconstruction-by-height/) | Medium | [Stack & Queue](patterns/stack-queue.md) | JavaScript | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/0406-queue-reconstruction-by-height/) | [Explanation](leetcode/0406-queue-reconstruction-by-height/Explanation.md) |
| 407 | [Trapping Rain Water II](leetcode/0407-trapping-rain-water-ii/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0407-trapping-rain-water-ii/) | [Explanation](leetcode/0407-trapping-rain-water-ii/Explanation.md) |
| 409 | [Longest Palindrome](leetcode/0409-longest-palindrome/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0409-longest-palindrome/) | [Explanation](leetcode/0409-longest-palindrome/Explanation.md) |
| 410 | [Split Array Largest Sum](leetcode/0410-split-array-largest-sum/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0410-split-array-largest-sum/) | [Explanation](leetcode/0410-split-array-largest-sum/Explanation.md) |
| 412 | [Fizz Buzz](leetcode/0412-fizz-buzz/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0412-fizz-buzz/) | [Explanation](leetcode/0412-fizz-buzz/Explanation.md) |
| 414 | [Third Maximum Number](leetcode/0414-third-maximum-number/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0414-third-maximum-number/) | [Explanation](leetcode/0414-third-maximum-number/Explanation.md) |
| 415 | [Add Strings](leetcode/0415-add-strings/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0415-add-strings/) | [Explanation](leetcode/0415-add-strings/Explanation.md) |
| 420 | [Strong Password Checker](leetcode/0420-strong-password-checker/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0420-strong-password-checker/) | [Explanation](leetcode/0420-strong-password-checker/Explanation.md) |
| 427 | [Construct Quad Tree](leetcode/0772-construct-quad-tree/) | Medium | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0772-construct-quad-tree/) | [Explanation](leetcode/0772-construct-quad-tree/Explanation.md) |
| 432 | [All O`one Data Structure](leetcode/0432-all-oone-data-structure/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0432-all-oone-data-structure/) | [Explanation](leetcode/0432-all-oone-data-structure/Explanation.md) |
| 433 | [Minimum Genetic Mutation](leetcode/0433-minimum-genetic-mutation/) | Medium | [Sliding Window](patterns/sliding-window.md) | JavaScript | Dynamic Sliding Window Traversal | O(n) | O(1) | [Code](leetcode/0433-minimum-genetic-mutation/) | [Explanation](leetcode/0433-minimum-genetic-mutation/Explanation.md) |
| 434 | [Number of Segments in a String](leetcode/0434-number-of-segments-in-a-string/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0434-number-of-segments-in-a-string/) | [Explanation](leetcode/0434-number-of-segments-in-a-string/Explanation.md) |
| 435 | [Non-overlapping Intervals](leetcode/0435-non-overlapping-intervals/) | Medium | [Heap](patterns/heap.md) | JavaScript | Min/Max Heap Priority Selection | O(n) | O(n) | [Code](leetcode/0435-non-overlapping-intervals/) | [Explanation](leetcode/0435-non-overlapping-intervals/Explanation.md) |
| 436 | [Find Right Interval](leetcode/0436-find-right-interval/) | Medium | [Heap](patterns/heap.md) | JavaScript | Min/Max Heap Priority Selection | O(n) | O(n) | [Code](leetcode/0436-find-right-interval/) | [Explanation](leetcode/0436-find-right-interval/Explanation.md) |
| 437 | [Path Sum III](leetcode/0437-path-sum-iii/) | Medium | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0437-path-sum-iii/) | [Explanation](leetcode/0437-path-sum-iii/Explanation.md) |
| 438 | [Find All Anagrams in a String](leetcode/0438-find-all-anagrams-in-a-string/) | Medium | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0438-find-all-anagrams-in-a-string/) | [Explanation](leetcode/0438-find-all-anagrams-in-a-string/Explanation.md) |
| 440 | [K-th Smallest in Lexicographical Order](leetcode/0440-k-th-smallest-in-lexicographical-order/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0440-k-th-smallest-in-lexicographical-order/) | [Explanation](leetcode/0440-k-th-smallest-in-lexicographical-order/Explanation.md) |
| 441 | [Arranging Coins](leetcode/0441-arranging-coins/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0441-arranging-coins/) | [Explanation](leetcode/0441-arranging-coins/Explanation.md) |
| 443 | [String Compression](leetcode/0443-string-compression/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0443-string-compression/) | [Explanation](leetcode/0443-string-compression/Explanation.md) |
| 446 | [Arithmetic Slices Ii   Subsequence](leetcode/0446-arithmetic-slices-ii---subsequence/) | Medium | [Dynamic Programming](patterns/dynamic-programming.md) | Python | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/0446-arithmetic-slices-ii---subsequence/) | [Explanation](leetcode/0446-arithmetic-slices-ii---subsequence/Explanation.md) |
| 448 | [Find All Numbers Disappeared in an Array](leetcode/0448-find-all-numbers-disappeared-in-an-array/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0448-find-all-numbers-disappeared-in-an-array/) | [Explanation](leetcode/0448-find-all-numbers-disappeared-in-an-array/Explanation.md) |
| 450 | [Delete Node in a BST](leetcode/0450-delete-node-in-a-bst/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0450-delete-node-in-a-bst/) | [Explanation](leetcode/0450-delete-node-in-a-bst/Explanation.md) |
| 452 | [Minimum Number of Arrows to Burst Balloons](leetcode/0452-minimum-number-of-arrows-to-burst-balloons/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0452-minimum-number-of-arrows-to-burst-balloons/) | [Explanation](leetcode/0452-minimum-number-of-arrows-to-burst-balloons/Explanation.md) |
| 455 | [Assign Cookies](leetcode/0455-assign-cookies/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0455-assign-cookies/) | [Explanation](leetcode/0455-assign-cookies/Explanation.md) |
| 458 | [Poor Pigs](leetcode/0458-poor-pigs/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0458-poor-pigs/) | [Explanation](leetcode/0458-poor-pigs/Explanation.md) |
| 459 | [Repeated Substring Pattern](leetcode/0459-repeated-substring-pattern/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0459-repeated-substring-pattern/) | [Explanation](leetcode/0459-repeated-substring-pattern/Explanation.md) |
| 460 | [LFU Cache](leetcode/0460-lfu-cache/) | Hard | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0460-lfu-cache/) | [Explanation](leetcode/0460-lfu-cache/Explanation.md) |
| 461 | [Hamming Distance](leetcode/0461-hamming-distance/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0461-hamming-distance/) | [Explanation](leetcode/0461-hamming-distance/Explanation.md) |
| 463 | [Island Perimeter](leetcode/0463-island-perimeter/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0463-island-perimeter/) | [Explanation](leetcode/0463-island-perimeter/Explanation.md) |
| 464 | [Can I Win](leetcode/0464-can-i-win/) | Medium | [Monotonic Stack](patterns/monotonic-stack.md) | Python | Monotonic Stack Filtering | O(n) | O(n) | [Code](leetcode/0464-can-i-win/) | [Explanation](leetcode/0464-can-i-win/Explanation.md) |
| 466 | [Count The Repetitions](leetcode/0466-count-the-repetitions/) | Hard | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0466-count-the-repetitions/) | [Explanation](leetcode/0466-count-the-repetitions/Explanation.md) |
| 472 | [Concatenated Words](leetcode/0472-concatenated-words/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0472-concatenated-words/) | [Explanation](leetcode/0472-concatenated-words/Explanation.md) |
| 476 | [Number Complement](leetcode/0476-number-complement/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0476-number-complement/) | [Explanation](leetcode/0476-number-complement/Explanation.md) |
| 479 | [Largest Palindrome Product](leetcode/0479-largest-palindrome-product/) | Hard | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0479-largest-palindrome-product/) | [Explanation](leetcode/0479-largest-palindrome-product/Explanation.md) |
| 480 | [Sliding Window Median](leetcode/0480-sliding-window-median/) | Hard | [Sliding Window](patterns/sliding-window.md) | Python | Dynamic Sliding Window Traversal | O(n) | O(1) | [Code](leetcode/0480-sliding-window-median/) | [Explanation](leetcode/0480-sliding-window-median/Explanation.md) |
| 482 | [License Key Formatting](leetcode/0482-license-key-formatting/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0482-license-key-formatting/) | [Explanation](leetcode/0482-license-key-formatting/Explanation.md) |
| 483 | [Smallest Good Base](leetcode/0483-smallest-good-base/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0483-smallest-good-base/) | [Explanation](leetcode/0483-smallest-good-base/Explanation.md) |
| 485 | [Max Consecutive Ones](leetcode/0485-max-consecutive-ones/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0485-max-consecutive-ones/) | [Explanation](leetcode/0485-max-consecutive-ones/Explanation.md) |
| 486 | [Predict the Winner](leetcode/0486-predict-the-winner/) | Medium | [Dynamic Programming](patterns/dynamic-programming.md) | C++ | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/0486-predict-the-winner/) | [Explanation](leetcode/0486-predict-the-winner/Explanation.md) |
| 492 | [Construct the Rectangle](leetcode/0492-construct-the-rectangle/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0492-construct-the-rectangle/) | [Explanation](leetcode/0492-construct-the-rectangle/Explanation.md) |
| 493 | [Reverse Pairs](leetcode/0493-reverse-pairs/) | Hard | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0493-reverse-pairs/) | [Explanation](leetcode/0493-reverse-pairs/Explanation.md) |
| 495 | [Teemo Attacking](leetcode/0495-teemo-attacking/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0495-teemo-attacking/) | [Explanation](leetcode/0495-teemo-attacking/Explanation.md) |
| 496 | [Next Greater Element I](leetcode/0496-next-greater-element-i/) | Easy | [Monotonic Stack](patterns/monotonic-stack.md) | Python | Monotonic Stack Filtering | O(n) | O(n) | [Code](leetcode/0496-next-greater-element-i/) | [Explanation](leetcode/0496-next-greater-element-i/Explanation.md) |
| 500 | [Keyboard Row](leetcode/0500-keyboard-row/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0500-keyboard-row/) | [Explanation](leetcode/0500-keyboard-row/Explanation.md) |
| 501 | [Find Mode in Binary Search Tree](leetcode/0501-find-mode-in-binary-search-tree/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0501-find-mode-in-binary-search-tree/) | [Explanation](leetcode/0501-find-mode-in-binary-search-tree/Explanation.md) |
| 502 | [IPO](leetcode/0502-ipo/) | Hard | [Bit Manipulation](patterns/bit-manipulation.md) | JavaScript | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0502-ipo/) | [Explanation](leetcode/0502-ipo/Explanation.md) |
| 504 | [Base 7](leetcode/0504-base-7/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0504-base-7/) | [Explanation](leetcode/0504-base-7/Explanation.md) |
| 506 | [Relative Ranks](leetcode/0506-relative-ranks/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0506-relative-ranks/) | [Explanation](leetcode/0506-relative-ranks/Explanation.md) |
| 507 | [Perfect Number](leetcode/0507-perfect-number/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0507-perfect-number/) | [Explanation](leetcode/0507-perfect-number/Explanation.md) |
| 509 | [Fibonacci Number](leetcode/1013-fibonacci-number/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1013-fibonacci-number/) | [Explanation](leetcode/1013-fibonacci-number/Explanation.md) |
| 511 | [Game Play Analysis I](leetcode/1179-game-play-analysis-i/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1179-game-play-analysis-i/) | [Explanation](leetcode/1179-game-play-analysis-i/Explanation.md) |
| 514 | [Freedom Trail](leetcode/0514-freedom-trail/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0514-freedom-trail/) | [Explanation](leetcode/0514-freedom-trail/Explanation.md) |
| 517 | [Super Washing Machines](leetcode/0517-super-washing-machines/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0517-super-washing-machines/) | [Explanation](leetcode/0517-super-washing-machines/Explanation.md) |
| 520 | [Detect Capital](leetcode/0520-detect-capital/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0520-detect-capital/) | [Explanation](leetcode/0520-detect-capital/Explanation.md) |
| 521 | [Longest Uncommon Subsequence I](leetcode/0521-longest-uncommon-subsequence-i/) | Easy | [Dynamic Programming](patterns/dynamic-programming.md) | Python | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/0521-longest-uncommon-subsequence-i/) | [Explanation](leetcode/0521-longest-uncommon-subsequence-i/Explanation.md) |
| 528 | [Random Pick with Weight](leetcode/0912-random-pick-with-weight/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0912-random-pick-with-weight/) | [Explanation](leetcode/0912-random-pick-with-weight/Explanation.md) |
| 530 | [Minimum Absolute Difference in BST](leetcode/0530-minimum-absolute-difference-in-bst/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0530-minimum-absolute-difference-in-bst/) | [Explanation](leetcode/0530-minimum-absolute-difference-in-bst/Explanation.md) |
| 540 | [Single Element in a Sorted Array](leetcode/0540-single-element-in-a-sorted-array/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(log n) | O(1) | [Code](leetcode/0540-single-element-in-a-sorted-array/) | [Explanation](leetcode/0540-single-element-in-a-sorted-array/Explanation.md) |
| 541 | [Reverse String II](leetcode/0541-reverse-string-ii/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0541-reverse-string-ii/) | [Explanation](leetcode/0541-reverse-string-ii/Explanation.md) |
| 543 | [Diameter of Binary Tree](leetcode/0543-diameter-of-binary-tree/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0543-diameter-of-binary-tree/) | [Explanation](leetcode/0543-diameter-of-binary-tree/Explanation.md) |
| 546 | [Remove Boxes](leetcode/0546-remove-boxes/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0546-remove-boxes/) | [Explanation](leetcode/0546-remove-boxes/Explanation.md) |
| 547 | [Number of Provinces](leetcode/0547-number-of-provinces/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0547-number-of-provinces/) | [Explanation](leetcode/0547-number-of-provinces/Explanation.md) |
| 550 | [Game Play Analysis IV](leetcode/1182-game-play-analysis-iv/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1182-game-play-analysis-iv/) | [Explanation](leetcode/1182-game-play-analysis-iv/Explanation.md) |
| 551 | [Student Attendance Record I](leetcode/0551-student-attendance-record-i/) | Easy | [Monotonic Stack](patterns/monotonic-stack.md) | Python | Monotonic Stack Filtering | O(n) | O(n) | [Code](leetcode/0551-student-attendance-record-i/) | [Explanation](leetcode/0551-student-attendance-record-i/Explanation.md) |
| 552 | [Student Attendance Record II](leetcode/0552-student-attendance-record-ii/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0552-student-attendance-record-ii/) | [Explanation](leetcode/0552-student-attendance-record-ii/Explanation.md) |
| 557 | [Reverse Words in a String III](leetcode/0557-reverse-words-in-a-string-iii/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0557-reverse-words-in-a-string-iii/) | [Explanation](leetcode/0557-reverse-words-in-a-string-iii/Explanation.md) |
| 559 | [Maximum Depth of N-ary Tree](leetcode/0774-maximum-depth-of-n-ary-tree/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0774-maximum-depth-of-n-ary-tree/) | [Explanation](leetcode/0774-maximum-depth-of-n-ary-tree/Explanation.md) |
| 560 | [Subarray Sum Equals K](leetcode/0560-subarray-sum-equals-k/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0560-subarray-sum-equals-k/) | [Explanation](leetcode/0560-subarray-sum-equals-k/Explanation.md) |
| 561 | [Array Partition](leetcode/0561-array-partition/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0561-array-partition/) | [Explanation](leetcode/0561-array-partition/Explanation.md) |
| 563 | [Binary Tree Tilt](leetcode/0563-binary-tree-tilt/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0563-binary-tree-tilt/) | [Explanation](leetcode/0563-binary-tree-tilt/Explanation.md) |
| 566 | [Reshape the Matrix](leetcode/0566-reshape-the-matrix/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0566-reshape-the-matrix/) | [Explanation](leetcode/0566-reshape-the-matrix/Explanation.md) |
| 570 | [Managers with at Least 5 Direct Reports](leetcode/0570-managers-with-at-least-5-direct-reports/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0570-managers-with-at-least-5-direct-reports/) | [Explanation](leetcode/0570-managers-with-at-least-5-direct-reports/Explanation.md) |
| 572 | [Subtree of Another Tree](leetcode/0572-subtree-of-another-tree/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0572-subtree-of-another-tree/) | [Explanation](leetcode/0572-subtree-of-another-tree/Explanation.md) |
| 575 | [Distribute Candies](leetcode/0575-distribute-candies/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0575-distribute-candies/) | [Explanation](leetcode/0575-distribute-candies/Explanation.md) |
| 577 | [Employee Bonus](leetcode/0577-employee-bonus/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0577-employee-bonus/) | [Explanation](leetcode/0577-employee-bonus/Explanation.md) |
| 584 | [Find Customer Referee](leetcode/0584-find-customer-referee/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0584-find-customer-referee/) | [Explanation](leetcode/0584-find-customer-referee/Explanation.md) |
| 585 | [Investments in 2016](leetcode/0585-investments-in-2016/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0585-investments-in-2016/) | [Explanation](leetcode/0585-investments-in-2016/Explanation.md) |
| 586 | [Customer Placing the Largest Number of Orders](leetcode/0586-customer-placing-the-largest-number-of-orders/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0586-customer-placing-the-largest-number-of-orders/) | [Explanation](leetcode/0586-customer-placing-the-largest-number-of-orders/Explanation.md) |
| 587 | [Erect the Fence](leetcode/0587-erect-the-fence/) | Hard | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0587-erect-the-fence/) | [Explanation](leetcode/0587-erect-the-fence/Explanation.md) |
| 589 | [N-ary Tree Preorder Traversal](leetcode/0775-n-ary-tree-preorder-traversal/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0775-n-ary-tree-preorder-traversal/) | [Explanation](leetcode/0775-n-ary-tree-preorder-traversal/Explanation.md) |
| 590 | [N-ary Tree Postorder Traversal](leetcode/0776-n-ary-tree-postorder-traversal/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0776-n-ary-tree-postorder-traversal/) | [Explanation](leetcode/0776-n-ary-tree-postorder-traversal/Explanation.md) |
| 591 | [Tag Validator](leetcode/0591-tag-validator/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0591-tag-validator/) | [Explanation](leetcode/0591-tag-validator/Explanation.md) |
| 592 | [Fraction Addition and Subtraction](leetcode/0592-fraction-addition-and-subtraction/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0592-fraction-addition-and-subtraction/) | [Explanation](leetcode/0592-fraction-addition-and-subtraction/Explanation.md) |
| 594 | [Longest Harmonious Subsequence](leetcode/0594-longest-harmonious-subsequence/) | Easy | [Dynamic Programming](patterns/dynamic-programming.md) | Python | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/0594-longest-harmonious-subsequence/) | [Explanation](leetcode/0594-longest-harmonious-subsequence/Explanation.md) |
| 595 | [Big Countries](leetcode/0595-big-countries/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0595-big-countries/) | [Explanation](leetcode/0595-big-countries/Explanation.md) |
| 596 | [Classes With at Least 5 Students](leetcode/0596-classes-with-at-least-5-students/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0596-classes-with-at-least-5-students/) | [Explanation](leetcode/0596-classes-with-at-least-5-students/Explanation.md) |
| 598 | [Range Addition II](leetcode/0598-range-addition-ii/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0598-range-addition-ii/) | [Explanation](leetcode/0598-range-addition-ii/Explanation.md) |
| 599 | [Minimum Index Sum of Two Lists](leetcode/0599-minimum-index-sum-of-two-lists/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0599-minimum-index-sum-of-two-lists/) | [Explanation](leetcode/0599-minimum-index-sum-of-two-lists/Explanation.md) |
| 600 | [Non-negative Integers without Consecutive Ones](leetcode/0600-non-negative-integers-without-consecutive-ones/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0600-non-negative-integers-without-consecutive-ones/) | [Explanation](leetcode/0600-non-negative-integers-without-consecutive-ones/Explanation.md) |
| 601 | [Human Traffic of Stadium](leetcode/0601-human-traffic-of-stadium/) | Hard | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0601-human-traffic-of-stadium/) | [Explanation](leetcode/0601-human-traffic-of-stadium/Explanation.md) |
| 602 | [Friend Requests II: Who Has the Most Friends](leetcode/0602-friend-requests-ii-who-has-the-most-friends/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0602-friend-requests-ii-who-has-the-most-friends/) | [Explanation](leetcode/0602-friend-requests-ii-who-has-the-most-friends/Explanation.md) |
| 605 | [Can Place Flowers](leetcode/0605-can-place-flowers/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0605-can-place-flowers/) | [Explanation](leetcode/0605-can-place-flowers/Explanation.md) |
| 607 | [Sales Person](leetcode/0607-sales-person/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0607-sales-person/) | [Explanation](leetcode/0607-sales-person/Explanation.md) |
| 608 | [Tree Node](leetcode/0608-tree-node/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0608-tree-node/) | [Explanation](leetcode/0608-tree-node/Explanation.md) |
| 610 | [Triangle Judgement](leetcode/0610-triangle-judgement/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0610-triangle-judgement/) | [Explanation](leetcode/0610-triangle-judgement/Explanation.md) |
| 611 | [Valid Triangle Number](leetcode/0611-valid-triangle-number/) | Medium | [Math & Logic](patterns/math-logic.md) | JavaScript | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0611-valid-triangle-number/) | [Explanation](leetcode/0611-valid-triangle-number/Explanation.md) |
| 617 | [Merge Two Binary Trees](leetcode/0617-merge-two-binary-trees/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0617-merge-two-binary-trees/) | [Explanation](leetcode/0617-merge-two-binary-trees/Explanation.md) |
| 619 | [Biggest Single Number](leetcode/0619-biggest-single-number/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0619-biggest-single-number/) | [Explanation](leetcode/0619-biggest-single-number/Explanation.md) |
| 620 | [Not Boring Movies](leetcode/0620-not-boring-movies/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0620-not-boring-movies/) | [Explanation](leetcode/0620-not-boring-movies/Explanation.md) |
| 626 | [Exchange Seats](leetcode/0626-exchange-seats/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0626-exchange-seats/) | [Explanation](leetcode/0626-exchange-seats/Explanation.md) |
| 627 | [Swap Sex of Employees](leetcode/0627-swap-sex-of-employees/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/0627-swap-sex-of-employees/) | [Explanation](leetcode/0627-swap-sex-of-employees/Explanation.md) |
| 628 | [Maximum Product of Three Numbers](leetcode/0628-maximum-product-of-three-numbers/) | Easy | [Binary Search](patterns/binary-search.md) | Elixir | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0628-maximum-product-of-three-numbers/) | [Explanation](leetcode/0628-maximum-product-of-three-numbers/Explanation.md) |
| 629 | [K Inverse Pairs Array](leetcode/0629-k-inverse-pairs-array/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0629-k-inverse-pairs-array/) | [Explanation](leetcode/0629-k-inverse-pairs-array/Explanation.md) |
| 630 | [Course Schedule III](leetcode/0630-course-schedule-iii/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0630-course-schedule-iii/) | [Explanation](leetcode/0630-course-schedule-iii/Explanation.md) |
| 632 | [Smallest Range Covering Elements from K Lists](leetcode/0632-smallest-range-covering-elements-from-k-lists/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0632-smallest-range-covering-elements-from-k-lists/) | [Explanation](leetcode/0632-smallest-range-covering-elements-from-k-lists/Explanation.md) |
| 633 | [Sum of Square Numbers](leetcode/0633-sum-of-square-numbers/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0633-sum-of-square-numbers/) | [Explanation](leetcode/0633-sum-of-square-numbers/Explanation.md) |
| 636 | [Exclusive Time of Functions](leetcode/0636-exclusive-time-of-functions/) | Medium | [Stack & Queue](patterns/stack-queue.md) | TypeScript | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/0636-exclusive-time-of-functions/) | [Explanation](leetcode/0636-exclusive-time-of-functions/Explanation.md) |
| 637 | [Average of Levels in Binary Tree](leetcode/0637-average-of-levels-in-binary-tree/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0637-average-of-levels-in-binary-tree/) | [Explanation](leetcode/0637-average-of-levels-in-binary-tree/Explanation.md) |
| 639 | [Decode Ways II](leetcode/0639-decode-ways-ii/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0639-decode-ways-ii/) | [Explanation](leetcode/0639-decode-ways-ii/Explanation.md) |
| 643 | [Maximum Average Subarray I](leetcode/0643-maximum-average-subarray-i/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0643-maximum-average-subarray-i/) | [Explanation](leetcode/0643-maximum-average-subarray-i/Explanation.md) |
| 645 | [Set Mismatch](leetcode/0645-set-mismatch/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | TypeScript | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0645-set-mismatch/) | [Explanation](leetcode/0645-set-mismatch/Explanation.md) |
| 649 | [Dota2 Senate](leetcode/0649-dota2-senate/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0649-dota2-senate/) | [Explanation](leetcode/0649-dota2-senate/Explanation.md) |
| 653 | [Two Sum Iv   Input Is A Bst](leetcode/0653-two-sum-iv---input-is-a-bst/) | Medium | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0653-two-sum-iv---input-is-a-bst/) | [Explanation](leetcode/0653-two-sum-iv---input-is-a-bst/Explanation.md) |
| 657 | [Robot Return to Origin](leetcode/0657-robot-return-to-origin/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0657-robot-return-to-origin/) | [Explanation](leetcode/0657-robot-return-to-origin/Explanation.md) |
| 658 | [Find K Closest Elements](leetcode/0658-find-k-closest-elements/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0658-find-k-closest-elements/) | [Explanation](leetcode/0658-find-k-closest-elements/Explanation.md) |
| 661 | [Image Smoother](leetcode/0661-image-smoother/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0661-image-smoother/) | [Explanation](leetcode/0661-image-smoother/Explanation.md) |
| 664 | [Strange Printer](leetcode/0664-strange-printer/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0664-strange-printer/) | [Explanation](leetcode/0664-strange-printer/Explanation.md) |
| 668 | [Kth Smallest Number in Multiplication Table](leetcode/0668-kth-smallest-number-in-multiplication-table/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0668-kth-smallest-number-in-multiplication-table/) | [Explanation](leetcode/0668-kth-smallest-number-in-multiplication-table/Explanation.md) |
| 669 | [Trim a Binary Search Tree](leetcode/0669-trim-a-binary-search-tree/) | Medium | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0669-trim-a-binary-search-tree/) | [Explanation](leetcode/0669-trim-a-binary-search-tree/Explanation.md) |
| 670 | [Maximum Swap](leetcode/0670-maximum-swap/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0670-maximum-swap/) | [Explanation](leetcode/0670-maximum-swap/Explanation.md) |
| 671 | [Second Minimum Node In a Binary Tree](leetcode/0671-second-minimum-node-in-a-binary-tree/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0671-second-minimum-node-in-a-binary-tree/) | [Explanation](leetcode/0671-second-minimum-node-in-a-binary-tree/Explanation.md) |
| 672 | [Bulb Switcher II](leetcode/0672-bulb-switcher-ii/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0672-bulb-switcher-ii/) | [Explanation](leetcode/0672-bulb-switcher-ii/Explanation.md) |
| 673 | [Number of Longest Increasing Subsequence](leetcode/0673-number-of-longest-increasing-subsequence/) | Medium | [Dynamic Programming](patterns/dynamic-programming.md) | JavaScript | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/0673-number-of-longest-increasing-subsequence/) | [Explanation](leetcode/0673-number-of-longest-increasing-subsequence/Explanation.md) |
| 674 | [Longest Continuous Increasing Subsequence](leetcode/0674-longest-continuous-increasing-subsequence/) | Easy | [Dynamic Programming](patterns/dynamic-programming.md) | Python | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/0674-longest-continuous-increasing-subsequence/) | [Explanation](leetcode/0674-longest-continuous-increasing-subsequence/Explanation.md) |
| 676 | [Implement Magic Dictionary](leetcode/0676-implement-magic-dictionary/) | Medium | [Trie](patterns/trie.md) | Python | Prefix Tree Lookup | O(n) | O(n) | [Code](leetcode/0676-implement-magic-dictionary/) | [Explanation](leetcode/0676-implement-magic-dictionary/Explanation.md) |
| 677 | [Map Sum Pairs](leetcode/0677-map-sum-pairs/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0677-map-sum-pairs/) | [Explanation](leetcode/0677-map-sum-pairs/Explanation.md) |
| 678 | [Valid Parenthesis String](leetcode/0678-valid-parenthesis-string/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0678-valid-parenthesis-string/) | [Explanation](leetcode/0678-valid-parenthesis-string/Explanation.md) |
| 682 | [Baseball Game](leetcode/0682-baseball-game/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0682-baseball-game/) | [Explanation](leetcode/0682-baseball-game/Explanation.md) |
| 684 | [Redundant Connection](leetcode/0684-redundant-connection/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0684-redundant-connection/) | [Explanation](leetcode/0684-redundant-connection/Explanation.md) |
| 686 | [Repeated String Match](leetcode/0686-repeated-string-match/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0686-repeated-string-match/) | [Explanation](leetcode/0686-repeated-string-match/Explanation.md) |
| 687 | [Longest Univalue Path](leetcode/0687-longest-univalue-path/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0687-longest-univalue-path/) | [Explanation](leetcode/0687-longest-univalue-path/Explanation.md) |
| 688 | [Knight Probability in Chessboard](leetcode/0688-knight-probability-in-chessboard/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0688-knight-probability-in-chessboard/) | [Explanation](leetcode/0688-knight-probability-in-chessboard/Explanation.md) |
| 690 | [Employee Importance](leetcode/0690-employee-importance/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0690-employee-importance/) | [Explanation](leetcode/0690-employee-importance/Explanation.md) |
| 692 | [Top K Frequent Words](leetcode/0692-top-k-frequent-words/) | Medium | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0692-top-k-frequent-words/) | [Explanation](leetcode/0692-top-k-frequent-words/Explanation.md) |
| 693 | [Binary Number with Alternating Bits](leetcode/0693-binary-number-with-alternating-bits/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0693-binary-number-with-alternating-bits/) | [Explanation](leetcode/0693-binary-number-with-alternating-bits/Explanation.md) |
| 695 | [Max Area of Island](leetcode/0695-max-area-of-island/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0695-max-area-of-island/) | [Explanation](leetcode/0695-max-area-of-island/Explanation.md) |
| 696 | [Count Binary Substrings](leetcode/0696-count-binary-substrings/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0696-count-binary-substrings/) | [Explanation](leetcode/0696-count-binary-substrings/Explanation.md) |
| 697 | [Degree of an Array](leetcode/0697-degree-of-an-array/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0697-degree-of-an-array/) | [Explanation](leetcode/0697-degree-of-an-array/Explanation.md) |
| 700 | [Search in a Binary Search Tree](leetcode/0783-search-in-a-binary-search-tree/) | Easy | [Binary Search](patterns/binary-search.md) | JavaScript, Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0783-search-in-a-binary-search-tree/) | [Explanation](leetcode/0783-search-in-a-binary-search-tree/Explanation.md) |
| 703 | [Kth Largest Element in a Stream](leetcode/0789-kth-largest-element-in-a-stream/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0789-kth-largest-element-in-a-stream/) | [Explanation](leetcode/0789-kth-largest-element-in-a-stream/Explanation.md) |
| 704 | [Binary Search](leetcode/0792-binary-search/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(log n) | O(1) | [Code](leetcode/0792-binary-search/) | [Explanation](leetcode/0792-binary-search/Explanation.md) |
| 705 | [Design HashSet](leetcode/0816-design-hashset/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0816-design-hashset/) | [Explanation](leetcode/0816-design-hashset/Explanation.md) |
| 706 | [Design HashMap](leetcode/0817-design-hashmap/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0817-design-hashmap/) | [Explanation](leetcode/0817-design-hashmap/Explanation.md) |
| 709 | [To Lower Case](leetcode/0742-to-lower-case/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0742-to-lower-case/) | [Explanation](leetcode/0742-to-lower-case/Explanation.md) |
| 714 | [Best Time to Buy and Sell Stock with Transaction Fee](leetcode/0714-best-time-to-buy-and-sell-stock-with-transaction-fee/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0714-best-time-to-buy-and-sell-stock-with-transaction-fee/) | [Explanation](leetcode/0714-best-time-to-buy-and-sell-stock-with-transaction-fee/Explanation.md) |
| 717 | [1-bit and 2-bit Characters](leetcode/0717-1-bit-and-2-bit-characters/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0717-1-bit-and-2-bit-characters/) | [Explanation](leetcode/0717-1-bit-and-2-bit-characters/Explanation.md) |
| 718 | [Maximum Length of Repeated Subarray](leetcode/0718-maximum-length-of-repeated-subarray/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0718-maximum-length-of-repeated-subarray/) | [Explanation](leetcode/0718-maximum-length-of-repeated-subarray/Explanation.md) |
| 724 | [Find Pivot Index](leetcode/0724-find-pivot-index/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0724-find-pivot-index/) | [Explanation](leetcode/0724-find-pivot-index/Explanation.md) |
| 728 | [Self Dividing Numbers](leetcode/0728-self-dividing-numbers/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0728-self-dividing-numbers/) | [Explanation](leetcode/0728-self-dividing-numbers/Explanation.md) |
| 733 | [Flood Fill](leetcode/0733-flood-fill/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0733-flood-fill/) | [Explanation](leetcode/0733-flood-fill/Explanation.md) |
| 735 | [Asteroid Collision](leetcode/0735-asteroid-collision/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0735-asteroid-collision/) | [Explanation](leetcode/0735-asteroid-collision/Explanation.md) |
| 739 | [Daily Temperatures](leetcode/0739-daily-temperatures/) | Medium | [Monotonic Stack](patterns/monotonic-stack.md) | JavaScript, TypeScript | Monotonic Stack Filtering | O(n) | O(n) | [Code](leetcode/0739-daily-temperatures/) | [Explanation](leetcode/0739-daily-temperatures/Explanation.md) |
| 743 | [Network Delay Time](leetcode/0744-network-delay-time/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0744-network-delay-time/) | [Explanation](leetcode/0744-network-delay-time/Explanation.md) |
| 744 | [Find Smallest Letter Greater Than Target](leetcode/0745-find-smallest-letter-greater-than-target/) | Easy | [Prefix Sum](patterns/prefix-sum.md) | Python | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/0745-find-smallest-letter-greater-than-target/) | [Explanation](leetcode/0745-find-smallest-letter-greater-than-target/Explanation.md) |
| 746 | [Min Cost Climbing Stairs](leetcode/0747-min-cost-climbing-stairs/) | Easy | [Stack & Queue](patterns/stack-queue.md) | JavaScript, Python | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/0747-min-cost-climbing-stairs/) | [Explanation](leetcode/0747-min-cost-climbing-stairs/Explanation.md) |
| 747 | [Largest Number At Least Twice of Others](leetcode/0748-largest-number-at-least-twice-of-others/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0748-largest-number-at-least-twice-of-others/) | [Explanation](leetcode/0748-largest-number-at-least-twice-of-others/Explanation.md) |
| 748 | [Shortest Completing Word](leetcode/0749-shortest-completing-word/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0749-shortest-completing-word/) | [Explanation](leetcode/0749-shortest-completing-word/Explanation.md) |
| 752 | [Open the Lock](leetcode/0753-open-the-lock/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0753-open-the-lock/) | [Explanation](leetcode/0753-open-the-lock/Explanation.md) |
| 762 | [Prime Number of Set Bits in Binary Representation](leetcode/0767-prime-number-of-set-bits-in-binary-representation/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0767-prime-number-of-set-bits-in-binary-representation/) | [Explanation](leetcode/0767-prime-number-of-set-bits-in-binary-representation/Explanation.md) |
| 763 | [Partition Labels](leetcode/0768-partition-labels/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0768-partition-labels/) | [Explanation](leetcode/0768-partition-labels/Explanation.md) |
| 766 | [Toeplitz Matrix](leetcode/0777-toeplitz-matrix/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0777-toeplitz-matrix/) | [Explanation](leetcode/0777-toeplitz-matrix/Explanation.md) |
| 771 | [Jewels and Stones](leetcode/0782-jewels-and-stones/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0782-jewels-and-stones/) | [Explanation](leetcode/0782-jewels-and-stones/Explanation.md) |
| 773 | [Sliding Puzzle](leetcode/0787-sliding-puzzle/) | Hard | [Sliding Window](patterns/sliding-window.md) | Python | Dynamic Sliding Window Traversal | O(n) | O(1) | [Code](leetcode/0787-sliding-puzzle/) | [Explanation](leetcode/0787-sliding-puzzle/Explanation.md) |
| 778 | [Swim in Rising Water](leetcode/0794-swim-in-rising-water/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0794-swim-in-rising-water/) | [Explanation](leetcode/0794-swim-in-rising-water/Explanation.md) |
| 780 | [Reaching Points](leetcode/0796-reaching-points/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0796-reaching-points/) | [Explanation](leetcode/0796-reaching-points/Explanation.md) |
| 783 | [Minimum Distance Between BST Nodes](leetcode/0799-minimum-distance-between-bst-nodes/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0799-minimum-distance-between-bst-nodes/) | [Explanation](leetcode/0799-minimum-distance-between-bst-nodes/Explanation.md) |
| 788 | [Rotated Digits](leetcode/0804-rotated-digits/) | Medium | [Binary Search](patterns/binary-search.md) | C++ | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0804-rotated-digits/) | [Explanation](leetcode/0804-rotated-digits/Explanation.md) |
| 790 | [Domino and Tromino Tiling](leetcode/0806-domino-and-tromino-tiling/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0806-domino-and-tromino-tiling/) | [Explanation](leetcode/0806-domino-and-tromino-tiling/Explanation.md) |
| 796 | [Rotate String](leetcode/0812-rotate-string/) | Easy | [Math & Logic](patterns/math-logic.md) | C++, JavaScript | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0812-rotate-string/) | [Explanation](leetcode/0812-rotate-string/Explanation.md) |
| 804 | [Unique Morse Code Words](leetcode/0822-unique-morse-code-words/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0822-unique-morse-code-words/) | [Explanation](leetcode/0822-unique-morse-code-words/Explanation.md) |
| 806 | [Number of Lines To Write String](leetcode/0824-number-of-lines-to-write-string/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0824-number-of-lines-to-write-string/) | [Explanation](leetcode/0824-number-of-lines-to-write-string/Explanation.md) |
| 810 | [Chalkboard XOR Game](leetcode/0828-chalkboard-xor-game/) | Hard | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/0828-chalkboard-xor-game/) | [Explanation](leetcode/0828-chalkboard-xor-game/Explanation.md) |
| 812 | [Largest Triangle Area](leetcode/0830-largest-triangle-area/) | Easy | [Math & Logic](patterns/math-logic.md) | Python | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0830-largest-triangle-area/) | [Explanation](leetcode/0830-largest-triangle-area/Explanation.md) |
| 818 | [Race Car](leetcode/0836-race-car/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0836-race-car/) | [Explanation](leetcode/0836-race-car/Explanation.md) |
| 819 | [Most Common Word](leetcode/0837-most-common-word/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0837-most-common-word/) | [Explanation](leetcode/0837-most-common-word/Explanation.md) |
| 821 | [Shortest Distance to a Character](leetcode/0841-shortest-distance-to-a-character/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0841-shortest-distance-to-a-character/) | [Explanation](leetcode/0841-shortest-distance-to-a-character/Explanation.md) |
| 824 | [Goat Latin](leetcode/0851-goat-latin/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0851-goat-latin/) | [Explanation](leetcode/0851-goat-latin/Explanation.md) |
| 830 | [Positions of Large Groups](leetcode/0857-positions-of-large-groups/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0857-positions-of-large-groups/) | [Explanation](leetcode/0857-positions-of-large-groups/Explanation.md) |
| 831 | [Masking Personal Information](leetcode/0858-masking-personal-information/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0858-masking-personal-information/) | [Explanation](leetcode/0858-masking-personal-information/Explanation.md) |
| 832 | [Flipping an Image](leetcode/0861-flipping-an-image/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0861-flipping-an-image/) | [Explanation](leetcode/0861-flipping-an-image/Explanation.md) |
| 835 | [Image Overlap](leetcode/0864-image-overlap/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | JavaScript | Bitwise Masking & Bit Shift | O(n²) | O(1) | [Code](leetcode/0864-image-overlap/) | [Explanation](leetcode/0864-image-overlap/Explanation.md) |
| 836 | [Rectangle Overlap](leetcode/0866-rectangle-overlap/) | Easy | [Math & Logic](patterns/math-logic.md) | JavaScript | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0866-rectangle-overlap/) | [Explanation](leetcode/0866-rectangle-overlap/Explanation.md) |
| 841 | [Keys and Rooms](leetcode/0871-keys-and-rooms/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0871-keys-and-rooms/) | [Explanation](leetcode/0871-keys-and-rooms/Explanation.md) |
| 843 | [Guess the Word](leetcode/0873-guess-the-word/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0873-guess-the-word/) | [Explanation](leetcode/0873-guess-the-word/Explanation.md) |
| 844 | [Backspace String Compare](leetcode/0874-backspace-string-compare/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0874-backspace-string-compare/) | [Explanation](leetcode/0874-backspace-string-compare/Explanation.md) |
| 850 | [Rectangle Area II](leetcode/0880-rectangle-area-ii/) | Hard | [Math & Logic](patterns/math-logic.md) | Python | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/0880-rectangle-area-ii/) | [Explanation](leetcode/0880-rectangle-area-ii/Explanation.md) |
| 852 | [Peak Index in a Mountain Array](leetcode/0882-peak-index-in-a-mountain-array/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript, Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0882-peak-index-in-a-mountain-array/) | [Explanation](leetcode/0882-peak-index-in-a-mountain-array/Explanation.md) |
| 856 | [Score of Parentheses](leetcode/0886-score-of-parentheses/) | Medium | [Stack & Queue](patterns/stack-queue.md) | Python | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/0886-score-of-parentheses/) | [Explanation](leetcode/0886-score-of-parentheses/Explanation.md) |
| 858 | [Mirror Reflection](leetcode/0888-mirror-reflection/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0888-mirror-reflection/) | [Explanation](leetcode/0888-mirror-reflection/Explanation.md) |
| 859 | [Buddy Strings](leetcode/0889-buddy-strings/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0889-buddy-strings/) | [Explanation](leetcode/0889-buddy-strings/Explanation.md) |
| 860 | [Lemonade Change](leetcode/0890-lemonade-change/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0890-lemonade-change/) | [Explanation](leetcode/0890-lemonade-change/Explanation.md) |
| 865 | [Smallest Subtree with all the Deepest Nodes](leetcode/0896-smallest-subtree-with-all-the-deepest-nodes/) | Medium | [Two Pointers](patterns/two-pointers.md) | JavaScript | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0896-smallest-subtree-with-all-the-deepest-nodes/) | [Explanation](leetcode/0896-smallest-subtree-with-all-the-deepest-nodes/Explanation.md) |
| 867 | [Transpose Matrix](leetcode/0898-transpose-matrix/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0898-transpose-matrix/) | [Explanation](leetcode/0898-transpose-matrix/Explanation.md) |
| 868 | [Binary Gap](leetcode/0899-binary-gap/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0899-binary-gap/) | [Explanation](leetcode/0899-binary-gap/Explanation.md) |
| 872 | [Leaf-Similar Trees](leetcode/0904-leaf-similar-trees/) | Easy | [Binary Search](patterns/binary-search.md) | JavaScript, Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0904-leaf-similar-trees/) | [Explanation](leetcode/0904-leaf-similar-trees/Explanation.md) |
| 875 | [Koko Eating Bananas](leetcode/0907-koko-eating-bananas/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0907-koko-eating-bananas/) | [Explanation](leetcode/0907-koko-eating-bananas/Explanation.md) |
| 876 | [Middle of the Linked List](leetcode/0908-middle-of-the-linked-list/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0908-middle-of-the-linked-list/) | [Explanation](leetcode/0908-middle-of-the-linked-list/Explanation.md) |
| 877 | [Stone Game](leetcode/0909-stone-game/) | Medium | [Tree & Graph](patterns/tree-graph.md) | C++ | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0909-stone-game/) | [Explanation](leetcode/0909-stone-game/Explanation.md) |
| 878 | [Nth Magical Number](leetcode/0910-nth-magical-number/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0910-nth-magical-number/) | [Explanation](leetcode/0910-nth-magical-number/Explanation.md) |
| 882 | [Reachable Nodes In Subdivided Graph](leetcode/0918-reachable-nodes-in-subdivided-graph/) | Hard | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0918-reachable-nodes-in-subdivided-graph/) | [Explanation](leetcode/0918-reachable-nodes-in-subdivided-graph/Explanation.md) |
| 883 | [Projection Area of 3D Shapes](leetcode/0919-projection-area-of-3d-shapes/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0919-projection-area-of-3d-shapes/) | [Explanation](leetcode/0919-projection-area-of-3d-shapes/Explanation.md) |
| 884 | [Uncommon Words from Two Sentences](leetcode/0920-uncommon-words-from-two-sentences/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0920-uncommon-words-from-two-sentences/) | [Explanation](leetcode/0920-uncommon-words-from-two-sentences/Explanation.md) |
| 888 | [Fair Candy Swap](leetcode/0924-fair-candy-swap/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0924-fair-candy-swap/) | [Explanation](leetcode/0924-fair-candy-swap/Explanation.md) |
| 892 | [Surface Area of 3D Shapes](leetcode/0928-surface-area-of-3d-shapes/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0928-surface-area-of-3d-shapes/) | [Explanation](leetcode/0928-surface-area-of-3d-shapes/Explanation.md) |
| 896 | [Monotonic Array](leetcode/0932-monotonic-array/) | Easy | [Monotonic Stack](patterns/monotonic-stack.md) | Python | Monotonic Stack Filtering | O(n) | O(n) | [Code](leetcode/0932-monotonic-array/) | [Explanation](leetcode/0932-monotonic-array/Explanation.md) |
| 897 | [Increasing Order Search Tree](leetcode/0933-increasing-order-search-tree/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0933-increasing-order-search-tree/) | [Explanation](leetcode/0933-increasing-order-search-tree/Explanation.md) |
| 901 | [Online Stock Span](leetcode/0937-online-stock-span/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0937-online-stock-span/) | [Explanation](leetcode/0937-online-stock-span/Explanation.md) |
| 905 | [Sort Array By Parity](leetcode/0941-sort-array-by-parity/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0941-sort-array-by-parity/) | [Explanation](leetcode/0941-sort-array-by-parity/Explanation.md) |
| 908 | [Smallest Range I](leetcode/0944-smallest-range-i/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0944-smallest-range-i/) | [Explanation](leetcode/0944-smallest-range-i/Explanation.md) |
| 909 | [Snakes and Ladders](leetcode/0945-snakes-and-ladders/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0945-snakes-and-ladders/) | [Explanation](leetcode/0945-snakes-and-ladders/Explanation.md) |
| 912 | [Sort an Array](leetcode/0948-sort-an-array/) | Medium | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0948-sort-an-array/) | [Explanation](leetcode/0948-sort-an-array/Explanation.md) |
| 913 | [Cat and Mouse](leetcode/0949-cat-and-mouse/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0949-cat-and-mouse/) | [Explanation](leetcode/0949-cat-and-mouse/Explanation.md) |
| 914 | [X of a Kind in a Deck of Cards](leetcode/0950-x-of-a-kind-in-a-deck-of-cards/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0950-x-of-a-kind-in-a-deck-of-cards/) | [Explanation](leetcode/0950-x-of-a-kind-in-a-deck-of-cards/Explanation.md) |
| 917 | [Reverse Only Letters](leetcode/0953-reverse-only-letters/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/0953-reverse-only-letters/) | [Explanation](leetcode/0953-reverse-only-letters/Explanation.md) |
| 918 | [Maximum Sum Circular Subarray](leetcode/0954-maximum-sum-circular-subarray/) | Medium | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/0954-maximum-sum-circular-subarray/) | [Explanation](leetcode/0954-maximum-sum-circular-subarray/Explanation.md) |
| 921 | [Minimum Add to Make Parentheses Valid](leetcode/0957-minimum-add-to-make-parentheses-valid/) | Medium | [Stack & Queue](patterns/stack-queue.md) | Python | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/0957-minimum-add-to-make-parentheses-valid/) | [Explanation](leetcode/0957-minimum-add-to-make-parentheses-valid/Explanation.md) |
| 922 | [Sort Array By Parity II](leetcode/0958-sort-array-by-parity-ii/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0958-sort-array-by-parity-ii/) | [Explanation](leetcode/0958-sort-array-by-parity-ii/Explanation.md) |
| 925 | [Long Pressed Name](leetcode/0961-long-pressed-name/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0961-long-pressed-name/) | [Explanation](leetcode/0961-long-pressed-name/Explanation.md) |
| 929 | [Unique Email Addresses](leetcode/0965-unique-email-addresses/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0965-unique-email-addresses/) | [Explanation](leetcode/0965-unique-email-addresses/Explanation.md) |
| 932 | [Beautiful Array](leetcode/0968-beautiful-array/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0968-beautiful-array/) | [Explanation](leetcode/0968-beautiful-array/Explanation.md) |
| 933 | [Number of Recent Calls](leetcode/0969-number-of-recent-calls/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0969-number-of-recent-calls/) | [Explanation](leetcode/0969-number-of-recent-calls/Explanation.md) |
| 938 | [Range Sum of BST](leetcode/0975-range-sum-of-bst/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/0975-range-sum-of-bst/) | [Explanation](leetcode/0975-range-sum-of-bst/Explanation.md) |
| 940 | [Distinct Subsequences II](leetcode/0977-distinct-subsequences-ii/) | Hard | [Dynamic Programming](patterns/dynamic-programming.md) | JavaScript | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/0977-distinct-subsequences-ii/) | [Explanation](leetcode/0977-distinct-subsequences-ii/Explanation.md) |
| 941 | [Valid Mountain Array](leetcode/0978-valid-mountain-array/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0978-valid-mountain-array/) | [Explanation](leetcode/0978-valid-mountain-array/Explanation.md) |
| 942 | [DI String Match](leetcode/0979-di-string-match/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0979-di-string-match/) | [Explanation](leetcode/0979-di-string-match/Explanation.md) |
| 944 | [Delete Columns to Make Sorted](leetcode/0981-delete-columns-to-make-sorted/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/0981-delete-columns-to-make-sorted/) | [Explanation](leetcode/0981-delete-columns-to-make-sorted/Explanation.md) |
| 953 | [Verifying an Alien Dictionary](leetcode/0990-verifying-an-alien-dictionary/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/0990-verifying-an-alien-dictionary/) | [Explanation](leetcode/0990-verifying-an-alien-dictionary/Explanation.md) |
| 961 | [N-Repeated Element in Size 2N Array](leetcode/1001-n-repeated-element-in-size-2n-array/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1001-n-repeated-element-in-size-2n-array/) | [Explanation](leetcode/1001-n-repeated-element-in-size-2n-array/Explanation.md) |
| 965 | [Univalued Binary Tree](leetcode/1005-univalued-binary-tree/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/1005-univalued-binary-tree/) | [Explanation](leetcode/1005-univalued-binary-tree/Explanation.md) |
| 976 | [Largest Perimeter Triangle](leetcode/1018-largest-perimeter-triangle/) | Easy | [Math & Logic](patterns/math-logic.md) | Python | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/1018-largest-perimeter-triangle/) | [Explanation](leetcode/1018-largest-perimeter-triangle/Explanation.md) |
| 977 | [Squares of a Sorted Array](leetcode/1019-squares-of-a-sorted-array/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1019-squares-of-a-sorted-array/) | [Explanation](leetcode/1019-squares-of-a-sorted-array/Explanation.md) |
| 981 | [Time Based Key-Value Store](leetcode/1023-time-based-key-value-store/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1023-time-based-key-value-store/) | [Explanation](leetcode/1023-time-based-key-value-store/Explanation.md) |
| 986 | [Interval List Intersections](leetcode/1028-interval-list-intersections/) | Medium | [Heap](patterns/heap.md) | Python | Min/Max Heap Priority Selection | O(n) | O(n) | [Code](leetcode/1028-interval-list-intersections/) | [Explanation](leetcode/1028-interval-list-intersections/Explanation.md) |
| 989 | [Add to Array-Form of Integer](leetcode/1031-add-to-array-form-of-integer/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1031-add-to-array-form-of-integer/) | [Explanation](leetcode/1031-add-to-array-form-of-integer/Explanation.md) |
| 993 | [Cousins in Binary Tree](leetcode/1035-cousins-in-binary-tree/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/1035-cousins-in-binary-tree/) | [Explanation](leetcode/1035-cousins-in-binary-tree/Explanation.md) |
| 994 | [Rotting Oranges](leetcode/1036-rotting-oranges/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1036-rotting-oranges/) | [Explanation](leetcode/1036-rotting-oranges/Explanation.md) |
| 997 | [Find the Town Judge](leetcode/1039-find-the-town-judge/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1039-find-the-town-judge/) | [Explanation](leetcode/1039-find-the-town-judge/Explanation.md) |
| 999 | [Available Captures for Rook](leetcode/1041-available-captures-for-rook/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1041-available-captures-for-rook/) | [Explanation](leetcode/1041-available-captures-for-rook/Explanation.md) |
| 1002 | [Find Common Characters](leetcode/1044-find-common-characters/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1044-find-common-characters/) | [Explanation](leetcode/1044-find-common-characters/Explanation.md) |
| 1004 | [Max Consecutive Ones III](leetcode/1046-max-consecutive-ones-iii/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1046-max-consecutive-ones-iii/) | [Explanation](leetcode/1046-max-consecutive-ones-iii/Explanation.md) |
| 1005 | [Maximize Sum Of Array After K Negations](leetcode/1047-maximize-sum-of-array-after-k-negations/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1047-maximize-sum-of-array-after-k-negations/) | [Explanation](leetcode/1047-maximize-sum-of-array-after-k-negations/Explanation.md) |
| 1009 | [Complement of Base 10 Integer](leetcode/1054-complement-of-base-10-integer/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1054-complement-of-base-10-integer/) | [Explanation](leetcode/1054-complement-of-base-10-integer/Explanation.md) |
| 1015 | [Smallest Integer Divisible by K](leetcode/1064-smallest-integer-divisible-by-k/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/1064-smallest-integer-divisible-by-k/) | [Explanation](leetcode/1064-smallest-integer-divisible-by-k/Explanation.md) |
| 1018 | [Binary Prefix Divisible By 5](leetcode/1071-binary-prefix-divisible-by-5/) | Easy | [Prefix Sum](patterns/prefix-sum.md) | Python | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/1071-binary-prefix-divisible-by-5/) | [Explanation](leetcode/1071-binary-prefix-divisible-by-5/Explanation.md) |
| 1021 | [Remove Outermost Parentheses](leetcode/1078-remove-outermost-parentheses/) | Easy | [Stack & Queue](patterns/stack-queue.md) | Python | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/1078-remove-outermost-parentheses/) | [Explanation](leetcode/1078-remove-outermost-parentheses/Explanation.md) |
| 1022 | [Sum of Root To Leaf Binary Numbers](leetcode/1079-sum-of-root-to-leaf-binary-numbers/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1079-sum-of-root-to-leaf-binary-numbers/) | [Explanation](leetcode/1079-sum-of-root-to-leaf-binary-numbers/Explanation.md) |
| 1025 | [Divisor Game](leetcode/1086-divisor-game/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1086-divisor-game/) | [Explanation](leetcode/1086-divisor-game/Explanation.md) |
| 1030 | [Matrix Cells in Distance Order](leetcode/1094-matrix-cells-in-distance-order/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1094-matrix-cells-in-distance-order/) | [Explanation](leetcode/1094-matrix-cells-in-distance-order/Explanation.md) |
| 1033 | [Moving Stones Until Consecutive](leetcode/1103-moving-stones-until-consecutive/) | Medium | [Dynamic Programming](patterns/dynamic-programming.md) | Python | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/1103-moving-stones-until-consecutive/) | [Explanation](leetcode/1103-moving-stones-until-consecutive/Explanation.md) |
| 1036 | [Escape a Large Maze](leetcode/1106-escape-a-large-maze/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1106-escape-a-large-maze/) | [Explanation](leetcode/1106-escape-a-large-maze/Explanation.md) |
| 1037 | [Valid Boomerang](leetcode/1115-valid-boomerang/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1115-valid-boomerang/) | [Explanation](leetcode/1115-valid-boomerang/Explanation.md) |
| 1044 | [Longest Duplicate Substring](leetcode/1122-longest-duplicate-substring/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1122-longest-duplicate-substring/) | [Explanation](leetcode/1122-longest-duplicate-substring/Explanation.md) |
| 1045 | [Customers Who Bought All Products](leetcode/1135-customers-who-bought-all-products/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1135-customers-who-bought-all-products/) | [Explanation](leetcode/1135-customers-who-bought-all-products/Explanation.md) |
| 1046 | [Last Stone Weight](leetcode/1127-last-stone-weight/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1127-last-stone-weight/) | [Explanation](leetcode/1127-last-stone-weight/Explanation.md) |
| 1047 | [Remove All Adjacent Duplicates In String](leetcode/1128-remove-all-adjacent-duplicates-in-string/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1128-remove-all-adjacent-duplicates-in-string/) | [Explanation](leetcode/1128-remove-all-adjacent-duplicates-in-string/Explanation.md) |
| 1050 | [Actors and Directors Who Cooperated At Least Three Times](leetcode/1136-actors-and-directors-who-cooperated-at-least-three-times/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1136-actors-and-directors-who-cooperated-at-least-three-times/) | [Explanation](leetcode/1136-actors-and-directors-who-cooperated-at-least-three-times/Explanation.md) |
| 1051 | [Height Checker](leetcode/1137-height-checker/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1137-height-checker/) | [Explanation](leetcode/1137-height-checker/Explanation.md) |
| 1068 | [Product Sales Analysis I](leetcode/1153-product-sales-analysis-i/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1153-product-sales-analysis-i/) | [Explanation](leetcode/1153-product-sales-analysis-i/Explanation.md) |
| 1070 | [Product Sales Analysis III](leetcode/1155-product-sales-analysis-iii/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1155-product-sales-analysis-iii/) | [Explanation](leetcode/1155-product-sales-analysis-iii/Explanation.md) |
| 1071 | [Greatest Common Divisor of Strings](leetcode/1146-greatest-common-divisor-of-strings/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1146-greatest-common-divisor-of-strings/) | [Explanation](leetcode/1146-greatest-common-divisor-of-strings/Explanation.md) |
| 1075 | [Project Employees I](leetcode/1161-project-employees-i/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1161-project-employees-i/) | [Explanation](leetcode/1161-project-employees-i/Explanation.md) |
| 1078 | [Occurrences After Bigram](leetcode/1156-occurrences-after-bigram/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1156-occurrences-after-bigram/) | [Explanation](leetcode/1156-occurrences-after-bigram/Explanation.md) |
| 1081 | [Smallest Subsequence of Distinct Characters](leetcode/1159-smallest-subsequence-of-distinct-characters/) | Medium | [Monotonic Stack](patterns/monotonic-stack.md) | C++ | Monotonic Stack Filtering | O(n) | O(n) | [Code](leetcode/1159-smallest-subsequence-of-distinct-characters/) | [Explanation](leetcode/1159-smallest-subsequence-of-distinct-characters/Explanation.md) |
| 1084 | [Sales Analysis III](leetcode/1174-sales-analysis-iii/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1174-sales-analysis-iii/) | [Explanation](leetcode/1174-sales-analysis-iii/Explanation.md) |
| 1089 | [Duplicate Zeros](leetcode/1168-duplicate-zeros/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1168-duplicate-zeros/) | [Explanation](leetcode/1168-duplicate-zeros/Explanation.md) |
| 1096 | [Brace Expansion II](leetcode/1188-brace-expansion-ii/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1188-brace-expansion-ii/) | [Explanation](leetcode/1188-brace-expansion-ii/Explanation.md) |
| 1103 | [Distribute Candies to People](leetcode/1195-distribute-candies-to-people/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1195-distribute-candies-to-people/) | [Explanation](leetcode/1195-distribute-candies-to-people/Explanation.md) |
| 1108 | [Defanging an IP Address](leetcode/1205-defanging-an-ip-address/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1205-defanging-an-ip-address/) | [Explanation](leetcode/1205-defanging-an-ip-address/Explanation.md) |
| 1111 | [Maximum Nesting Depth of Two Valid Parentheses Strings](leetcode/1208-maximum-nesting-depth-of-two-valid-parentheses-strings/) | Medium | [Stack & Queue](patterns/stack-queue.md) | C++ | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/1208-maximum-nesting-depth-of-two-valid-parentheses-strings/) | [Explanation](leetcode/1208-maximum-nesting-depth-of-two-valid-parentheses-strings/Explanation.md) |
| 1114 | [Print in Order](leetcode/1203-print-in-order/) | Easy | [Hash Map](patterns/hash-map.md) | Java | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1203-print-in-order/) | [Explanation](leetcode/1203-print-in-order/Explanation.md) |
| 1115 | [Print FooBar Alternately](leetcode/1187-print-foobar-alternately/) | Medium | [Hash Map](patterns/hash-map.md) | Java | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1187-print-foobar-alternately/) | [Explanation](leetcode/1187-print-foobar-alternately/Explanation.md) |
| 1116 | [Print Zero Even Odd](leetcode/1216-print-zero-even-odd/) | Medium | [Two Pointers](patterns/two-pointers.md) | Java | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/1216-print-zero-even-odd/) | [Explanation](leetcode/1216-print-zero-even-odd/Explanation.md) |
| 1117 | [Building H2O](leetcode/1186-building-h2o/) | Medium | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1186-building-h2o/) | [Explanation](leetcode/1186-building-h2o/Explanation.md) |
| 1122 | [Relative Sort Array](leetcode/1217-relative-sort-array/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1217-relative-sort-array/) | [Explanation](leetcode/1217-relative-sort-array/Explanation.md) |
| 1123 | [Lowest Common Ancestor of Deepest Leaves](leetcode/1218-lowest-common-ancestor-of-deepest-leaves/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/1218-lowest-common-ancestor-of-deepest-leaves/) | [Explanation](leetcode/1218-lowest-common-ancestor-of-deepest-leaves/Explanation.md) |
| 1128 | [Number of Equivalent Domino Pairs](leetcode/1227-number-of-equivalent-domino-pairs/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1227-number-of-equivalent-domino-pairs/) | [Explanation](leetcode/1227-number-of-equivalent-domino-pairs/Explanation.md) |
| 1137 | [N-th Tribonacci Number](leetcode/1236-n-th-tribonacci-number/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | JavaScript, Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/1236-n-th-tribonacci-number/) | [Explanation](leetcode/1236-n-th-tribonacci-number/Explanation.md) |
| 1140 | [Stone Game II](leetcode/1240-stone-game-ii/) | Medium | [Dynamic Programming](patterns/dynamic-programming.md) | C++ | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/1240-stone-game-ii/) | [Explanation](leetcode/1240-stone-game-ii/Explanation.md) |
| 1141 | [User Activity for the Past 30 Days I](leetcode/1245-user-activity-for-the-past-30-days-i/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1245-user-activity-for-the-past-30-days-i/) | [Explanation](leetcode/1245-user-activity-for-the-past-30-days-i/Explanation.md) |
| 1143 | [Longest Common Subsequence](leetcode/1250-longest-common-subsequence/) | Medium | [Dynamic Programming](patterns/dynamic-programming.md) | JavaScript | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/1250-longest-common-subsequence/) | [Explanation](leetcode/1250-longest-common-subsequence/Explanation.md) |
| 1146 | [Snapshot Array](leetcode/1249-snapshot-array/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1249-snapshot-array/) | [Explanation](leetcode/1249-snapshot-array/Explanation.md) |
| 1147 | [Longest Chunked Palindrome Decomposition](leetcode/1251-longest-chunked-palindrome-decomposition/) | Hard | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/1251-longest-chunked-palindrome-decomposition/) | [Explanation](leetcode/1251-longest-chunked-palindrome-decomposition/Explanation.md) |
| 1148 | [Article Views I](leetcode/1258-article-views-i/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1258-article-views-i/) | [Explanation](leetcode/1258-article-views-i/Explanation.md) |
| 1154 | [Day of the Year](leetcode/1260-day-of-the-year/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1260-day-of-the-year/) | [Explanation](leetcode/1260-day-of-the-year/Explanation.md) |
| 1157 | [Online Majority Element In Subarray](leetcode/1262-online-majority-element-in-subarray/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1262-online-majority-element-in-subarray/) | [Explanation](leetcode/1262-online-majority-element-in-subarray/Explanation.md) |
| 1158 | [Market Analysis I](leetcode/1268-market-analysis-i/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1268-market-analysis-i/) | [Explanation](leetcode/1268-market-analysis-i/Explanation.md) |
| 1160 | [Find Words That Can Be Formed by Characters](leetcode/1112-find-words-that-can-be-formed-by-characters/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1112-find-words-that-can-be-formed-by-characters/) | [Explanation](leetcode/1112-find-words-that-can-be-formed-by-characters/Explanation.md) |
| 1161 | [Maximum Level Sum of a Binary Tree](leetcode/1116-maximum-level-sum-of-a-binary-tree/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/1116-maximum-level-sum-of-a-binary-tree/) | [Explanation](leetcode/1116-maximum-level-sum-of-a-binary-tree/Explanation.md) |
| 1164 | [Product Price at a Given Date](leetcode/1278-product-price-at-a-given-date/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1278-product-price-at-a-given-date/) | [Explanation](leetcode/1278-product-price-at-a-given-date/Explanation.md) |
| 1174 | [Immediate Food Delivery II](leetcode/1292-immediate-food-delivery-ii/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1292-immediate-food-delivery-ii/) | [Explanation](leetcode/1292-immediate-food-delivery-ii/Explanation.md) |
| 1175 | [Prime Arrangements](leetcode/1279-prime-arrangements/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/1279-prime-arrangements/) | [Explanation](leetcode/1279-prime-arrangements/Explanation.md) |
| 1179 | [Reformat Department Table](leetcode/1301-reformat-department-table/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1301-reformat-department-table/) | [Explanation](leetcode/1301-reformat-department-table/Explanation.md) |
| 1185 | [Day of the Week](leetcode/1289-day-of-the-week/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1289-day-of-the-week/) | [Explanation](leetcode/1289-day-of-the-week/Explanation.md) |
| 1189 | [Maximum Number of Balloons](leetcode/1297-maximum-number-of-balloons/) | Easy | [Hash Map](patterns/hash-map.md) | Kotlin | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1297-maximum-number-of-balloons/) | [Explanation](leetcode/1297-maximum-number-of-balloons/Explanation.md) |
| 1190 | [Reverse Substrings Between Each Pair of Parentheses](leetcode/1298-reverse-substrings-between-each-pair-of-parentheses/) | Medium | [Stack & Queue](patterns/stack-queue.md) | C++ | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/1298-reverse-substrings-between-each-pair-of-parentheses/) | [Explanation](leetcode/1298-reverse-substrings-between-each-pair-of-parentheses/Explanation.md) |
| 1193 | [Monthly Transactions I](leetcode/1317-monthly-transactions-i/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1317-monthly-transactions-i/) | [Explanation](leetcode/1317-monthly-transactions-i/Explanation.md) |
| 1195 | [Fizz Buzz Multithreaded](leetcode/1316-fizz-buzz-multithreaded/) | Medium | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1316-fizz-buzz-multithreaded/) | [Explanation](leetcode/1316-fizz-buzz-multithreaded/Explanation.md) |
| 1200 | [Minimum Absolute Difference](leetcode/1306-minimum-absolute-difference/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1306-minimum-absolute-difference/) | [Explanation](leetcode/1306-minimum-absolute-difference/Explanation.md) |
| 1201 | [Ugly Number III](leetcode/1307-ugly-number-iii/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1307-ugly-number-iii/) | [Explanation](leetcode/1307-ugly-number-iii/Explanation.md) |
| 1204 | [Last Person to Fit in the Bus](leetcode/1327-last-person-to-fit-in-the-bus/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1327-last-person-to-fit-in-the-bus/) | [Explanation](leetcode/1327-last-person-to-fit-in-the-bus/Explanation.md) |
| 1207 | [Unique Number of Occurrences](leetcode/1319-unique-number-of-occurrences/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1319-unique-number-of-occurrences/) | [Explanation](leetcode/1319-unique-number-of-occurrences/Explanation.md) |
| 1211 | [Queries Quality and Percentage](leetcode/1338-queries-quality-and-percentage/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1338-queries-quality-and-percentage/) | [Explanation](leetcode/1338-queries-quality-and-percentage/Explanation.md) |
| 1217 | [Minimum Cost to Move Chips to The Same Position](leetcode/1329-minimum-cost-to-move-chips-to-the-same-position/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1329-minimum-cost-to-move-chips-to-the-same-position/) | [Explanation](leetcode/1329-minimum-cost-to-move-chips-to-the-same-position/Explanation.md) |
| 1221 | [Split a String in Balanced Strings](leetcode/1341-split-a-string-in-balanced-strings/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1341-split-a-string-in-balanced-strings/) | [Explanation](leetcode/1341-split-a-string-in-balanced-strings/Explanation.md) |
| 1226 | [The Dining Philosophers](leetcode/1340-the-dining-philosophers/) | Medium | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1340-the-dining-philosophers/) | [Explanation](leetcode/1340-the-dining-philosophers/Explanation.md) |
| 1227 | [Airplane Seat Assignment Probability](leetcode/1362-airplane-seat-assignment-probability/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1362-airplane-seat-assignment-probability/) | [Explanation](leetcode/1362-airplane-seat-assignment-probability/Explanation.md) |
| 1232 | [Check If It Is a Straight Line](leetcode/1349-check-if-it-is-a-straight-line/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1349-check-if-it-is-a-straight-line/) | [Explanation](leetcode/1349-check-if-it-is-a-straight-line/Explanation.md) |
| 1250 | [Check If It Is a Good Array](leetcode/1372-check-if-it-is-a-good-array/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1372-check-if-it-is-a-good-array/) | [Explanation](leetcode/1372-check-if-it-is-a-good-array/Explanation.md) |
| 1251 | [Average Selling Price](leetcode/1390-average-selling-price/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1390-average-selling-price/) | [Explanation](leetcode/1390-average-selling-price/Explanation.md) |
| 1252 | [Cells with Odd Values in a Matrix](leetcode/1378-cells-with-odd-values-in-a-matrix/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1378-cells-with-odd-values-in-a-matrix/) | [Explanation](leetcode/1378-cells-with-odd-values-in-a-matrix/Explanation.md) |
| 1260 | [Shift 2D Grid](leetcode/1386-shift-2d-grid/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Racket | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1386-shift-2d-grid/) | [Explanation](leetcode/1386-shift-2d-grid/Explanation.md) |
| 1266 | [Minimum Time Visiting All Points](leetcode/1395-minimum-time-visiting-all-points/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1395-minimum-time-visiting-all-points/) | [Explanation](leetcode/1395-minimum-time-visiting-all-points/Explanation.md) |
| 1268 | [Search Suggestions System](leetcode/1397-search-suggestions-system/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1397-search-suggestions-system/) | [Explanation](leetcode/1397-search-suggestions-system/Explanation.md) |
| 1275 | [Find Winner on a Tic Tac Toe Game](leetcode/1400-find-winner-on-a-tic-tac-toe-game/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1400-find-winner-on-a-tic-tac-toe-game/) | [Explanation](leetcode/1400-find-winner-on-a-tic-tac-toe-game/Explanation.md) |
| 1280 | [Students and Examinations](leetcode/1415-students-and-examinations/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1415-students-and-examinations/) | [Explanation](leetcode/1415-students-and-examinations/Explanation.md) |
| 1281 | [Subtract the Product and Sum of Digits of an Integer](leetcode/1406-subtract-the-product-and-sum-of-digits-of-an-integer/) | Easy | [Math & Logic](patterns/math-logic.md) | Python | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/1406-subtract-the-product-and-sum-of-digits-of-an-integer/) | [Explanation](leetcode/1406-subtract-the-product-and-sum-of-digits-of-an-integer/Explanation.md) |
| 1287 | [Element Appearing More Than 25% In Sorted Array](leetcode/1221-element-appearing-more-than-25-in-sorted-array/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1221-element-appearing-more-than-25-in-sorted-array/) | [Explanation](leetcode/1221-element-appearing-more-than-25-in-sorted-array/Explanation.md) |
| 1288 | [Remove Covered Intervals](leetcode/1222-remove-covered-intervals/) | Medium | [Binary Search](patterns/binary-search.md) | Java | Modified Binary Search | O(log n) | O(1) | [Code](leetcode/1222-remove-covered-intervals/) | [Explanation](leetcode/1222-remove-covered-intervals/Explanation.md) |
| 1290 | [Convert Binary Number in a Linked List to Integer](leetcode/1411-convert-binary-number-in-a-linked-list-to-integer/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/1411-convert-binary-number-in-a-linked-list-to-integer/) | [Explanation](leetcode/1411-convert-binary-number-in-a-linked-list-to-integer/Explanation.md) |
| 1291 | [Sequential Digits](leetcode/1212-sequential-digits/) | Medium | [Prefix Sum](patterns/prefix-sum.md) | C++ | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/1212-sequential-digits/) | [Explanation](leetcode/1212-sequential-digits/Explanation.md) |
| 1295 | [Find Numbers with Even Number of Digits](leetcode/1421-find-numbers-with-even-number-of-digits/) | Easy | [Math & Logic](patterns/math-logic.md) | Python | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/1421-find-numbers-with-even-number-of-digits/) | [Explanation](leetcode/1421-find-numbers-with-even-number-of-digits/Explanation.md) |
| 1299 | [Replace Elements with Greatest Element on Right Side](leetcode/1231-replace-elements-with-greatest-element-on-right-side/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1231-replace-elements-with-greatest-element-on-right-side/) | [Explanation](leetcode/1231-replace-elements-with-greatest-element-on-right-side/Explanation.md) |
| 1301 | [Number of Paths with Max Score](leetcode/1234-number-of-paths-with-max-score/) | Hard | [Dynamic Programming](patterns/dynamic-programming.md) | PHP | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/1234-number-of-paths-with-max-score/) | [Explanation](leetcode/1234-number-of-paths-with-max-score/Explanation.md) |
| 1306 | [Jump Game III](leetcode/1428-jump-game-iii/) | Medium | [Tree & Graph](patterns/tree-graph.md) | C++ | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1428-jump-game-iii/) | [Explanation](leetcode/1428-jump-game-iii/Explanation.md) |
| 1309 | [Decrypt String from Alphabet to Integer Mapping](leetcode/1434-decrypt-string-from-alphabet-to-integer-mapping/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1434-decrypt-string-from-alphabet-to-integer-mapping/) | [Explanation](leetcode/1434-decrypt-string-from-alphabet-to-integer-mapping/Explanation.md) |
| 1313 | [Decompress Run-Length Encoded List](leetcode/1241-decompress-run-length-encoded-list/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1241-decompress-run-length-encoded-list/) | [Explanation](leetcode/1241-decompress-run-length-encoded-list/Explanation.md) |
| 1316 | [Distinct Echo Substrings](leetcode/1244-distinct-echo-substrings/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1244-distinct-echo-substrings/) | [Explanation](leetcode/1244-distinct-echo-substrings/Explanation.md) |
| 1317 | [Convert Integer to the Sum of Two No-Zero Integers](leetcode/1440-convert-integer-to-the-sum-of-two-no-zero-integers/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1440-convert-integer-to-the-sum-of-two-no-zero-integers/) | [Explanation](leetcode/1440-convert-integer-to-the-sum-of-two-no-zero-integers/Explanation.md) |
| 1318 | [Minimum Flips to Make a OR b Equal to c](leetcode/1441-minimum-flips-to-make-a-or-b-equal-to-c/) | Medium | [Hash Map](patterns/hash-map.md) | JavaScript | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1441-minimum-flips-to-make-a-or-b-equal-to-c/) | [Explanation](leetcode/1441-minimum-flips-to-make-a-or-b-equal-to-c/Explanation.md) |
| 1321 | [Restaurant Growth](leetcode/1452-restaurant-growth/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1452-restaurant-growth/) | [Explanation](leetcode/1452-restaurant-growth/Explanation.md) |
| 1323 | [Maximum 69 Number](leetcode/1448-maximum-69-number/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1448-maximum-69-number/) | [Explanation](leetcode/1448-maximum-69-number/Explanation.md) |
| 1327 | [List the Products Ordered in a Period](leetcode/1462-list-the-products-ordered-in-a-period/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1462-list-the-products-ordered-in-a-period/) | [Explanation](leetcode/1462-list-the-products-ordered-in-a-period/Explanation.md) |
| 1331 | [Rank Transform of an Array](leetcode/1256-rank-transform-of-an-array/) | Easy | [Binary Search](patterns/binary-search.md) | Kotlin | Modified Binary Search | O(n) | O(1) | [Code](leetcode/1256-rank-transform-of-an-array/) | [Explanation](leetcode/1256-rank-transform-of-an-array/Explanation.md) |
| 1332 | [Remove Palindromic Subsequences](leetcode/1454-remove-palindromic-subsequences/) | Easy | [Dynamic Programming](patterns/dynamic-programming.md) | Python | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/1454-remove-palindromic-subsequences/) | [Explanation](leetcode/1454-remove-palindromic-subsequences/Explanation.md) |
| 1334 | [Find the City With the Smallest Number of Neighbors at a Threshold Distance](leetcode/1456-find-the-city-with-the-smallest-number-of-neighbors-at-a-threshold-distance/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1456-find-the-city-with-the-smallest-number-of-neighbors-at-a-threshold-distance/) | [Explanation](leetcode/1456-find-the-city-with-the-smallest-number-of-neighbors-at-a-threshold-distance/Explanation.md) |
| 1337 | [The K Weakest Rows in a Matrix](leetcode/1463-the-k-weakest-rows-in-a-matrix/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1463-the-k-weakest-rows-in-a-matrix/) | [Explanation](leetcode/1463-the-k-weakest-rows-in-a-matrix/Explanation.md) |
| 1340 | [Jump Game V](leetcode/1466-jump-game-v/) | Hard | [Dynamic Programming](patterns/dynamic-programming.md) | C++ | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/1466-jump-game-v/) | [Explanation](leetcode/1466-jump-game-v/Explanation.md) |
| 1341 | [Movie Rating](leetcode/1480-movie-rating/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1480-movie-rating/) | [Explanation](leetcode/1480-movie-rating/Explanation.md) |
| 1342 | [Number of Steps to Reduce a Number to Zero](leetcode/1444-number-of-steps-to-reduce-a-number-to-zero/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1444-number-of-steps-to-reduce-a-number-to-zero/) | [Explanation](leetcode/1444-number-of-steps-to-reduce-a-number-to-zero/Explanation.md) |
| 1344 | [Angle Between Hands of a Clock](leetcode/1446-angle-between-hands-of-a-clock/) | Medium | [Math & Logic](patterns/math-logic.md) | Java | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/1446-angle-between-hands-of-a-clock/) | [Explanation](leetcode/1446-angle-between-hands-of-a-clock/Explanation.md) |
| 1345 | [Jump Game IV](leetcode/1447-jump-game-iv/) | Hard | [Hash Map](patterns/hash-map.md) | C++ | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1447-jump-game-iv/) | [Explanation](leetcode/1447-jump-game-iv/Explanation.md) |
| 1346 | [Check If N and Its Double Exist](leetcode/1468-check-if-n-and-its-double-exist/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1468-check-if-n-and-its-double-exist/) | [Explanation](leetcode/1468-check-if-n-and-its-double-exist/Explanation.md) |
| 1351 | [Count Negative Numbers in a Sorted Matrix](leetcode/1476-count-negative-numbers-in-a-sorted-matrix/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1476-count-negative-numbers-in-a-sorted-matrix/) | [Explanation](leetcode/1476-count-negative-numbers-in-a-sorted-matrix/Explanation.md) |
| 1354 | [Construct Target Array With Multiple Sums](leetcode/1479-construct-target-array-with-multiple-sums/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1479-construct-target-array-with-multiple-sums/) | [Explanation](leetcode/1479-construct-target-array-with-multiple-sums/Explanation.md) |
| 1356 | [Sort Integers by The Number of 1 Bits](leetcode/1458-sort-integers-by-the-number-of-1-bits/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/1458-sort-integers-by-the-number-of-1-bits/) | [Explanation](leetcode/1458-sort-integers-by-the-number-of-1-bits/Explanation.md) |
| 1358 | [Number of Substrings Containing All Three Characters](leetcode/1460-number-of-substrings-containing-all-three-characters/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Java | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1460-number-of-substrings-containing-all-three-characters/) | [Explanation](leetcode/1460-number-of-substrings-containing-all-three-characters/Explanation.md) |
| 1360 | [Number of Days Between Two Dates](leetcode/1274-number-of-days-between-two-dates/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1274-number-of-days-between-two-dates/) | [Explanation](leetcode/1274-number-of-days-between-two-dates/Explanation.md) |
| 1365 | [How Many Numbers Are Smaller Than the Current Number](leetcode/1482-how-many-numbers-are-smaller-than-the-current-number/) | Easy | [Prefix Sum](patterns/prefix-sum.md) | TypeScript | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/1482-how-many-numbers-are-smaller-than-the-current-number/) | [Explanation](leetcode/1482-how-many-numbers-are-smaller-than-the-current-number/Explanation.md) |
| 1368 | [Minimum Cost to Make at Least One Valid Path in a Grid](leetcode/1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid/) | Hard | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid/) | [Explanation](leetcode/1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid/Explanation.md) |
| 1370 | [Increasing Decreasing String](leetcode/1472-increasing-decreasing-string/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1472-increasing-decreasing-string/) | [Explanation](leetcode/1472-increasing-decreasing-string/Explanation.md) |
| 1372 | [Longest ZigZag Path in a Binary Tree](leetcode/1474-longest-zigzag-path-in-a-binary-tree/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/1474-longest-zigzag-path-in-a-binary-tree/) | [Explanation](leetcode/1474-longest-zigzag-path-in-a-binary-tree/Explanation.md) |
| 1374 | [Generate a String With Characters That Have Odd Counts](leetcode/1490-generate-a-string-with-characters-that-have-odd-counts/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1490-generate-a-string-with-characters-that-have-odd-counts/) | [Explanation](leetcode/1490-generate-a-string-with-characters-that-have-odd-counts/Explanation.md) |
| 1378 | [Replace Employee ID With The Unique Identifier](leetcode/1509-replace-employee-id-with-the-unique-identifier/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1509-replace-employee-id-with-the-unique-identifier/) | [Explanation](leetcode/1509-replace-employee-id-with-the-unique-identifier/Explanation.md) |
| 1379 | [Find a Corresponding Node of a Binary Tree in a Clone of That Tree](leetcode/1498-find-a-corresponding-node-of-a-binary-tree-in-a-clone-of-that-tree/) | Easy | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/1498-find-a-corresponding-node-of-a-binary-tree-in-a-clone-of-that-tree/) | [Explanation](leetcode/1498-find-a-corresponding-node-of-a-binary-tree-in-a-clone-of-that-tree/Explanation.md) |
| 1380 | [Lucky Numbers in a Matrix](leetcode/1496-lucky-numbers-in-a-matrix/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1496-lucky-numbers-in-a-matrix/) | [Explanation](leetcode/1496-lucky-numbers-in-a-matrix/Explanation.md) |
| 1385 | [Find the Distance Value Between Two Arrays](leetcode/1486-find-the-distance-value-between-two-arrays/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1486-find-the-distance-value-between-two-arrays/) | [Explanation](leetcode/1486-find-the-distance-value-between-two-arrays/Explanation.md) |
| 1386 | [Cinema Seat Allocation](leetcode/1487-cinema-seat-allocation/) | Medium | [Hash Map](patterns/hash-map.md) | C++ | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1487-cinema-seat-allocation/) | [Explanation](leetcode/1487-cinema-seat-allocation/Explanation.md) |
| 1389 | [Create Target Array in the Given Order](leetcode/1505-create-target-array-in-the-given-order/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1505-create-target-array-in-the-given-order/) | [Explanation](leetcode/1505-create-target-array-in-the-given-order/Explanation.md) |
| 1392 | [Longest Happy Prefix](leetcode/1508-longest-happy-prefix/) | Hard | [Prefix Sum](patterns/prefix-sum.md) | Python | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/1508-longest-happy-prefix/) | [Explanation](leetcode/1508-longest-happy-prefix/Explanation.md) |
| 1393 | [Capital Gain/Loss](leetcode/1523-capital-gainloss/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1523-capital-gainloss/) | [Explanation](leetcode/1523-capital-gainloss/Explanation.md) |
| 1394 | [Find Lucky Integer in an Array](leetcode/1510-find-lucky-integer-in-an-array/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1510-find-lucky-integer-in-an-array/) | [Explanation](leetcode/1510-find-lucky-integer-in-an-array/Explanation.md) |
| 1395 | [Count Number of Teams](leetcode/1511-count-number-of-teams/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1511-count-number-of-teams/) | [Explanation](leetcode/1511-count-number-of-teams/Explanation.md) |
| 1399 | [Count Largest Group](leetcode/1500-count-largest-group/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1500-count-largest-group/) | [Explanation](leetcode/1500-count-largest-group/Explanation.md) |
| 1401 | [Circle and Rectangle Overlapping](leetcode/1501-circle-and-rectangle-overlapping/) | Medium | [Math & Logic](patterns/math-logic.md) | JavaScript | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/1501-circle-and-rectangle-overlapping/) | [Explanation](leetcode/1501-circle-and-rectangle-overlapping/Explanation.md) |
| 1403 | [Minimum Subsequence in Non-Increasing Order](leetcode/1519-minimum-subsequence-in-non-increasing-order/) | Easy | [Dynamic Programming](patterns/dynamic-programming.md) | Python | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/1519-minimum-subsequence-in-non-increasing-order/) | [Explanation](leetcode/1519-minimum-subsequence-in-non-increasing-order/Explanation.md) |
| 1406 | [Stone Game III](leetcode/1522-stone-game-iii/) | Hard | [Dynamic Programming](patterns/dynamic-programming.md) | PHP | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/1522-stone-game-iii/) | [Explanation](leetcode/1522-stone-game-iii/Explanation.md) |
| 1407 | [Top Travellers](leetcode/1541-top-travellers/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1541-top-travellers/) | [Explanation](leetcode/1541-top-travellers/Explanation.md) |
| 1408 | [String Matching in an Array](leetcode/1524-string-matching-in-an-array/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1524-string-matching-in-an-array/) | [Explanation](leetcode/1524-string-matching-in-an-array/Explanation.md) |
| 1409 | [Queries on a Permutation With Key](leetcode/1525-queries-on-a-permutation-with-key/) | Medium | [Backtracking](patterns/backtracking.md) | JavaScript | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/1525-queries-on-a-permutation-with-key/) | [Explanation](leetcode/1525-queries-on-a-permutation-with-key/Explanation.md) |
| 1413 | [Minimum Value to Get Positive Step by Step Sum](leetcode/1514-minimum-value-to-get-positive-step-by-step-sum/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1514-minimum-value-to-get-positive-step-by-step-sum/) | [Explanation](leetcode/1514-minimum-value-to-get-positive-step-by-step-sum/Explanation.md) |
| 1417 | [Reformat The String](leetcode/1532-reformat-the-string/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1532-reformat-the-string/) | [Explanation](leetcode/1532-reformat-the-string/Explanation.md) |
| 1422 | [Maximum Score After Splitting a String](leetcode/1537-maximum-score-after-splitting-a-string/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1537-maximum-score-after-splitting-a-string/) | [Explanation](leetcode/1537-maximum-score-after-splitting-a-string/Explanation.md) |
| 1431 | [Kids With the Greatest Number of Candies](leetcode/1528-kids-with-the-greatest-number-of-candies/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1528-kids-with-the-greatest-number-of-candies/) | [Explanation](leetcode/1528-kids-with-the-greatest-number-of-candies/Explanation.md) |
| 1436 | [Destination City](leetcode/1547-destination-city/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1547-destination-city/) | [Explanation](leetcode/1547-destination-city/Explanation.md) |
| 1437 | [Check If All 1's Are at Least Length K Places Away](leetcode/1548-check-if-all-1s-are-at-least-length-k-places-away/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1548-check-if-all-1s-are-at-least-length-k-places-away/) | [Explanation](leetcode/1548-check-if-all-1s-are-at-least-length-k-places-away/Explanation.md) |
| 1441 | [Build an Array With Stack Operations](leetcode/1552-build-an-array-with-stack-operations/) | Medium | [Stack & Queue](patterns/stack-queue.md) | TypeScript | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/1552-build-an-array-with-stack-operations/) | [Explanation](leetcode/1552-build-an-array-with-stack-operations/Explanation.md) |
| 1446 | [Consecutive Characters](leetcode/1542-consecutive-characters/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1542-consecutive-characters/) | [Explanation](leetcode/1542-consecutive-characters/Explanation.md) |
| 1447 | [Simplified Fractions](leetcode/1543-simplified-fractions/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1543-simplified-fractions/) | [Explanation](leetcode/1543-simplified-fractions/Explanation.md) |
| 1448 | [Count Good Nodes in Binary Tree](leetcode/1544-count-good-nodes-in-binary-tree/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/1544-count-good-nodes-in-binary-tree/) | [Explanation](leetcode/1544-count-good-nodes-in-binary-tree/Explanation.md) |
| 1450 | [Number of Students Doing Homework at a Given Time](leetcode/1560-number-of-students-doing-homework-at-a-given-time/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1560-number-of-students-doing-homework-at-a-given-time/) | [Explanation](leetcode/1560-number-of-students-doing-homework-at-a-given-time/Explanation.md) |
| 1455 | [Check If a Word Occurs As a Prefix of Any Word in a Sentence](leetcode/1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence/) | Easy | [Prefix Sum](patterns/prefix-sum.md) | Python | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence/) | [Explanation](leetcode/1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence/Explanation.md) |
| 1456 | [Maximum Number of Vowels in a Substring of Given Length](leetcode/1567-maximum-number-of-vowels-in-a-substring-of-given-length/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1567-maximum-number-of-vowels-in-a-substring-of-given-length/) | [Explanation](leetcode/1567-maximum-number-of-vowels-in-a-substring-of-given-length/Explanation.md) |
| 1460 | [Make Two Arrays Equal by Reversing Subarrays](leetcode/1556-make-two-arrays-equal-by-reversing-subarrays/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1556-make-two-arrays-equal-by-reversing-subarrays/) | [Explanation](leetcode/1556-make-two-arrays-equal-by-reversing-subarrays/Explanation.md) |
| 1461 | [Check If a String Contains All Binary Codes of Size K](leetcode/1557-check-if-a-string-contains-all-binary-codes-of-size-k/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/1557-check-if-a-string-contains-all-binary-codes-of-size-k/) | [Explanation](leetcode/1557-check-if-a-string-contains-all-binary-codes-of-size-k/Explanation.md) |
| 1464 | [Maximum Product of Two Elements in an Array](leetcode/1574-maximum-product-of-two-elements-in-an-array/) | Easy | [Binary Search](patterns/binary-search.md) | Scala | Modified Binary Search | O(n) | O(1) | [Code](leetcode/1574-maximum-product-of-two-elements-in-an-array/) | [Explanation](leetcode/1574-maximum-product-of-two-elements-in-an-array/Explanation.md) |
| 1466 | [Reorder Routes to Make All Paths Lead to the City Zero](leetcode/1576-reorder-routes-to-make-all-paths-lead-to-the-city-zero/) | Medium | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1576-reorder-routes-to-make-all-paths-lead-to-the-city-zero/) | [Explanation](leetcode/1576-reorder-routes-to-make-all-paths-lead-to-the-city-zero/Explanation.md) |
| 1470 | [Shuffle the Array](leetcode/1580-shuffle-the-array/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1580-shuffle-the-array/) | [Explanation](leetcode/1580-shuffle-the-array/Explanation.md) |
| 1475 | [Final Prices With a Special Discount in a Shop](leetcode/1570-final-prices-with-a-special-discount-in-a-shop/) | Easy | [Monotonic Stack](patterns/monotonic-stack.md) | TypeScript | Monotonic Stack Filtering | O(n) | O(n) | [Code](leetcode/1570-final-prices-with-a-special-discount-in-a-shop/) | [Explanation](leetcode/1570-final-prices-with-a-special-discount-in-a-shop/Explanation.md) |
| 1477 | [Find Two Non-overlapping Sub-arrays Each With Target Sum](leetcode/1573-find-two-non-overlapping-sub-arrays-each-with-target-sum/) | Medium | [Sliding Window](patterns/sliding-window.md) | JavaScript | Dynamic Sliding Window Traversal | O(n) | O(1) | [Code](leetcode/1573-find-two-non-overlapping-sub-arrays-each-with-target-sum/) | [Explanation](leetcode/1573-find-two-non-overlapping-sub-arrays-each-with-target-sum/Explanation.md) |
| 1480 | [Running Sum of 1d Array](leetcode/1603-running-sum-of-1d-array/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1603-running-sum-of-1d-array/) | [Explanation](leetcode/1603-running-sum-of-1d-array/Explanation.md) |
| 1483 | [Kth Ancestor of a Tree Node](leetcode/1296-kth-ancestor-of-a-tree-node/) | Hard | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/1296-kth-ancestor-of-a-tree-node/) | [Explanation](leetcode/1296-kth-ancestor-of-a-tree-node/Explanation.md) |
| 1484 | [Group Sold Products By The Date](leetcode/1625-group-sold-products-by-the-date/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1625-group-sold-products-by-the-date/) | [Explanation](leetcode/1625-group-sold-products-by-the-date/Explanation.md) |
| 1486 | [XOR Operation in an Array](leetcode/1610-xor-operation-in-an-array/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/1610-xor-operation-in-an-array/) | [Explanation](leetcode/1610-xor-operation-in-an-array/Explanation.md) |
| 1491 | [Average Salary Excluding the Minimum and Maximum Salary](leetcode/1584-average-salary-excluding-the-minimum-and-maximum-salary/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1584-average-salary-excluding-the-minimum-and-maximum-salary/) | [Explanation](leetcode/1584-average-salary-excluding-the-minimum-and-maximum-salary/Explanation.md) |
| 1493 | [Longest Subarray of 1's After Deleting One Element](leetcode/1586-longest-subarray-of-1s-after-deleting-one-element/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1586-longest-subarray-of-1s-after-deleting-one-element/) | [Explanation](leetcode/1586-longest-subarray-of-1s-after-deleting-one-element/Explanation.md) |
| 1496 | [Path Crossing](leetcode/1619-path-crossing/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1619-path-crossing/) | [Explanation](leetcode/1619-path-crossing/Explanation.md) |
| 1498 | [Number of Subsequences That Satisfy the Given Sum Condition](leetcode/1621-number-of-subsequences-that-satisfy-the-given-sum-condition/) | Medium | [Dynamic Programming](patterns/dynamic-programming.md) | JavaScript | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/1621-number-of-subsequences-that-satisfy-the-given-sum-condition/) | [Explanation](leetcode/1621-number-of-subsequences-that-satisfy-the-given-sum-condition/Explanation.md) |
| 1502 | [Can Make Arithmetic Progression From Sequence](leetcode/1626-can-make-arithmetic-progression-from-sequence/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1626-can-make-arithmetic-progression-from-sequence/) | [Explanation](leetcode/1626-can-make-arithmetic-progression-from-sequence/Explanation.md) |
| 1503 | [Last Moment Before All Ants Fall Out of a Plank](leetcode/1627-last-moment-before-all-ants-fall-out-of-a-plank/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1627-last-moment-before-all-ants-fall-out-of-a-plank/) | [Explanation](leetcode/1627-last-moment-before-all-ants-fall-out-of-a-plank/Explanation.md) |
| 1505 | [Minimum Possible Integer After at Most K Adjacent Swaps On Digits](leetcode/1629-minimum-possible-integer-after-at-most-k-adjacent-swaps-on-digits/) | Hard | [Math & Logic](patterns/math-logic.md) | JavaScript | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/1629-minimum-possible-integer-after-at-most-k-adjacent-swaps-on-digits/) | [Explanation](leetcode/1629-minimum-possible-integer-after-at-most-k-adjacent-swaps-on-digits/Explanation.md) |
| 1507 | [Reformat Date](leetcode/1283-reformat-date/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1283-reformat-date/) | [Explanation](leetcode/1283-reformat-date/Explanation.md) |
| 1510 | [Stone Game IV](leetcode/1617-stone-game-iv/) | Hard | [Dynamic Programming](patterns/dynamic-programming.md) | TypeScript | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/1617-stone-game-iv/) | [Explanation](leetcode/1617-stone-game-iv/Explanation.md) |
| 1512 | [Number of Good Pairs](leetcode/1635-number-of-good-pairs/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1635-number-of-good-pairs/) | [Explanation](leetcode/1635-number-of-good-pairs/Explanation.md) |
| 1514 | [Path with Maximum Probability](leetcode/1325-path-with-maximum-probability/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1325-path-with-maximum-probability/) | [Explanation](leetcode/1325-path-with-maximum-probability/Explanation.md) |
| 1517 | [Find Users With Valid E-Mails](leetcode/1664-find-users-with-valid-e-mails/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1664-find-users-with-valid-e-mails/) | [Explanation](leetcode/1664-find-users-with-valid-e-mails/Explanation.md) |
| 1518 | [Water Bottles](leetcode/1642-water-bottles/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1642-water-bottles/) | [Explanation](leetcode/1642-water-bottles/Explanation.md) |
| 1520 | [Maximum Number of Non-Overlapping Substrings](leetcode/1644-maximum-number-of-non-overlapping-substrings/) | Hard | [Heap](patterns/heap.md) | JavaScript | Min/Max Heap Priority Selection | O(n) | O(n) | [Code](leetcode/1644-maximum-number-of-non-overlapping-substrings/) | [Explanation](leetcode/1644-maximum-number-of-non-overlapping-substrings/Explanation.md) |
| 1523 | [Count Odd Numbers in an Interval Range](leetcode/1630-count-odd-numbers-in-an-interval-range/) | Easy | [Heap](patterns/heap.md) | Python | Min/Max Heap Priority Selection | O(n) | O(n) | [Code](leetcode/1630-count-odd-numbers-in-an-interval-range/) | [Explanation](leetcode/1630-count-odd-numbers-in-an-interval-range/Explanation.md) |
| 1527 | [Patients With a Condition](leetcode/1670-patients-with-a-condition/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1670-patients-with-a-condition/) | [Explanation](leetcode/1670-patients-with-a-condition/Explanation.md) |
| 1528 | [Shuffle String](leetcode/1651-shuffle-string/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1651-shuffle-string/) | [Explanation](leetcode/1651-shuffle-string/Explanation.md) |
| 1539 | [Kth Missing Positive Number](leetcode/1646-kth-missing-positive-number/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1646-kth-missing-positive-number/) | [Explanation](leetcode/1646-kth-missing-positive-number/Explanation.md) |
| 1541 | [Minimum Insertions to Balance a Parentheses String](leetcode/1648-minimum-insertions-to-balance-a-parentheses-string/) | Medium | [Stack & Queue](patterns/stack-queue.md) | Python | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/1648-minimum-insertions-to-balance-a-parentheses-string/) | [Explanation](leetcode/1648-minimum-insertions-to-balance-a-parentheses-string/Explanation.md) |
| 1544 | [Make The String Great](leetcode/1666-make-the-string-great/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1666-make-the-string-great/) | [Explanation](leetcode/1666-make-the-string-great/Explanation.md) |
| 1550 | [Three Consecutive Odds](leetcode/1293-three-consecutive-odds/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1293-three-consecutive-odds/) | [Explanation](leetcode/1293-three-consecutive-odds/Explanation.md) |
| 1556 | [Thousand Separator](leetcode/1660-thousand-separator/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1660-thousand-separator/) | [Explanation](leetcode/1660-thousand-separator/Explanation.md) |
| 1561 | [Maximum Number of Coins You Can Get](leetcode/1683-maximum-number-of-coins-you-can-get/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1683-maximum-number-of-coins-you-can-get/) | [Explanation](leetcode/1683-maximum-number-of-coins-you-can-get/Explanation.md) |
| 1563 | [Stone Game V](leetcode/1685-stone-game-v/) | Hard | [Prefix Sum](patterns/prefix-sum.md) | Java | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/1685-stone-game-v/) | [Explanation](leetcode/1685-stone-game-v/Explanation.md) |
| 1566 | [Detect Pattern of Length M Repeated K or More Times](leetcode/1689-detect-pattern-of-length-m-repeated-k-or-more-times/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1689-detect-pattern-of-length-m-repeated-k-or-more-times/) | [Explanation](leetcode/1689-detect-pattern-of-length-m-repeated-k-or-more-times/Explanation.md) |
| 1569 | [Number of Ways to Reorder Array to Get Same BST](leetcode/1692-number-of-ways-to-reorder-array-to-get-same-bst/) | Hard | [Binary Search](patterns/binary-search.md) | Python | Modified Binary Search | O(n) | O(1) | [Code](leetcode/1692-number-of-ways-to-reorder-array-to-get-same-bst/) | [Explanation](leetcode/1692-number-of-ways-to-reorder-array-to-get-same-bst/Explanation.md) |
| 1572 | [Matrix Diagonal Sum](leetcode/1677-matrix-diagonal-sum/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1677-matrix-diagonal-sum/) | [Explanation](leetcode/1677-matrix-diagonal-sum/Explanation.md) |
| 1581 | [Customer Who Visited but Did Not Make Any Transactions](leetcode/1724-customer-who-visited-but-did-not-make-any-transactions/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1724-customer-who-visited-but-did-not-make-any-transactions/) | [Explanation](leetcode/1724-customer-who-visited-but-did-not-make-any-transactions/Explanation.md) |
| 1587 | [Bank Account Summary II](leetcode/1734-bank-account-summary-ii/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1734-bank-account-summary-ii/) | [Explanation](leetcode/1734-bank-account-summary-ii/Explanation.md) |
| 1588 | [Sum of All Odd Length Subarrays](leetcode/1693-sum-of-all-odd-length-subarrays/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1693-sum-of-all-odd-length-subarrays/) | [Explanation](leetcode/1693-sum-of-all-odd-length-subarrays/Explanation.md) |
| 1590 | [Make Sum Divisible by P](leetcode/1694-make-sum-divisible-by-p/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1694-make-sum-divisible-by-p/) | [Explanation](leetcode/1694-make-sum-divisible-by-p/Explanation.md) |
| 1592 | [Rearrange Spaces Between Words](leetcode/1714-rearrange-spaces-between-words/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1714-rearrange-spaces-between-words/) | [Explanation](leetcode/1714-rearrange-spaces-between-words/Explanation.md) |
| 1598 | [Crawler Log Folder](leetcode/1720-crawler-log-folder/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1720-crawler-log-folder/) | [Explanation](leetcode/1720-crawler-log-folder/Explanation.md) |
| 1603 | [Design Parking System](leetcode/1708-design-parking-system/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1708-design-parking-system/) | [Explanation](leetcode/1708-design-parking-system/Explanation.md) |
| 1608 | [Special Array With X Elements Greater Than or Equal X](leetcode/1730-special-array-with-x-elements-greater-than-or-equal-x/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1730-special-array-with-x-elements-greater-than-or-equal-x/) | [Explanation](leetcode/1730-special-array-with-x-elements-greater-than-or-equal-x/Explanation.md) |
| 1614 | [Maximum Nesting Depth of the Parentheses](leetcode/1737-maximum-nesting-depth-of-the-parentheses/) | Easy | [Stack & Queue](patterns/stack-queue.md) | Java | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/1737-maximum-nesting-depth-of-the-parentheses/) | [Explanation](leetcode/1737-maximum-nesting-depth-of-the-parentheses/Explanation.md) |
| 1619 | [Mean of Array After Removing Some Elements](leetcode/1210-mean-of-array-after-removing-some-elements/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1210-mean-of-array-after-removing-some-elements/) | [Explanation](leetcode/1210-mean-of-array-after-removing-some-elements/Explanation.md) |
| 1621 | [Number of Sets of K Non-Overlapping Line Segments](leetcode/1725-number-of-sets-of-k-non-overlapping-line-segments/) | Medium | [Prefix Sum](patterns/prefix-sum.md) | JavaScript | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/1725-number-of-sets-of-k-non-overlapping-line-segments/) | [Explanation](leetcode/1725-number-of-sets-of-k-non-overlapping-line-segments/Explanation.md) |
| 1624 | [Largest Substring Between Two Equal Characters](leetcode/1746-largest-substring-between-two-equal-characters/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1746-largest-substring-between-two-equal-characters/) | [Explanation](leetcode/1746-largest-substring-between-two-equal-characters/Explanation.md) |
| 1629 | [Slowest Key](leetcode/1751-slowest-key/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1751-slowest-key/) | [Explanation](leetcode/1751-slowest-key/Explanation.md) |
| 1631 | [Path With Minimum Effort](leetcode/1753-path-with-minimum-effort/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1753-path-with-minimum-effort/) | [Explanation](leetcode/1753-path-with-minimum-effort/Explanation.md) |
| 1633 | [Percentage of Users Attended a Contest](leetcode/1773-percentage-of-users-attended-a-contest/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1773-percentage-of-users-attended-a-contest/) | [Explanation](leetcode/1773-percentage-of-users-attended-a-contest/Explanation.md) |
| 1636 | [Sort Array by Increasing Frequency](leetcode/1741-sort-array-by-increasing-frequency/) | Easy | [Hash Map](patterns/hash-map.md) | C++ | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1741-sort-array-by-increasing-frequency/) | [Explanation](leetcode/1741-sort-array-by-increasing-frequency/Explanation.md) |
| 1637 | [Widest Vertical Area Between Two Points Containing No Points](leetcode/1742-widest-vertical-area-between-two-points-containing-no-points/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1742-widest-vertical-area-between-two-points-containing-no-points/) | [Explanation](leetcode/1742-widest-vertical-area-between-two-points-containing-no-points/Explanation.md) |
| 1640 | [Check Array Formation Through Concatenation](leetcode/1760-check-array-formation-through-concatenation/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1760-check-array-formation-through-concatenation/) | [Explanation](leetcode/1760-check-array-formation-through-concatenation/Explanation.md) |
| 1646 | [Get Maximum in Generated Array](leetcode/1769-get-maximum-in-generated-array/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1769-get-maximum-in-generated-array/) | [Explanation](leetcode/1769-get-maximum-in-generated-array/Explanation.md) |
| 1649 | [Create Sorted Array through Instructions](leetcode/1772-create-sorted-array-through-instructions/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1772-create-sorted-array-through-instructions/) | [Explanation](leetcode/1772-create-sorted-array-through-instructions/Explanation.md) |
| 1652 | [Defuse the Bomb](leetcode/1755-defuse-the-bomb/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1755-defuse-the-bomb/) | [Explanation](leetcode/1755-defuse-the-bomb/Explanation.md) |
| 1656 | [Design an Ordered Stream](leetcode/1775-design-an-ordered-stream/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | C++ | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/1775-design-an-ordered-stream/) | [Explanation](leetcode/1775-design-an-ordered-stream/Explanation.md) |
| 1657 | [Determine if Two Strings Are Close](leetcode/1777-determine-if-two-strings-are-close/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1777-determine-if-two-strings-are-close/) | [Explanation](leetcode/1777-determine-if-two-strings-are-close/Explanation.md) |
| 1658 | [Minimum Operations to Reduce X to Zero](leetcode/1776-minimum-operations-to-reduce-x-to-zero/) | Medium | [Sliding Window](patterns/sliding-window.md) | JavaScript | Dynamic Sliding Window Traversal | O(n) | O(1) | [Code](leetcode/1776-minimum-operations-to-reduce-x-to-zero/) | [Explanation](leetcode/1776-minimum-operations-to-reduce-x-to-zero/Explanation.md) |
| 1661 | [Average Time of Process per Machine](leetcode/1801-average-time-of-process-per-machine/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1801-average-time-of-process-per-machine/) | [Explanation](leetcode/1801-average-time-of-process-per-machine/Explanation.md) |
| 1662 | [Check If Two String Arrays are Equivalent](leetcode/1781-check-if-two-string-arrays-are-equivalent/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1781-check-if-two-string-arrays-are-equivalent/) | [Explanation](leetcode/1781-check-if-two-string-arrays-are-equivalent/Explanation.md) |
| 1664 | [Ways to Make a Fair Array](leetcode/1783-ways-to-make-a-fair-array/) | Medium | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1783-ways-to-make-a-fair-array/) | [Explanation](leetcode/1783-ways-to-make-a-fair-array/Explanation.md) |
| 1665 | [Minimum Initial Energy to Finish Tasks](leetcode/1784-minimum-initial-energy-to-finish-tasks/) | Hard | [Binary Search](patterns/binary-search.md) | C++ | Modified Binary Search | O(log n) | O(1) | [Code](leetcode/1784-minimum-initial-energy-to-finish-tasks/) | [Explanation](leetcode/1784-minimum-initial-energy-to-finish-tasks/Explanation.md) |
| 1667 | [Fix Names in a Table](leetcode/1811-fix-names-in-a-table/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1811-fix-names-in-a-table/) | [Explanation](leetcode/1811-fix-names-in-a-table/Explanation.md) |
| 1668 | [Maximum Repeating Substring](leetcode/1764-maximum-repeating-substring/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1764-maximum-repeating-substring/) | [Explanation](leetcode/1764-maximum-repeating-substring/Explanation.md) |
| 1672 | [Richest Customer Wealth](leetcode/1791-richest-customer-wealth/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1791-richest-customer-wealth/) | [Explanation](leetcode/1791-richest-customer-wealth/Explanation.md) |
| 1674 | [Minimum Moves to Make Array Complementary](leetcode/1793-minimum-moves-to-make-array-complementary/) | Medium | [Hash Map](patterns/hash-map.md) | C++ | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1793-minimum-moves-to-make-array-complementary/) | [Explanation](leetcode/1793-minimum-moves-to-make-array-complementary/Explanation.md) |
| 1678 | [Goal Parser Interpretation](leetcode/1797-goal-parser-interpretation/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1797-goal-parser-interpretation/) | [Explanation](leetcode/1797-goal-parser-interpretation/Explanation.md) |
| 1679 | [Max Number of K-Sum Pairs](leetcode/1798-max-number-of-k-sum-pairs/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1798-max-number-of-k-sum-pairs/) | [Explanation](leetcode/1798-max-number-of-k-sum-pairs/Explanation.md) |
| 1682 | [Most Visited Sector In  A Circular Track](leetcode/1682-most-visited-sector-in--a-circular-track/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1682-most-visited-sector-in--a-circular-track/) | [Explanation](leetcode/1682-most-visited-sector-in--a-circular-track/Explanation.md) |
| 1683 | [Invalid Tweets](leetcode/1827-invalid-tweets/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1827-invalid-tweets/) | [Explanation](leetcode/1827-invalid-tweets/Explanation.md) |
| 1684 | [Count the Number of Consistent Strings](leetcode/1786-count-the-number-of-consistent-strings/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1786-count-the-number-of-consistent-strings/) | [Explanation](leetcode/1786-count-the-number-of-consistent-strings/Explanation.md) |
| 1686 | [Stone Game VI](leetcode/1788-stone-game-vi/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1788-stone-game-vi/) | [Explanation](leetcode/1788-stone-game-vi/Explanation.md) |
| 1688 | [Count of Matches in Tournament](leetcode/1806-count-of-matches-in-tournament/) | Easy | [Tree & Graph](patterns/tree-graph.md) | C++ | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1806-count-of-matches-in-tournament/) | [Explanation](leetcode/1806-count-of-matches-in-tournament/Explanation.md) |
| 1690 | [Stone Game VII](leetcode/1808-stone-game-vii/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1808-stone-game-vii/) | [Explanation](leetcode/1808-stone-game-vii/Explanation.md) |
| 1693 | [Daily Leads and Partners](leetcode/1837-daily-leads-and-partners/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1837-daily-leads-and-partners/) | [Explanation](leetcode/1837-daily-leads-and-partners/Explanation.md) |
| 1694 | [Reformat Phone Number](leetcode/1812-reformat-phone-number/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1812-reformat-phone-number/) | [Explanation](leetcode/1812-reformat-phone-number/Explanation.md) |
| 1700 | [Number of Students Unable to Eat Lunch](leetcode/1802-number-of-students-unable-to-eat-lunch/) | Easy | [Stack & Queue](patterns/stack-queue.md) | C++, JavaScript | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/1802-number-of-students-unable-to-eat-lunch/) | [Explanation](leetcode/1802-number-of-students-unable-to-eat-lunch/Explanation.md) |
| 1704 | [Determine if String Halves Are Alike](leetcode/1823-determine-if-string-halves-are-alike/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1823-determine-if-string-halves-are-alike/) | [Explanation](leetcode/1823-determine-if-string-halves-are-alike/Explanation.md) |
| 1710 | [Maximum Units on a Truck](leetcode/1829-maximum-units-on-a-truck/) | Easy | [Tree & Graph](patterns/tree-graph.md) | C++ | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1829-maximum-units-on-a-truck/) | [Explanation](leetcode/1829-maximum-units-on-a-truck/Explanation.md) |
| 1716 | [Calculate Money in Leetcode Bank](leetcode/1817-calculate-money-in-leetcode-bank/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1817-calculate-money-in-leetcode-bank/) | [Explanation](leetcode/1817-calculate-money-in-leetcode-bank/Explanation.md) |
| 1720 | [Decode XORed Array](leetcode/1839-decode-xored-array/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | C++ | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/1839-decode-xored-array/) | [Explanation](leetcode/1839-decode-xored-array/Explanation.md) |
| 1725 | [Number Of Rectangles That Can Form The Largest Square](leetcode/1843-number-of-rectangles-that-can-form-the-largest-square/) | Easy | [Math & Logic](patterns/math-logic.md) | C++ | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/1843-number-of-rectangles-that-can-form-the-largest-square/) | [Explanation](leetcode/1843-number-of-rectangles-that-can-form-the-largest-square/Explanation.md) |
| 1728 | [Cat and Mouse II](leetcode/1727-cat-and-mouse-ii/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1727-cat-and-mouse-ii/) | [Explanation](leetcode/1727-cat-and-mouse-ii/Explanation.md) |
| 1729 | [Find Followers Count](leetcode/1877-find-followers-count/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1877-find-followers-count/) | [Explanation](leetcode/1877-find-followers-count/Explanation.md) |
| 1731 | [The Number of Employees Which Report to Each Employee](leetcode/1882-the-number-of-employees-which-report-to-each-employee/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1882-the-number-of-employees-which-report-to-each-employee/) | [Explanation](leetcode/1882-the-number-of-employees-which-report-to-each-employee/Explanation.md) |
| 1732 | [Find the Highest Altitude](leetcode/1833-find-the-highest-altitude/) | Easy | [Array / General](patterns/array-general.md) | JavaScript, Kotlin, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1833-find-the-highest-altitude/) | [Explanation](leetcode/1833-find-the-highest-altitude/Explanation.md) |
| 1736 | [Latest Time by Replacing Hidden Digits](leetcode/1858-latest-time-by-replacing-hidden-digits/) | Easy | [Math & Logic](patterns/math-logic.md) | C++ | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/1858-latest-time-by-replacing-hidden-digits/) | [Explanation](leetcode/1858-latest-time-by-replacing-hidden-digits/Explanation.md) |
| 1741 | [Find Total Time Spent by Each Employee](leetcode/1892-find-total-time-spent-by-each-employee/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1892-find-total-time-spent-by-each-employee/) | [Explanation](leetcode/1892-find-total-time-spent-by-each-employee/Explanation.md) |
| 1742 | [Maximum Number of Balls in a Box](leetcode/1844-maximum-number-of-balls-in-a-box/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1844-maximum-number-of-balls-in-a-box/) | [Explanation](leetcode/1844-maximum-number-of-balls-in-a-box/Explanation.md) |
| 1748 | [Sum of Unique Elements](leetcode/1848-sum-of-unique-elements/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1848-sum-of-unique-elements/) | [Explanation](leetcode/1848-sum-of-unique-elements/Explanation.md) |
| 1752 | [Check if Array Is Sorted and Rotated](leetcode/1878-check-if-array-is-sorted-and-rotated/) | Easy | [Binary Search](patterns/binary-search.md) | C++ | Modified Binary Search | O(n) | O(1) | [Code](leetcode/1878-check-if-array-is-sorted-and-rotated/) | [Explanation](leetcode/1878-check-if-array-is-sorted-and-rotated/Explanation.md) |
| 1757 | [Recyclable and Low Fat Products](leetcode/1908-recyclable-and-low-fat-products/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1908-recyclable-and-low-fat-products/) | [Explanation](leetcode/1908-recyclable-and-low-fat-products/Explanation.md) |
| 1758 | [Minimum Changes To Make Alternating Binary String](leetcode/1884-minimum-changes-to-make-alternating-binary-string/) | Easy | [Tree & Graph](patterns/tree-graph.md) | C++ | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1884-minimum-changes-to-make-alternating-binary-string/) | [Explanation](leetcode/1884-minimum-changes-to-make-alternating-binary-string/Explanation.md) |
| 1763 | [Longest Nice Substring](leetcode/1873-longest-nice-substring/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1873-longest-nice-substring/) | [Explanation](leetcode/1873-longest-nice-substring/Explanation.md) |
| 1768 | [Merge Strings Alternately](leetcode/1894-merge-strings-alternately/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1894-merge-strings-alternately/) | [Explanation](leetcode/1894-merge-strings-alternately/Explanation.md) |
| 1773 | [Count Items Matching a Rule](leetcode/1899-count-items-matching-a-rule/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1899-count-items-matching-a-rule/) | [Explanation](leetcode/1899-count-items-matching-a-rule/Explanation.md) |
| 1779 | [Find Nearest Point That Has the Same X or Y Coordinate](leetcode/1888-find-nearest-point-that-has-the-same-x-or-y-coordinate/) | Easy | [Tree & Graph](patterns/tree-graph.md) | C++ | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1888-find-nearest-point-that-has-the-same-x-or-y-coordinate/) | [Explanation](leetcode/1888-find-nearest-point-that-has-the-same-x-or-y-coordinate/Explanation.md) |
| 1784 | [Check if Binary String Has at Most One Segment of Ones](leetcode/1910-check-if-binary-string-has-at-most-one-segment-of-ones/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | C++ | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/1910-check-if-binary-string-has-at-most-one-segment-of-ones/) | [Explanation](leetcode/1910-check-if-binary-string-has-at-most-one-segment-of-ones/Explanation.md) |
| 1786 | [Number of Restricted Paths From First to Last Node](leetcode/1912-number-of-restricted-paths-from-first-to-last-node/) | Medium | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/1912-number-of-restricted-paths-from-first-to-last-node/) | [Explanation](leetcode/1912-number-of-restricted-paths-from-first-to-last-node/Explanation.md) |
| 1789 | [Primary Department for Each Employee](leetcode/1942-primary-department-for-each-employee/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1942-primary-department-for-each-employee/) | [Explanation](leetcode/1942-primary-department-for-each-employee/Explanation.md) |
| 1790 | [Check if One String Swap Can Make Strings Equal](leetcode/1915-check-if-one-string-swap-can-make-strings-equal/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1915-check-if-one-string-swap-can-make-strings-equal/) | [Explanation](leetcode/1915-check-if-one-string-swap-can-make-strings-equal/Explanation.md) |
| 1791 | [Find Center of Star Graph](leetcode/1916-find-center-of-star-graph/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1916-find-center-of-star-graph/) | [Explanation](leetcode/1916-find-center-of-star-graph/Explanation.md) |
| 1795 | [Rearrange Products Table](leetcode/1948-rearrange-products-table/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/1948-rearrange-products-table/) | [Explanation](leetcode/1948-rearrange-products-table/Explanation.md) |
| 1796 | [Second Largest Digit in a String](leetcode/1904-second-largest-digit-in-a-string/) | Easy | [Math & Logic](patterns/math-logic.md) | C++ | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/1904-second-largest-digit-in-a-string/) | [Explanation](leetcode/1904-second-largest-digit-in-a-string/Explanation.md) |
| 1800 | [Maximum Ascending Subarray Sum](leetcode/1927-maximum-ascending-subarray-sum/) | Easy | [Two Pointers](patterns/two-pointers.md) | C++ | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/1927-maximum-ascending-subarray-sum/) | [Explanation](leetcode/1927-maximum-ascending-subarray-sum/Explanation.md) |
| 1805 | [Number of Different Integers in a String](leetcode/1933-number-of-different-integers-in-a-string/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | C++ | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/1933-number-of-different-integers-in-a-string/) | [Explanation](leetcode/1933-number-of-different-integers-in-a-string/Explanation.md) |
| 1807 | [Evaluate the Bracket Pairs of a String](leetcode/1934-evaluate-the-bracket-pairs-of-a-string/) | Medium | [Hash Map](patterns/hash-map.md) | C++ | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1934-evaluate-the-bracket-pairs-of-a-string/) | [Explanation](leetcode/1934-evaluate-the-bracket-pairs-of-a-string/Explanation.md) |
| 1812 | [Determine Color of a Chessboard Square](leetcode/1920-determine-color-of-a-chessboard-square/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1920-determine-color-of-a-chessboard-square/) | [Explanation](leetcode/1920-determine-color-of-a-chessboard-square/Explanation.md) |
| 1816 | [Truncate Sentence](leetcode/1944-truncate-sentence/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1944-truncate-sentence/) | [Explanation](leetcode/1944-truncate-sentence/Explanation.md) |
| 1819 | [Number of Different Subsequences GCDs](leetcode/1947-number-of-different-subsequences-gcds/) | Hard | [Dynamic Programming](patterns/dynamic-programming.md) | Python | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/1947-number-of-different-subsequences-gcds/) | [Explanation](leetcode/1947-number-of-different-subsequences-gcds/Explanation.md) |
| 1822 | [Sign of the Product of an Array](leetcode/1950-sign-of-the-product-of-an-array/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1950-sign-of-the-product-of-an-array/) | [Explanation](leetcode/1950-sign-of-the-product-of-an-array/Explanation.md) |
| 1827 | [Minimum Operations to Make the Array Increasing](leetcode/1938-minimum-operations-to-make-the-array-increasing/) | Easy | [Hash Map](patterns/hash-map.md) | C++ | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/1938-minimum-operations-to-make-the-array-increasing/) | [Explanation](leetcode/1938-minimum-operations-to-make-the-array-increasing/Explanation.md) |
| 1832 | [Check if the Sentence Is Pangram](leetcode/1960-check-if-the-sentence-is-pangram/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1960-check-if-the-sentence-is-pangram/) | [Explanation](leetcode/1960-check-if-the-sentence-is-pangram/Explanation.md) |
| 1833 | [Maximum Ice Cream Bars](leetcode/1961-maximum-ice-cream-bars/) | Medium | [Binary Search](patterns/binary-search.md) | Java | Modified Binary Search | O(n) | O(1) | [Code](leetcode/1961-maximum-ice-cream-bars/) | [Explanation](leetcode/1961-maximum-ice-cream-bars/Explanation.md) |
| 1837 | [Sum of Digits in Base K](leetcode/1965-sum-of-digits-in-base-k/) | Easy | [Math & Logic](patterns/math-logic.md) | C++ | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/1965-sum-of-digits-in-base-k/) | [Explanation](leetcode/1965-sum-of-digits-in-base-k/Explanation.md) |
| 1840 | [Maximum Building Height](leetcode/1968-maximum-building-height/) | Hard | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1968-maximum-building-height/) | [Explanation](leetcode/1968-maximum-building-height/Explanation.md) |
| 1844 | [Replace All Digits with Characters](leetcode/1954-replace-all-digits-with-characters/) | Easy | [Math & Logic](patterns/math-logic.md) | C++ | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/1954-replace-all-digits-with-characters/) | [Explanation](leetcode/1954-replace-all-digits-with-characters/Explanation.md) |
| 1846 | [Maximum Element After Decreasing and Rearranging](leetcode/1956-maximum-element-after-decreasing-and-rearranging/) | Medium | [Binary Search](patterns/binary-search.md) | Java | Modified Binary Search | O(log n) | O(1) | [Code](leetcode/1956-maximum-element-after-decreasing-and-rearranging/) | [Explanation](leetcode/1956-maximum-element-after-decreasing-and-rearranging/Explanation.md) |
| 1848 | [Minimum Distance to the Target Element](leetcode/1975-minimum-distance-to-the-target-element/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1975-minimum-distance-to-the-target-element/) | [Explanation](leetcode/1975-minimum-distance-to-the-target-element/Explanation.md) |
| 1851 | [Minimum Interval to Include Each Query](leetcode/1977-minimum-interval-to-include-each-query/) | Hard | [Heap](patterns/heap.md) | Python | Min/Max Heap Priority Selection | O(n) | O(n) | [Code](leetcode/1977-minimum-interval-to-include-each-query/) | [Explanation](leetcode/1977-minimum-interval-to-include-each-query/Explanation.md) |
| 1854 | [Maximum Population Year](leetcode/1983-maximum-population-year/) | Easy | [Tree & Graph](patterns/tree-graph.md) | C++ | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/1983-maximum-population-year/) | [Explanation](leetcode/1983-maximum-population-year/Explanation.md) |
| 1859 | [Sorting the Sentence](leetcode/1970-sorting-the-sentence/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1970-sorting-the-sentence/) | [Explanation](leetcode/1970-sorting-the-sentence/Explanation.md) |
| 1861 | [Rotating the Box](leetcode/1972-rotating-the-box/) | Medium | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1972-rotating-the-box/) | [Explanation](leetcode/1972-rotating-the-box/Explanation.md) |
| 1863 | [Sum of All Subset XOR Totals](leetcode/1993-sum-of-all-subset-xor-totals/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | C++ | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/1993-sum-of-all-subset-xor-totals/) | [Explanation](leetcode/1993-sum-of-all-subset-xor-totals/Explanation.md) |
| 1866 | [Number of Ways to Rearrange Sticks With K Sticks Visible](leetcode/1996-number-of-ways-to-rearrange-sticks-with-k-sticks-visible/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1996-number-of-ways-to-rearrange-sticks-with-k-sticks-visible/) | [Explanation](leetcode/1996-number-of-ways-to-rearrange-sticks-with-k-sticks-visible/Explanation.md) |
| 1869 | [Longer Contiguous Segments of Ones than Zeros](leetcode/1999-longer-contiguous-segments-of-ones-than-zeros/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1999-longer-contiguous-segments-of-ones-than-zeros/) | [Explanation](leetcode/1999-longer-contiguous-segments-of-ones-than-zeros/Explanation.md) |
| 1871 | [Jump Game VII](leetcode/2001-jump-game-vii/) | Medium | [Prefix Sum](patterns/prefix-sum.md) | C++ | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/2001-jump-game-vii/) | [Explanation](leetcode/2001-jump-game-vii/Explanation.md) |
| 1872 | [Stone Game VIII](leetcode/2002-stone-game-viii/) | Hard | [Prefix Sum](patterns/prefix-sum.md) | Java | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/2002-stone-game-viii/) | [Explanation](leetcode/2002-stone-game-viii/Explanation.md) |
| 1873 | [Calculate Special Bonus](leetcode/2024-calculate-special-bonus/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/2024-calculate-special-bonus/) | [Explanation](leetcode/2024-calculate-special-bonus/Explanation.md) |
| 1876 | [Substrings of Size Three with Distinct Characters](leetcode/1987-substrings-of-size-three-with-distinct-characters/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1987-substrings-of-size-three-with-distinct-characters/) | [Explanation](leetcode/1987-substrings-of-size-three-with-distinct-characters/Explanation.md) |
| 1880 | [Check if Word Equals Summation of Two Words](leetcode/2010-check-if-word-equals-summation-of-two-words/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2010-check-if-word-equals-summation-of-two-words/) | [Explanation](leetcode/2010-check-if-word-equals-summation-of-two-words/Explanation.md) |
| 1886 | [Determine Whether Matrix Can Be Obtained By Rotation](leetcode/2015-determine-whether-matrix-can-be-obtained-by-rotation/) | Easy | [Tree & Graph](patterns/tree-graph.md) | C++ | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/2015-determine-whether-matrix-can-be-obtained-by-rotation/) | [Explanation](leetcode/2015-determine-whether-matrix-can-be-obtained-by-rotation/Explanation.md) |
| 1887 | [Reduction Operations to Make the Array Elements Equal](leetcode/2016-reduction-operations-to-make-the-array-elements-equal/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2016-reduction-operations-to-make-the-array-elements-equal/) | [Explanation](leetcode/2016-reduction-operations-to-make-the-array-elements-equal/Explanation.md) |
| 1890 | [The Latest Login in 2020](leetcode/2041-the-latest-login-in-2020/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/2041-the-latest-login-in-2020/) | [Explanation](leetcode/2041-the-latest-login-in-2020/Explanation.md) |
| 1893 | [Check if All the Integers in a Range Are Covered](leetcode/2005-check-if-all-the-integers-in-a-range-are-covered/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2005-check-if-all-the-integers-in-a-range-are-covered/) | [Explanation](leetcode/2005-check-if-all-the-integers-in-a-range-are-covered/Explanation.md) |
| 1897 | [Redistribute Characters to Make All Strings Equal](leetcode/2025-redistribute-characters-to-make-all-strings-equal/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2025-redistribute-characters-to-make-all-strings-equal/) | [Explanation](leetcode/2025-redistribute-characters-to-make-all-strings-equal/Explanation.md) |
| 1903 | [Largest Odd Number in String](leetcode/2032-largest-odd-number-in-string/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2032-largest-odd-number-in-string/) | [Explanation](leetcode/2032-largest-odd-number-in-string/Explanation.md) |
| 1907 | [Count Salary Categories](leetcode/2057-count-salary-categories/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/2057-count-salary-categories/) | [Explanation](leetcode/2057-count-salary-categories/Explanation.md) |
| 1909 | [Remove One Element to Make the Array Strictly Increasing](leetcode/2020-remove-one-element-to-make-the-array-strictly-increasing/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2020-remove-one-element-to-make-the-array-strictly-increasing/) | [Explanation](leetcode/2020-remove-one-element-to-make-the-array-strictly-increasing/Explanation.md) |
| 1913 | [Maximum Product Difference Between Two Pairs](leetcode/2042-maximum-product-difference-between-two-pairs/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2042-maximum-product-difference-between-two-pairs/) | [Explanation](leetcode/2042-maximum-product-difference-between-two-pairs/Explanation.md) |
| 1914 | [Cyclically Rotating a Grid](leetcode/2043-cyclically-rotating-a-grid/) | Medium | [Tree & Graph](patterns/tree-graph.md) | C++ | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/2043-cyclically-rotating-a-grid/) | [Explanation](leetcode/2043-cyclically-rotating-a-grid/Explanation.md) |
| 1920 | [Build Array from Permutation](leetcode/2048-build-array-from-permutation/) | Easy | [Backtracking](patterns/backtracking.md) | C++ | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/2048-build-array-from-permutation/) | [Explanation](leetcode/2048-build-array-from-permutation/Explanation.md) |
| 1923 | [Longest Common Subpath](leetcode/2051-longest-common-subpath/) | Hard | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/2051-longest-common-subpath/) | [Explanation](leetcode/2051-longest-common-subpath/Explanation.md) |
| 1925 | [Count Square Sum Triples](leetcode/2037-count-square-sum-triples/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2037-count-square-sum-triples/) | [Explanation](leetcode/2037-count-square-sum-triples/Explanation.md) |
| 1926 | [Nearest Exit from Entrance in Maze](leetcode/2038-nearest-exit-from-entrance-in-maze/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2038-nearest-exit-from-entrance-in-maze/) | [Explanation](leetcode/2038-nearest-exit-from-entrance-in-maze/Explanation.md) |
| 1927 | [Sum Game](leetcode/2039-sum-game/) | Medium | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2039-sum-game/) | [Explanation](leetcode/2039-sum-game/Explanation.md) |
| 1928 | [Minimum Cost to Reach Destination in Time](leetcode/2040-minimum-cost-to-reach-destination-in-time/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2040-minimum-cost-to-reach-destination-in-time/) | [Explanation](leetcode/2040-minimum-cost-to-reach-destination-in-time/Explanation.md) |
| 1929 | [Concatenation of Array](leetcode/2058-concatenation-of-array/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2058-concatenation-of-array/) | [Explanation](leetcode/2058-concatenation-of-array/Explanation.md) |
| 1934 | [Confirmation Rate](leetcode/2087-confirmation-rate/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/2087-confirmation-rate/) | [Explanation](leetcode/2087-confirmation-rate/Explanation.md) |
| 1935 | [Maximum Number of Words You Can Type](leetcode/1264-maximum-number-of-words-you-can-type/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1264-maximum-number-of-words-you-can-type/) | [Explanation](leetcode/1264-maximum-number-of-words-you-can-type/Explanation.md) |
| 1941 | [Check if All Characters Have Equal Number of Occurrences](leetcode/2053-check-if-all-characters-have-equal-number-of-occurrences/) | Easy | [Hash Map](patterns/hash-map.md) | C++ | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/2053-check-if-all-characters-have-equal-number-of-occurrences/) | [Explanation](leetcode/2053-check-if-all-characters-have-equal-number-of-occurrences/Explanation.md) |
| 1945 | [Sum of Digits of String After Convert](leetcode/2076-sum-of-digits-of-string-after-convert/) | Easy | [Math & Logic](patterns/math-logic.md) | C++ | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/2076-sum-of-digits-of-string-after-convert/) | [Explanation](leetcode/2076-sum-of-digits-of-string-after-convert/Explanation.md) |
| 1952 | [Three Divisors](leetcode/2083-three-divisors/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2083-three-divisors/) | [Explanation](leetcode/2083-three-divisors/Explanation.md) |
| 1957 | [Delete Characters to Make Fancy String](leetcode/1302-delete-characters-to-make-fancy-string/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1302-delete-characters-to-make-fancy-string/) | [Explanation](leetcode/1302-delete-characters-to-make-fancy-string/Explanation.md) |
| 1961 | [Check If String Is a Prefix of Array](leetcode/2093-check-if-string-is-a-prefix-of-array/) | Easy | [Prefix Sum](patterns/prefix-sum.md) | C++ | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/2093-check-if-string-is-a-prefix-of-array/) | [Explanation](leetcode/2093-check-if-string-is-a-prefix-of-array/Explanation.md) |
| 1964 | [Find the Longest Valid Obstacle Course at Each Position](leetcode/2096-find-the-longest-valid-obstacle-course-at-each-position/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2096-find-the-longest-valid-obstacle-course-at-each-position/) | [Explanation](leetcode/2096-find-the-longest-valid-obstacle-course-at-each-position/Explanation.md) |
| 1965 | [Employees With Missing Information](leetcode/2110-employees-with-missing-information/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/2110-employees-with-missing-information/) | [Explanation](leetcode/2110-employees-with-missing-information/Explanation.md) |
| 1967 | [Number of Strings That Appear as Substrings in Word](leetcode/2099-number-of-strings-that-appear-as-substrings-in-word/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Kotlin | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/2099-number-of-strings-that-appear-as-substrings-in-word/) | [Explanation](leetcode/2099-number-of-strings-that-appear-as-substrings-in-word/Explanation.md) |
| 1971 | [Find if Path Exists in Graph](leetcode/2121-find-if-path-exists-in-graph/) | Easy | [Dynamic Programming](patterns/dynamic-programming.md) | JavaScript | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/2121-find-if-path-exists-in-graph/) | [Explanation](leetcode/2121-find-if-path-exists-in-graph/Explanation.md) |
| 1974 | [Minimum Time to Type Word Using Special Typewriter](leetcode/2088-minimum-time-to-type-word-using-special-typewriter/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2088-minimum-time-to-type-word-using-special-typewriter/) | [Explanation](leetcode/2088-minimum-time-to-type-word-using-special-typewriter/Explanation.md) |
| 1976 | [Number of Ways to Arrive at Destination](leetcode/2090-number-of-ways-to-arrive-at-destination/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2090-number-of-ways-to-arrive-at-destination/) | [Explanation](leetcode/2090-number-of-ways-to-arrive-at-destination/Explanation.md) |
| 1978 | [Employees Whose Manager Left the Company](leetcode/2127-employees-whose-manager-left-the-company/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/2127-employees-whose-manager-left-the-company/) | [Explanation](leetcode/2127-employees-whose-manager-left-the-company/Explanation.md) |
| 1979 | [Find Greatest Common Divisor of Array](leetcode/2106-find-greatest-common-divisor-of-array/) | Easy | [Array / General](patterns/array-general.md) | Kotlin | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2106-find-greatest-common-divisor-of-array/) | [Explanation](leetcode/2106-find-greatest-common-divisor-of-array/Explanation.md) |
| 1984 | [Minimum Difference Between Highest and Lowest of K Scores](leetcode/2112-minimum-difference-between-highest-and-lowest-of-k-scores/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2112-minimum-difference-between-highest-and-lowest-of-k-scores/) | [Explanation](leetcode/2112-minimum-difference-between-highest-and-lowest-of-k-scores/Explanation.md) |
| 1991 | [Find the Middle Index in Array](leetcode/2102-find-the-middle-index-in-array/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2102-find-the-middle-index-in-array/) | [Explanation](leetcode/2102-find-the-middle-index-in-array/Explanation.md) |
| 1995 | [Count Special Quadruplets](leetcode/2122-count-special-quadruplets/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2122-count-special-quadruplets/) | [Explanation](leetcode/2122-count-special-quadruplets/Explanation.md) |
| 1998 | [GCD Sort of an Array](leetcode/2125-gcd-sort-of-an-array/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2125-gcd-sort-of-an-array/) | [Explanation](leetcode/2125-gcd-sort-of-an-array/Explanation.md) |
| 2000 | [Reverse Prefix of Word](leetcode/2128-reverse-prefix-of-word/) | Easy | [Prefix Sum](patterns/prefix-sum.md) | JavaScript | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/2128-reverse-prefix-of-word/) | [Explanation](leetcode/2128-reverse-prefix-of-word/Explanation.md) |
| 2011 | [Final Value of Variable After Performing Operations](leetcode/2137-final-value-of-variable-after-performing-operations/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2137-final-value-of-variable-after-performing-operations/) | [Explanation](leetcode/2137-final-value-of-variable-after-performing-operations/Explanation.md) |
| 2027 | [Minimum Moves to Convert String](leetcode/2154-minimum-moves-to-convert-string/) | Easy | [Hash Map](patterns/hash-map.md) | JavaScript | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/2154-minimum-moves-to-convert-string/) | [Explanation](leetcode/2154-minimum-moves-to-convert-string/Explanation.md) |
| 2029 | [Stone Game IX](leetcode/2156-stone-game-ix/) | Medium | [Tree & Graph](patterns/tree-graph.md) | C++ | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/2156-stone-game-ix/) | [Explanation](leetcode/2156-stone-game-ix/Explanation.md) |
| 2037 | [Minimum Number of Moves to Seat Everyone](leetcode/2148-minimum-number-of-moves-to-seat-everyone/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2148-minimum-number-of-moves-to-seat-everyone/) | [Explanation](leetcode/2148-minimum-number-of-moves-to-seat-everyone/Explanation.md) |
| 2038 | [Remove Colored Pieces if Both Neighbors are the Same Color](leetcode/2149-remove-colored-pieces-if-both-neighbors-are-the-same-color/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2149-remove-colored-pieces-if-both-neighbors-are-the-same-color/) | [Explanation](leetcode/2149-remove-colored-pieces-if-both-neighbors-are-the-same-color/Explanation.md) |
| 2042 | [Check if Numbers Are Ascending in a Sentence](leetcode/2168-check-if-numbers-are-ascending-in-a-sentence/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2168-check-if-numbers-are-ascending-in-a-sentence/) | [Explanation](leetcode/2168-check-if-numbers-are-ascending-in-a-sentence/Explanation.md) |
| 2045 | [Second Minimum Time to Reach Destination](leetcode/2171-second-minimum-time-to-reach-destination/) | Hard | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/2171-second-minimum-time-to-reach-destination/) | [Explanation](leetcode/2171-second-minimum-time-to-reach-destination/Explanation.md) |
| 2047 | [Number of Valid Words in a Sentence](leetcode/2173-number-of-valid-words-in-a-sentence/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2173-number-of-valid-words-in-a-sentence/) | [Explanation](leetcode/2173-number-of-valid-words-in-a-sentence/Explanation.md) |
| 2053 | [Kth Distinct String in an Array](leetcode/2163-kth-distinct-string-in-an-array/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2163-kth-distinct-string-in-an-array/) | [Explanation](leetcode/2163-kth-distinct-string-in-an-array/Explanation.md) |
| 2058 | [Find the Minimum and Maximum Number of Nodes Between Critical Points](leetcode/2182-find-the-minimum-and-maximum-number-of-nodes-between-critical-points/) | Medium | [Two Pointers](patterns/two-pointers.md) | C++ | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/2182-find-the-minimum-and-maximum-number-of-nodes-between-critical-points/) | [Explanation](leetcode/2182-find-the-minimum-and-maximum-number-of-nodes-between-critical-points/Explanation.md) |
| 2062 | [Count Vowel Substrings of a String](leetcode/2186-count-vowel-substrings-of-a-string/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2186-count-vowel-substrings-of-a-string/) | [Explanation](leetcode/2186-count-vowel-substrings-of-a-string/Explanation.md) |
| 2068 | [Check Whether Two Strings are Almost Equivalent](leetcode/2177-check-whether-two-strings-are-almost-equivalent/) | Easy | [Hash Map](patterns/hash-map.md) | JavaScript | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/2177-check-whether-two-strings-are-almost-equivalent/) | [Explanation](leetcode/2177-check-whether-two-strings-are-almost-equivalent/Explanation.md) |
| 2073 | [Time Needed to Buy Tickets](leetcode/2195-time-needed-to-buy-tickets/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2195-time-needed-to-buy-tickets/) | [Explanation](leetcode/2195-time-needed-to-buy-tickets/Explanation.md) |
| 2085 | [Count Common Words With One Occurrence](leetcode/2190-count-common-words-with-one-occurrence/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2190-count-common-words-with-one-occurrence/) | [Explanation](leetcode/2190-count-common-words-with-one-occurrence/Explanation.md) |
| 2089 | [Find Target Indices After Sorting Array](leetcode/2210-find-target-indices-after-sorting-array/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2210-find-target-indices-after-sorting-array/) | [Explanation](leetcode/2210-find-target-indices-after-sorting-array/Explanation.md) |
| 2091 | [Removing Minimum and Maximum From Array](leetcode/2212-removing-minimum-and-maximum-from-array/) | Medium | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2212-removing-minimum-and-maximum-from-array/) | [Explanation](leetcode/2212-removing-minimum-and-maximum-from-array/Explanation.md) |
| 2094 | [Finding 3-Digit Even Numbers](leetcode/2215-finding-3-digit-even-numbers/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/2215-finding-3-digit-even-numbers/) | [Explanation](leetcode/2215-finding-3-digit-even-numbers/Explanation.md) |
| 2095 | [Delete the Middle Node of a Linked List](leetcode/2216-delete-the-middle-node-of-a-linked-list/) | Medium | [Fast & Slow Pointers](patterns/fast-slow-pointers.md) | Java, JavaScript | Floyd Cycle Detection | O(n) | O(1) | [Code](leetcode/2216-delete-the-middle-node-of-a-linked-list/) | [Explanation](leetcode/2216-delete-the-middle-node-of-a-linked-list/Explanation.md) |
| 2096 | [Step-By-Step Directions From a Binary Tree Node to Another](leetcode/2217-step-by-step-directions-from-a-binary-tree-node-to-another/) | Medium | [Two Pointers](patterns/two-pointers.md) | JavaScript | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/2217-step-by-step-directions-from-a-binary-tree-node-to-another/) | [Explanation](leetcode/2217-step-by-step-directions-from-a-binary-tree-node-to-another/Explanation.md) |
| 2099 | [Find Subsequence of Length K With the Largest Sum](leetcode/2204-find-subsequence-of-length-k-with-the-largest-sum/) | Easy | [Dynamic Programming](patterns/dynamic-programming.md) | Python | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/2204-find-subsequence-of-length-k-with-the-largest-sum/) | [Explanation](leetcode/2204-find-subsequence-of-length-k-with-the-largest-sum/Explanation.md) |
| 2103 | [Rings and Rods](leetcode/2226-rings-and-rods/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2226-rings-and-rods/) | [Explanation](leetcode/2226-rings-and-rods/Explanation.md) |
| 2108 | [Find First Palindromic String in the Array](leetcode/2231-find-first-palindromic-string-in-the-array/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2231-find-first-palindromic-string-in-the-array/) | [Explanation](leetcode/2231-find-first-palindromic-string-in-the-array/Explanation.md) |
| 2109 | [Adding Spaces to a String](leetcode/2232-adding-spaces-to-a-string/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2232-adding-spaces-to-a-string/) | [Explanation](leetcode/2232-adding-spaces-to-a-string/Explanation.md) |
| 2114 | [Maximum Number of Words Found in Sentences](leetcode/2219-maximum-number-of-words-found-in-sentences/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2219-maximum-number-of-words-found-in-sentences/) | [Explanation](leetcode/2219-maximum-number-of-words-found-in-sentences/Explanation.md) |
| 2119 | [A Number After a Double Reversal](leetcode/2238-a-number-after-a-double-reversal/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2238-a-number-after-a-double-reversal/) | [Explanation](leetcode/2238-a-number-after-a-double-reversal/Explanation.md) |
| 2126 | [Destroying Asteroids](leetcode/2245-destroying-asteroids/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | Java | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/2245-destroying-asteroids/) | [Explanation](leetcode/2245-destroying-asteroids/Explanation.md) |
| 2130 | [Maximum Twin Sum of a Linked List](leetcode/2236-maximum-twin-sum-of-a-linked-list/) | Medium | [Fast & Slow Pointers](patterns/fast-slow-pointers.md) | Java, JavaScript | Floyd Cycle Detection | O(n) | O(1) | [Code](leetcode/2236-maximum-twin-sum-of-a-linked-list/) | [Explanation](leetcode/2236-maximum-twin-sum-of-a-linked-list/Explanation.md) |
| 2144 | [Minimum Cost of Buying Candies With Discount](leetcode/2248-minimum-cost-of-buying-candies-with-discount/) | Easy | [Sliding Window](patterns/sliding-window.md) | Kotlin | Dynamic Sliding Window Traversal | O(n) | O(1) | [Code](leetcode/2248-minimum-cost-of-buying-candies-with-discount/) | [Explanation](leetcode/2248-minimum-cost-of-buying-candies-with-discount/Explanation.md) |
| 2161 | [Partition Array According to Given Pivot](leetcode/2265-partition-array-according-to-given-pivot/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Java | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/2265-partition-array-according-to-given-pivot/) | [Explanation](leetcode/2265-partition-array-according-to-given-pivot/Explanation.md) |
| 2179 | [Count Good Triplets in an Array](leetcode/2280-count-good-triplets-in-an-array/) | Hard | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/2280-count-good-triplets-in-an-array/) | [Explanation](leetcode/2280-count-good-triplets-in-an-array/Explanation.md) |
| 2183 | [Count Array Pairs Divisible by K](leetcode/2301-count-array-pairs-divisible-by-k/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2301-count-array-pairs-divisible-by-k/) | [Explanation](leetcode/2301-count-array-pairs-divisible-by-k/Explanation.md) |
| 2193 | [Minimum Number of Moves to Make Palindrome](leetcode/1356-minimum-number-of-moves-to-make-palindrome/) | Hard | [Two Pointers](patterns/two-pointers.md) | JavaScript | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/1356-minimum-number-of-moves-to-make-palindrome/) | [Explanation](leetcode/1356-minimum-number-of-moves-to-make-palindrome/Explanation.md) |
| 2196 | [Create Binary Tree From Descriptions](leetcode/2306-create-binary-tree-from-descriptions/) | Medium | [Binary Search](patterns/binary-search.md) | Java | Modified Binary Search | O(n) | O(1) | [Code](leetcode/2306-create-binary-tree-from-descriptions/) | [Explanation](leetcode/2306-create-binary-tree-from-descriptions/Explanation.md) |
| 2197 | [Replace Non-Coprime Numbers in Array](leetcode/2307-replace-non-coprime-numbers-in-array/) | Hard | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/2307-replace-non-coprime-numbers-in-array/) | [Explanation](leetcode/2307-replace-non-coprime-numbers-in-array/Explanation.md) |
| 2213 | [Longest Substring of One Repeating Character](leetcode/2319-longest-substring-of-one-repeating-character/) | Hard | [Binary Search](patterns/binary-search.md) | Java | Modified Binary Search | O(n) | O(1) | [Code](leetcode/2319-longest-substring-of-one-repeating-character/) | [Explanation](leetcode/2319-longest-substring-of-one-repeating-character/Explanation.md) |
| 2215 | [Find the Difference of Two Arrays](leetcode/1392-find-the-difference-of-two-arrays/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/1392-find-the-difference-of-two-arrays/) | [Explanation](leetcode/1392-find-the-difference-of-two-arrays/Explanation.md) |
| 2250 | [Count Number of Rectangles Containing Each Point](leetcode/2333-count-number-of-rectangles-containing-each-point/) | Medium | [Math & Logic](patterns/math-logic.md) | JavaScript | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/2333-count-number-of-rectangles-containing-each-point/) | [Explanation](leetcode/2333-count-number-of-rectangles-containing-each-point/Explanation.md) |
| 2265 | [Count Nodes Equal to Average of Subtree](leetcode/2347-count-nodes-equal-to-average-of-subtree/) | Medium | [Two Pointers](patterns/two-pointers.md) | JavaScript | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/2347-count-nodes-equal-to-average-of-subtree/) | [Explanation](leetcode/2347-count-nodes-equal-to-average-of-subtree/Explanation.md) |
| 2267 | [ Check if There Is a Valid Parentheses String Path](leetcode/2349--check-if-there-is-a-valid-parentheses-string-path/) | Hard | [Stack & Queue](patterns/stack-queue.md) | C++ | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/2349--check-if-there-is-a-valid-parentheses-string-path/) | [Explanation](leetcode/2349--check-if-there-is-a-valid-parentheses-string-path/Explanation.md) |
| 2267 | [ Check if There Is a Valid Parentheses String Path](leetcode/2349-check-if-there-is-a-valid-parentheses-string-path/) | Hard | [Stack & Queue](patterns/stack-queue.md) | C++ | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/2349-check-if-there-is-a-valid-parentheses-string-path/) | [Explanation](leetcode/2349-check-if-there-is-a-valid-parentheses-string-path/Explanation.md) |
| 2286 | [Booking Concert Tickets in Groups](leetcode/2380-booking-concert-tickets-in-groups/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2380-booking-concert-tickets-in-groups/) | [Explanation](leetcode/2380-booking-concert-tickets-in-groups/Explanation.md) |
| 2290 | [Minimum Obstacle Removal to Reach Corner](leetcode/2375-minimum-obstacle-removal-to-reach-corner/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2375-minimum-obstacle-removal-to-reach-corner/) | [Explanation](leetcode/2375-minimum-obstacle-removal-to-reach-corner/Explanation.md) |
| 2300 | [Successful Pairs of Spells and Potions](leetcode/2392-successful-pairs-of-spells-and-potions/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2392-successful-pairs-of-spells-and-potions/) | [Explanation](leetcode/2392-successful-pairs-of-spells-and-potions/Explanation.md) |
| 2333 | [Minimum Sum of Squared Difference](leetcode/2418-minimum-sum-of-squared-difference/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2418-minimum-sum-of-squared-difference/) | [Explanation](leetcode/2418-minimum-sum-of-squared-difference/Explanation.md) |
| 2336 | [Smallest Number in Infinite Set](leetcode/2413-smallest-number-in-infinite-set/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | JavaScript | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/2413-smallest-number-in-infinite-set/) | [Explanation](leetcode/2413-smallest-number-in-infinite-set/Explanation.md) |
| 2344 | [Minimum Deletions to Make Array Divisible](leetcode/2423-minimum-deletions-to-make-array-divisible/) | Hard | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/2423-minimum-deletions-to-make-array-divisible/) | [Explanation](leetcode/2423-minimum-deletions-to-make-array-divisible/Explanation.md) |
| 2352 | [Equal Row and Column Pairs](leetcode/2428-equal-row-and-column-pairs/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2428-equal-row-and-column-pairs/) | [Explanation](leetcode/2428-equal-row-and-column-pairs/Explanation.md) |
| 2356 | [Number of Unique Subjects Taught by Each Teacher](leetcode/2495-number-of-unique-subjects-taught-by-each-teacher/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/2495-number-of-unique-subjects-taught-by-each-teacher/) | [Explanation](leetcode/2495-number-of-unique-subjects-taught-by-each-teacher/Explanation.md) |
| 2390 | [Removing Stars From a String](leetcode/2470-removing-stars-from-a-string/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2470-removing-stars-from-a-string/) | [Explanation](leetcode/2470-removing-stars-from-a-string/Explanation.md) |
| 2396 | [Strictly Palindromic Number](leetcode/2481-strictly-palindromic-number/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2481-strictly-palindromic-number/) | [Explanation](leetcode/2481-strictly-palindromic-number/Explanation.md) |
| 2407 | [Longest Increasing Subsequence II](leetcode/2526-longest-increasing-subsequence-ii/) | Hard | [Dynamic Programming](patterns/dynamic-programming.md) | JavaScript | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/2526-longest-increasing-subsequence-ii/) | [Explanation](leetcode/2526-longest-increasing-subsequence-ii/Explanation.md) |
| 2419 | [Longest Subarray With Maximum Bitwise AND](leetcode/2503-longest-subarray-with-maximum-bitwise-and/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/2503-longest-subarray-with-maximum-bitwise-and/) | [Explanation](leetcode/2503-longest-subarray-with-maximum-bitwise-and/Explanation.md) |
| 2424 | [Longest Uploaded Prefix](leetcode/2512-longest-uploaded-prefix/) | Medium | [Prefix Sum](patterns/prefix-sum.md) | JavaScript | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/2512-longest-uploaded-prefix/) | [Explanation](leetcode/2512-longest-uploaded-prefix/Explanation.md) |
| 2425 | [Bitwise XOR of All Pairings](leetcode/2533-bitwise-xor-of-all-pairings/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/2533-bitwise-xor-of-all-pairings/) | [Explanation](leetcode/2533-bitwise-xor-of-all-pairings/Explanation.md) |
| 2426 | [Number of Pairs Satisfying Inequality](leetcode/2513-number-of-pairs-satisfying-inequality/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2513-number-of-pairs-satisfying-inequality/) | [Explanation](leetcode/2513-number-of-pairs-satisfying-inequality/Explanation.md) |
| 2427 | [Number of Common Factors](leetcode/2507-number-of-common-factors/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2507-number-of-common-factors/) | [Explanation](leetcode/2507-number-of-common-factors/Explanation.md) |
| 2462 | [Total Cost to Hire K Workers](leetcode/2553-total-cost-to-hire-k-workers/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2553-total-cost-to-hire-k-workers/) | [Explanation](leetcode/2553-total-cost-to-hire-k-workers/Explanation.md) |
| 2472 | [Maximum Number of Non-overlapping Palindrome Substrings](leetcode/2559-maximum-number-of-non-overlapping-palindrome-substrings/) | Hard | [Two Pointers](patterns/two-pointers.md) | JavaScript | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/2559-maximum-number-of-non-overlapping-palindrome-substrings/) | [Explanation](leetcode/2559-maximum-number-of-non-overlapping-palindrome-substrings/Explanation.md) |
| 2485 | [Find the Pivot Integer](leetcode/2571-find-the-pivot-integer/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2571-find-the-pivot-integer/) | [Explanation](leetcode/2571-find-the-pivot-integer/Explanation.md) |
| 2492 | [Minimum Score of a Path Between Two Cities](leetcode/2582-minimum-score-of-a-path-between-two-cities/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Java | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/2582-minimum-score-of-a-path-between-two-cities/) | [Explanation](leetcode/2582-minimum-score-of-a-path-between-two-cities/Explanation.md) |
| 2507 | [Smallest Value After Replacing With Sum of Prime Factors](leetcode/2595-smallest-value-after-replacing-with-sum-of-prime-factors/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2595-smallest-value-after-replacing-with-sum-of-prime-factors/) | [Explanation](leetcode/2595-smallest-value-after-replacing-with-sum-of-prime-factors/Explanation.md) |
| 2509 | [Cycle Length Queries in a Tree](leetcode/2597-cycle-length-queries-in-a-tree/) | Hard | [Fast & Slow Pointers](patterns/fast-slow-pointers.md) | JavaScript | Floyd Cycle Detection | O(n) | O(1) | [Code](leetcode/2597-cycle-length-queries-in-a-tree/) | [Explanation](leetcode/2597-cycle-length-queries-in-a-tree/Explanation.md) |
| 2513 | [Minimize the Maximum of Two Arrays](leetcode/2628-minimize-the-maximum-of-two-arrays/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2628-minimize-the-maximum-of-two-arrays/) | [Explanation](leetcode/2628-minimize-the-maximum-of-two-arrays/Explanation.md) |
| 2521 | [Distinct Prime Factors of Product of Array](leetcode/2609-distinct-prime-factors-of-product-of-array/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2609-distinct-prime-factors-of-product-of-array/) | [Explanation](leetcode/2609-distinct-prime-factors-of-product-of-array/Explanation.md) |
| 2523 | [Closest Prime Numbers in Range](leetcode/2610-closest-prime-numbers-in-range/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | JavaScript, Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/2610-closest-prime-numbers-in-range/) | [Explanation](leetcode/2610-closest-prime-numbers-in-range/Explanation.md) |
| 2540 | [Minimum Common Value](leetcode/2634-minimum-common-value/) | Easy | [Sliding Window](patterns/sliding-window.md) | C++ | Dynamic Sliding Window Traversal | O(n) | O(1) | [Code](leetcode/2634-minimum-common-value/) | [Explanation](leetcode/2634-minimum-common-value/Explanation.md) |
| 2542 | [Maximum Subsequence Score](leetcode/2636-maximum-subsequence-score/) | Medium | [Dynamic Programming](patterns/dynamic-programming.md) | JavaScript | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/2636-maximum-subsequence-score/) | [Explanation](leetcode/2636-maximum-subsequence-score/Explanation.md) |
| 2543 | [Check if Point Is Reachable](leetcode/2635-check-if-point-is-reachable/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2635-check-if-point-is-reachable/) | [Explanation](leetcode/2635-check-if-point-is-reachable/Explanation.md) |
| 2552 | [Count Increasing Quadruplets](leetcode/2682-count-increasing-quadruplets/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2682-count-increasing-quadruplets/) | [Explanation](leetcode/2682-count-increasing-quadruplets/Explanation.md) |
| 2553 | [Separate the Digits in an Array](leetcode/2639-separate-the-digits-in-an-array/) | Easy | [Math & Logic](patterns/math-logic.md) | C++ | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/2639-separate-the-digits-in-an-array/) | [Explanation](leetcode/2639-separate-the-digits-in-an-array/Explanation.md) |
| 2568 | [Minimum Impossible OR](leetcode/2705-minimum-impossible-or/) | Medium | [Sliding Window](patterns/sliding-window.md) | Python | Dynamic Sliding Window Traversal | O(n) | O(1) | [Code](leetcode/2705-minimum-impossible-or/) | [Explanation](leetcode/2705-minimum-impossible-or/Explanation.md) |
| 2574 | [Left and Right Sum Differences](leetcode/2714-left-and-right-sum-differences/) | Easy | [Prefix Sum](patterns/prefix-sum.md) | Kotlin | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/2714-left-and-right-sum-differences/) | [Explanation](leetcode/2714-left-and-right-sum-differences/Explanation.md) |
| 2618 | [Check if Object Instance of Class](leetcode/2758-check-if-object-instance-of-class/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2758-check-if-object-instance-of-class/) | [Explanation](leetcode/2758-check-if-object-instance-of-class/Explanation.md) |
| 2619 | [Array Prototype Last](leetcode/2734-array-prototype-last/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2734-array-prototype-last/) | [Explanation](leetcode/2734-array-prototype-last/Explanation.md) |
| 2620 | [Counter](leetcode/2732-counter/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2732-counter/) | [Explanation](leetcode/2732-counter/Explanation.md) |
| 2621 | [Sleep](leetcode/2733-sleep/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2733-sleep/) | [Explanation](leetcode/2733-sleep/Explanation.md) |
| 2622 | [Cache With Time Limit](leetcode/2762-cache-with-time-limit/) | Medium | [Hash Map](patterns/hash-map.md) | JavaScript | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/2762-cache-with-time-limit/) | [Explanation](leetcode/2762-cache-with-time-limit/Explanation.md) |
| 2623 | [Memoize](leetcode/2731-memoize/) | Medium | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2731-memoize/) | [Explanation](leetcode/2731-memoize/Explanation.md) |
| 2624 | [Snail Traversal](leetcode/2760-snail-traversal/) | Medium | [Tree & Graph](patterns/tree-graph.md) | TypeScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/2760-snail-traversal/) | [Explanation](leetcode/2760-snail-traversal/Explanation.md) |
| 2625 | [Flatten Deeply Nested Array](leetcode/2759-flatten-deeply-nested-array/) | Medium | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2759-flatten-deeply-nested-array/) | [Explanation](leetcode/2759-flatten-deeply-nested-array/Explanation.md) |
| 2626 | [Array Reduce Transformation](leetcode/2761-array-reduce-transformation/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2761-array-reduce-transformation/) | [Explanation](leetcode/2761-array-reduce-transformation/Explanation.md) |
| 2627 | [Debounce](leetcode/2743-debounce/) | Medium | [Sliding Window](patterns/sliding-window.md) | TypeScript | Dynamic Sliding Window Traversal | O(n) | O(1) | [Code](leetcode/2743-debounce/) | [Explanation](leetcode/2743-debounce/Explanation.md) |
| 2629 | [Function Composition](leetcode/2741-function-composition/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2741-function-composition/) | [Explanation](leetcode/2741-function-composition/Explanation.md) |
| 2630 | [Memoize II](leetcode/2744-memoize-ii/) | Hard | [Hash Map](patterns/hash-map.md) | TypeScript | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/2744-memoize-ii/) | [Explanation](leetcode/2744-memoize-ii/Explanation.md) |
| 2631 | [Group By](leetcode/2742-group-by/) | Medium | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2742-group-by/) | [Explanation](leetcode/2742-group-by/Explanation.md) |
| 2634 | [Filter Elements from Array](leetcode/2746-filter-elements-from-array/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2746-filter-elements-from-array/) | [Explanation](leetcode/2746-filter-elements-from-array/Explanation.md) |
| 2635 | [Apply Transform Over Each Element in Array](leetcode/2747-apply-transform-over-each-element-in-array/) | Easy | [Hash Map](patterns/hash-map.md) | TypeScript | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/2747-apply-transform-over-each-element-in-array/) | [Explanation](leetcode/2747-apply-transform-over-each-element-in-array/Explanation.md) |
| 2637 | [Promise Time Limit](leetcode/2749-promise-time-limit/) | Medium | [Math & Logic](patterns/math-logic.md) | TypeScript | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/2749-promise-time-limit/) | [Explanation](leetcode/2749-promise-time-limit/Explanation.md) |
| 2648 | [Generate Fibonacci Sequence](leetcode/2775-generate-fibonacci-sequence/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2775-generate-fibonacci-sequence/) | [Explanation](leetcode/2775-generate-fibonacci-sequence/Explanation.md) |
| 2649 | [Nested Array Generator](leetcode/2783-nested-array-generator/) | Medium | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2783-nested-array-generator/) | [Explanation](leetcode/2783-nested-array-generator/Explanation.md) |
| 2650 | [Design Cancellable Function](leetcode/2788-design-cancellable-function/) | Hard | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2788-design-cancellable-function/) | [Explanation](leetcode/2788-design-cancellable-function/Explanation.md) |
| 2654 | [Minimum Number of Operations to Make All Array Elements Equal to 1](leetcode/2753-minimum-number-of-operations-to-make-all-array-elements-equal-to-1/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2753-minimum-number-of-operations-to-make-all-array-elements-equal-to-1/) | [Explanation](leetcode/2753-minimum-number-of-operations-to-make-all-array-elements-equal-to-1/Explanation.md) |
| 2657 | [Find the Prefix Common Array of Two Arrays](leetcode/2766-find-the-prefix-common-array-of-two-arrays/) | Medium | [Prefix Sum](patterns/prefix-sum.md) | C++ | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/2766-find-the-prefix-common-array-of-two-arrays/) | [Explanation](leetcode/2766-find-the-prefix-common-array-of-two-arrays/Explanation.md) |
| 2659 | [Make Array Empty](leetcode/2765-make-array-empty/) | Hard | [Hash Map](patterns/hash-map.md) | JavaScript | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/2765-make-array-empty/) | [Explanation](leetcode/2765-make-array-empty/Explanation.md) |
| 2665 | [Counter II](leetcode/2789-counter-ii/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2789-counter-ii/) | [Explanation](leetcode/2789-counter-ii/Explanation.md) |
| 2666 | [Allow One Function Call](leetcode/2796-allow-one-function-call/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2796-allow-one-function-call/) | [Explanation](leetcode/2796-allow-one-function-call/Explanation.md) |
| 2667 | [Create Hello World Function](leetcode/2809-create-hello-world-function/) | Easy | [Tree & Graph](patterns/tree-graph.md) | TypeScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/2809-create-hello-world-function/) | [Explanation](leetcode/2809-create-hello-world-function/Explanation.md) |
| 2677 | [Chunk Array](leetcode/2798-chunk-array/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2798-chunk-array/) | [Explanation](leetcode/2798-chunk-array/Explanation.md) |
| 2685 | [Count the Number of Complete Components](leetcode/2793-count-the-number-of-complete-components/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Java | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/2793-count-the-number-of-complete-components/) | [Explanation](leetcode/2793-count-the-number-of-complete-components/Explanation.md) |
| 2693 | [Call Function with Custom Context](leetcode/2790-call-function-with-custom-context/) | Medium | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2790-call-function-with-custom-context/) | [Explanation](leetcode/2790-call-function-with-custom-context/Explanation.md) |
| 2694 | [Event Emitter](leetcode/2797-event-emitter/) | Medium | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2797-event-emitter/) | [Explanation](leetcode/2797-event-emitter/Explanation.md) |
| 2695 | [Array Wrapper](leetcode/2805-array-wrapper/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2805-array-wrapper/) | [Explanation](leetcode/2805-array-wrapper/Explanation.md) |
| 2703 | [Return Length of Arguments Passed](leetcode/2820-return-length-of-arguments-passed/) | Easy | [Hash Map](patterns/hash-map.md) | TypeScript | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/2820-return-length-of-arguments-passed/) | [Explanation](leetcode/2820-return-length-of-arguments-passed/Explanation.md) |
| 2704 | [To Be Or Not To Be](leetcode/2813-to-be-or-not-to-be/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2813-to-be-or-not-to-be/) | [Explanation](leetcode/2813-to-be-or-not-to-be/Explanation.md) |
| 2705 | [Compact Object](leetcode/2804-compact-object/) | Medium | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2804-compact-object/) | [Explanation](leetcode/2804-compact-object/Explanation.md) |
| 2709 | [Greatest Common Divisor Traversal](leetcode/2827-greatest-common-divisor-traversal/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2827-greatest-common-divisor-traversal/) | [Explanation](leetcode/2827-greatest-common-divisor-traversal/Explanation.md) |
| 2721 | [Execute Asynchronous Functions in Parallel](leetcode/2807-execute-asynchronous-functions-in-parallel/) | Medium | [Two Pointers](patterns/two-pointers.md) | TypeScript | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/2807-execute-asynchronous-functions-in-parallel/) | [Explanation](leetcode/2807-execute-asynchronous-functions-in-parallel/Explanation.md) |
| 2722 | [Join Two Arrays by ID](leetcode/2858-join-two-arrays-by-id/) | Medium | [Hash Map](patterns/hash-map.md) | TypeScript | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/2858-join-two-arrays-by-id/) | [Explanation](leetcode/2858-join-two-arrays-by-id/Explanation.md) |
| 2723 | [Add Two Promises](leetcode/2859-add-two-promises/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | TypeScript | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/2859-add-two-promises/) | [Explanation](leetcode/2859-add-two-promises/Explanation.md) |
| 2724 | [Sort By](leetcode/2860-sort-by/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2860-sort-by/) | [Explanation](leetcode/2860-sort-by/Explanation.md) |
| 2725 | [Interval Cancellation](leetcode/2862-interval-cancellation/) | Easy | [Heap](patterns/heap.md) | TypeScript | Min/Max Heap Priority Selection | O(n) | O(n) | [Code](leetcode/2862-interval-cancellation/) | [Explanation](leetcode/2862-interval-cancellation/Explanation.md) |
| 2726 | [Calculator with Method Chaining](leetcode/2863-calculator-with-method-chaining/) | Easy | [Hash Map](patterns/hash-map.md) | TypeScript | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/2863-calculator-with-method-chaining/) | [Explanation](leetcode/2863-calculator-with-method-chaining/Explanation.md) |
| 2727 | [Is Object Empty](leetcode/2864-is-object-empty/) | Easy | [Array / General](patterns/array-general.md) | TypeScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2864-is-object-empty/) | [Explanation](leetcode/2864-is-object-empty/Explanation.md) |
| 2731 | [Movement of Robots](leetcode/2787-movement-of-robots/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2787-movement-of-robots/) | [Explanation](leetcode/2787-movement-of-robots/Explanation.md) |
| 2736 | [Maximum Sum Queries](leetcode/2839-maximum-sum-queries/) | Hard | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/2839-maximum-sum-queries/) | [Explanation](leetcode/2839-maximum-sum-queries/Explanation.md) |
| 2745 | [Construct the Longest New String](leetcode/2850-construct-the-longest-new-string/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2850-construct-the-longest-new-string/) | [Explanation](leetcode/2850-construct-the-longest-new-string/Explanation.md) |
| 2749 | [Minimum Operations to Make the Integer Zero](leetcode/2837-minimum-operations-to-make-the-integer-zero/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2837-minimum-operations-to-make-the-integer-zero/) | [Explanation](leetcode/2837-minimum-operations-to-make-the-integer-zero/Explanation.md) |
| 2770 | [Maximum Number of Jumps to Reach the Last Index](leetcode/2855-maximum-number-of-jumps-to-reach-the-last-index/) | Medium | [Dynamic Programming](patterns/dynamic-programming.md) | C++ | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/2855-maximum-number-of-jumps-to-reach-the-last-index/) | [Explanation](leetcode/2855-maximum-number-of-jumps-to-reach-the-last-index/Explanation.md) |
| 2778 | [Sum of Squares of Special Elements ](leetcode/2844-sum-of-squares-of-special-elements-/) | Easy | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2844-sum-of-squares-of-special-elements-/) | [Explanation](leetcode/2844-sum-of-squares-of-special-elements-/Explanation.md) |
| 2784 | [Check if Array is Good](leetcode/2892-check-if-array-is-good/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/2892-check-if-array-is-good/) | [Explanation](leetcode/2892-check-if-array-is-good/Explanation.md) |
| 2812 | [Find the Safest Path in a Grid](leetcode/2914-find-the-safest-path-in-a-grid/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Java | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/2914-find-the-safest-path-in-a-grid/) | [Explanation](leetcode/2914-find-the-safest-path-in-a-grid/Explanation.md) |
| 2867 | [Count Valid Paths in a Tree](leetcode/3112-count-valid-paths-in-a-tree/) | Hard | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3112-count-valid-paths-in-a-tree/) | [Explanation](leetcode/3112-count-valid-paths-in-a-tree/Explanation.md) |
| 2877 | [Create a DataFrame from List](leetcode/3062-create-a-dataframe-from-list/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/3062-create-a-dataframe-from-list/) | [Explanation](leetcode/3062-create-a-dataframe-from-list/Explanation.md) |
| 2878 | [Get the Size of a DataFrame](leetcode/3076-get-the-size-of-a-dataframe/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/3076-get-the-size-of-a-dataframe/) | [Explanation](leetcode/3076-get-the-size-of-a-dataframe/Explanation.md) |
| 2879 | [Display the First Three Rows](leetcode/3065-display-the-first-three-rows/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3065-display-the-first-three-rows/) | [Explanation](leetcode/3065-display-the-first-three-rows/Explanation.md) |
| 2880 | [Select Data](leetcode/3074-select-data/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/3074-select-data/) | [Explanation](leetcode/3074-select-data/Explanation.md) |
| 2881 | [Create a New Column](leetcode/3066-create-a-new-column/) | Easy | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/3066-create-a-new-column/) | [Explanation](leetcode/3066-create-a-new-column/Explanation.md) |
| 2882 | [Drop Duplicate Rows](leetcode/3071-drop-duplicate-rows/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3071-drop-duplicate-rows/) | [Explanation](leetcode/3071-drop-duplicate-rows/Explanation.md) |
| 2883 | [Drop Missing Data](leetcode/3075-drop-missing-data/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/3075-drop-missing-data/) | [Explanation](leetcode/3075-drop-missing-data/Explanation.md) |
| 2884 | [Modify Columns](leetcode/3067-modify-columns/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3067-modify-columns/) | [Explanation](leetcode/3067-modify-columns/Explanation.md) |
| 2885 | [Rename Columns](leetcode/3068-rename-columns/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3068-rename-columns/) | [Explanation](leetcode/3068-rename-columns/Explanation.md) |
| 2886 | [Change Data Type](leetcode/3069-change-data-type/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/3069-change-data-type/) | [Explanation](leetcode/3069-change-data-type/Explanation.md) |
| 2887 | [Fill Missing Data](leetcode/3070-fill-missing-data/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/3070-fill-missing-data/) | [Explanation](leetcode/3070-fill-missing-data/Explanation.md) |
| 2888 | [Reshape Data: Concatenate](leetcode/3064-reshape-data-concatenate/) | Easy | [Stack & Queue](patterns/stack-queue.md) | Python | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/3064-reshape-data-concatenate/) | [Explanation](leetcode/3064-reshape-data-concatenate/Explanation.md) |
| 2889 | [Reshape Data: Pivot](leetcode/3072-reshape-data-pivot/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3072-reshape-data-pivot/) | [Explanation](leetcode/3072-reshape-data-pivot/Explanation.md) |
| 2890 | [Reshape Data: Melt](leetcode/3073-reshape-data-melt/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/3073-reshape-data-melt/) | [Explanation](leetcode/3073-reshape-data-melt/Explanation.md) |
| 2891 | [Method Chaining](leetcode/3063-method-chaining/) | Easy | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/3063-method-chaining/) | [Explanation](leetcode/3063-method-chaining/Explanation.md) |
| 2897 | [Apply Operations on Array to Maximize Sum of Squares](leetcode/3153-apply-operations-on-array-to-maximize-sum-of-squares/) | Hard | [Stack & Queue](patterns/stack-queue.md) | JavaScript | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/3153-apply-operations-on-array-to-maximize-sum-of-squares/) | [Explanation](leetcode/3153-apply-operations-on-array-to-maximize-sum-of-squares/Explanation.md) |
| 2904 | [Shortest and Lexicographically Smallest Beautiful String](leetcode/3150-shortest-and-lexicographically-smallest-beautiful-string/) | Medium | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3150-shortest-and-lexicographically-smallest-beautiful-string/) | [Explanation](leetcode/3150-shortest-and-lexicographically-smallest-beautiful-string/Explanation.md) |
| 2913 | [Subarrays Distinct Element Sum of Squares I](leetcode/3163-subarrays-distinct-element-sum-of-squares-i/) | Easy | [Monotonic Stack](patterns/monotonic-stack.md) | JavaScript | Monotonic Stack Filtering | O(n) | O(n) | [Code](leetcode/3163-subarrays-distinct-element-sum-of-squares-i/) | [Explanation](leetcode/3163-subarrays-distinct-element-sum-of-squares-i/Explanation.md) |
| 2916 | [Subarrays Distinct Element Sum of Squares II](leetcode/3139-subarrays-distinct-element-sum-of-squares-ii/) | Hard | [Array / General](patterns/array-general.md) | JavaScript, Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3139-subarrays-distinct-element-sum-of-squares-ii/) | [Explanation](leetcode/3139-subarrays-distinct-element-sum-of-squares-ii/Explanation.md) |
| 2926 | [Maximum Balanced Subsequence Sum](leetcode/3184-maximum-balanced-subsequence-sum/) | Hard | [Dynamic Programming](patterns/dynamic-programming.md) | JavaScript | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/3184-maximum-balanced-subsequence-sum/) | [Explanation](leetcode/3184-maximum-balanced-subsequence-sum/Explanation.md) |
| 2940 | [Find Building Where Alice and Bob Can Meet](leetcode/3181-find-building-where-alice-and-bob-can-meet/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3181-find-building-where-alice-and-bob-can-meet/) | [Explanation](leetcode/3181-find-building-where-alice-and-bob-can-meet/Explanation.md) |
| 2948 | [Make Lexicographically Smallest Array by Swapping Elements](leetcode/3219-make-lexicographically-smallest-array-by-swapping-elements/) | Medium | [Hash Map](patterns/hash-map.md) | C++ | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/3219-make-lexicographically-smallest-array-by-swapping-elements/) | [Explanation](leetcode/3219-make-lexicographically-smallest-array-by-swapping-elements/Explanation.md) |
| 2958 | [Length of Longest Subarray With at Most K Frequency](leetcode/3225-length-of-longest-subarray-with-at-most-k-frequency/) | Medium | [Hash Map](patterns/hash-map.md) | C++ | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/3225-length-of-longest-subarray-with-at-most-k-frequency/) | [Explanation](leetcode/3225-length-of-longest-subarray-with-at-most-k-frequency/Explanation.md) |
| 2996 | [Smallest Missing Integer Greater Than Sequential Prefix Sum](leetcode/3236-smallest-missing-integer-greater-than-sequential-prefix-sum/) | Easy | [Prefix Sum](patterns/prefix-sum.md) | Rust | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/3236-smallest-missing-integer-greater-than-sequential-prefix-sum/) | [Explanation](leetcode/3236-smallest-missing-integer-greater-than-sequential-prefix-sum/Explanation.md) |
| 3006 | [Find Beautiful Indices in the Given Array I](leetcode/3245-find-beautiful-indices-in-the-given-array-i/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3245-find-beautiful-indices-in-the-given-array-i/) | [Explanation](leetcode/3245-find-beautiful-indices-in-the-given-array-i/Explanation.md) |
| 3008 | [Find Beautiful Indices in the Given Array II](leetcode/3303-find-beautiful-indices-in-the-given-array-ii/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3303-find-beautiful-indices-in-the-given-array-ii/) | [Explanation](leetcode/3303-find-beautiful-indices-in-the-given-array-ii/Explanation.md) |
| 3014 | [Minimum Number of Pushes to Type Word I](leetcode/3275-minimum-number-of-pushes-to-type-word-i/) | Easy | [Hash Map](patterns/hash-map.md) | Dart | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/3275-minimum-number-of-pushes-to-type-word-i/) | [Explanation](leetcode/3275-minimum-number-of-pushes-to-type-word-i/Explanation.md) |
| 3016 | [Minimum Number of Pushes to Type Word II](leetcode/3276-minimum-number-of-pushes-to-type-word-ii/) | Medium | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3276-minimum-number-of-pushes-to-type-word-ii/) | [Explanation](leetcode/3276-minimum-number-of-pushes-to-type-word-ii/Explanation.md) |
| 3020 | [Find the Maximum Number of Elements in Subset](leetcode/3299-find-the-maximum-number-of-elements-in-subset/) | Medium | [Array / General](patterns/array-general.md) | Java | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3299-find-the-maximum-number-of-elements-in-subset/) | [Explanation](leetcode/3299-find-the-maximum-number-of-elements-in-subset/Explanation.md) |
| 3043 | [Find the Length of the Longest Common Prefix](leetcode/3329-find-the-length-of-the-longest-common-prefix/) | Medium | [Prefix Sum](patterns/prefix-sum.md) | C++ | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/3329-find-the-length-of-the-longest-common-prefix/) | [Explanation](leetcode/3329-find-the-length-of-the-longest-common-prefix/Explanation.md) |
| 3044 | [Most Frequent Prime](leetcode/3314-most-frequent-prime/) | Medium | [Hash Map](patterns/hash-map.md) | JavaScript | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/3314-most-frequent-prime/) | [Explanation](leetcode/3314-most-frequent-prime/Explanation.md) |
| 3069 | [Distribute Elements Into Two Arrays I](leetcode/3347-distribute-elements-into-two-arrays-i/) | Easy | [Hash Map](patterns/hash-map.md) | Go | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/3347-distribute-elements-into-two-arrays-i/) | [Explanation](leetcode/3347-distribute-elements-into-two-arrays-i/Explanation.md) |
| 3072 | [Distribute Elements Into Two Arrays II](leetcode/3350-distribute-elements-into-two-arrays-ii/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3350-distribute-elements-into-two-arrays-ii/) | [Explanation](leetcode/3350-distribute-elements-into-two-arrays-ii/Explanation.md) |
| 3090 | [Maximum Length Substring With Two Occurrences](leetcode/3349-maximum-length-substring-with-two-occurrences/) | Easy | [Array / General](patterns/array-general.md) | Swift | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3349-maximum-length-substring-with-two-occurrences/) | [Explanation](leetcode/3349-maximum-length-substring-with-two-occurrences/Explanation.md) |
| 3093 | [Longest Common Suffix Queries](leetcode/3376-longest-common-suffix-queries/) | Hard | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/3376-longest-common-suffix-queries/) | [Explanation](leetcode/3376-longest-common-suffix-queries/Explanation.md) |
| 3116 | [Kth Smallest Amount With Single Denomination Combination](leetcode/3375-kth-smallest-amount-with-single-denomination-combination/) | Hard | [Backtracking](patterns/backtracking.md) | Java | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/3375-kth-smallest-amount-with-single-denomination-combination/) | [Explanation](leetcode/3375-kth-smallest-amount-with-single-denomination-combination/Explanation.md) |
| 3120 | [Count the Number of Special Characters I](leetcode/3408-count-the-number-of-special-characters-i/) | Easy | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3408-count-the-number-of-special-characters-i/) | [Explanation](leetcode/3408-count-the-number-of-special-characters-i/Explanation.md) |
| 3161 | [Block Placement Queries](leetcode/3435-block-placement-queries/) | Hard | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3435-block-placement-queries/) | [Explanation](leetcode/3435-block-placement-queries/Explanation.md) |
| 3187 | [Peaks in Array](leetcode/3438-peaks-in-array/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3438-peaks-in-array/) | [Explanation](leetcode/3438-peaks-in-array/Explanation.md) |
| 3220 | [Odd and Even Transactions](leetcode/3530-odd-and-even-transactions/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/3530-odd-and-even-transactions/) | [Explanation](leetcode/3530-odd-and-even-transactions/Explanation.md) |
| 3222 | [Find the Winning Player in Coin Game](leetcode/3511-find-the-winning-player-in-coin-game/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3511-find-the-winning-player-in-coin-game/) | [Explanation](leetcode/3511-find-the-winning-player-in-coin-game/Explanation.md) |
| 3227 | [Vowels Game in a String](leetcode/3462-vowels-game-in-a-string/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3462-vowels-game-in-a-string/) | [Explanation](leetcode/3462-vowels-game-in-a-string/Explanation.md) |
| 3245 | [Alternating Groups III](leetcode/3527-alternating-groups-iii/) | Hard | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3527-alternating-groups-iii/) | [Explanation](leetcode/3527-alternating-groups-iii/Explanation.md) |
| 3283 | [Maximum Number of Moves to Kill All Pawns](leetcode/3560-maximum-number-of-moves-to-kill-all-pawns/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3560-maximum-number-of-moves-to-kill-all-pawns/) | [Explanation](leetcode/3560-maximum-number-of-moves-to-kill-all-pawns/Explanation.md) |
| 3286 | [Find a Safe Walk Through a Grid](leetcode/3558-find-a-safe-walk-through-a-grid/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Java | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3558-find-a-safe-walk-through-a-grid/) | [Explanation](leetcode/3558-find-a-safe-walk-through-a-grid/Explanation.md) |
| 3300 | [Minimum Element After Replacement With Digit Sum](leetcode/3606-minimum-element-after-replacement-with-digit-sum/) | Easy | [Math & Logic](patterns/math-logic.md) | C++ | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/3606-minimum-element-after-replacement-with-digit-sum/) | [Explanation](leetcode/3606-minimum-element-after-replacement-with-digit-sum/Explanation.md) |
| 3302 | [Find the Lexicographically Smallest Valid Sequence](leetcode/3584-find-the-lexicographically-smallest-valid-sequence/) | Medium | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3584-find-the-lexicographically-smallest-valid-sequence/) | [Explanation](leetcode/3584-find-the-lexicographically-smallest-valid-sequence/Explanation.md) |
| 3310 | [Remove Methods From Project](leetcode/3561-remove-methods-from-project/) | Medium | [Tree & Graph](patterns/tree-graph.md) | C++ | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3561-remove-methods-from-project/) | [Explanation](leetcode/3561-remove-methods-from-project/Explanation.md) |
| 3312 | [Sorted GCD Pair Queries](leetcode/3583-sorted-gcd-pair-queries/) | Hard | [Dynamic Programming](patterns/dynamic-programming.md) | PHP | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/3583-sorted-gcd-pair-queries/) | [Explanation](leetcode/3583-sorted-gcd-pair-queries/Explanation.md) |
| 3336 | [Find the Number of Subsequences With Equal GCD](leetcode/3608-find-the-number-of-subsequences-with-equal-gcd/) | Hard | [Dynamic Programming](patterns/dynamic-programming.md) | PHP | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/3608-find-the-number-of-subsequences-with-equal-gcd/) | [Explanation](leetcode/3608-find-the-number-of-subsequences-with-equal-gcd/Explanation.md) |
| 3345 | [Smallest Divisible Digit Product I](leetcode/3626-smallest-divisible-digit-product-i/) | Easy | [Tree & Graph](patterns/tree-graph.md) | Ruby | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3626-smallest-divisible-digit-product-i/) | [Explanation](leetcode/3626-smallest-divisible-digit-product-i/Explanation.md) |
| 3348 | [Smallest Divisible Digit Product II](leetcode/3635-smallest-divisible-digit-product-ii/) | Hard | [Math & Logic](patterns/math-logic.md) | Python, TypeScript | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/3635-smallest-divisible-digit-product-ii/) | [Explanation](leetcode/3635-smallest-divisible-digit-product-ii/Explanation.md) |
| 3378 | [Count Connected Components in LCM Graph](leetcode/3680-count-connected-components-in-lcm-graph/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3680-count-connected-components-in-lcm-graph/) | [Explanation](leetcode/3680-count-connected-components-in-lcm-graph/Explanation.md) |
| 3380 | [Maximum Area Rectangle With Point Constraints I](leetcode/3681-maximum-area-rectangle-with-point-constraints-i/) | Medium | [Math & Logic](patterns/math-logic.md) | JavaScript | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/3681-maximum-area-rectangle-with-point-constraints-i/) | [Explanation](leetcode/3681-maximum-area-rectangle-with-point-constraints-i/Explanation.md) |
| 3382 | [Maximum Area Rectangle With Point Constraints II](leetcode/3689-maximum-area-rectangle-with-point-constraints-ii/) | Hard | [Math & Logic](patterns/math-logic.md) | JavaScript | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/3689-maximum-area-rectangle-with-point-constraints-ii/) | [Explanation](leetcode/3689-maximum-area-rectangle-with-point-constraints-ii/Explanation.md) |
| 3414 | [Maximum Score of Non-overlapping Intervals](leetcode/3562-maximum-score-of-non-overlapping-intervals/) | Hard | [Heap](patterns/heap.md) | JavaScript | Min/Max Heap Priority Selection | O(n) | O(n) | [Code](leetcode/3562-maximum-score-of-non-overlapping-intervals/) | [Explanation](leetcode/3562-maximum-score-of-non-overlapping-intervals/Explanation.md) |
| 3421 | [Find Students Who Improved](leetcode/3767-find-students-who-improved/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/3767-find-students-who-improved/) | [Explanation](leetcode/3767-find-students-who-improved/Explanation.md) |
| 3436 | [Find Valid Emails](leetcode/3782-find-valid-emails/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/3782-find-valid-emails/) | [Explanation](leetcode/3782-find-valid-emails/Explanation.md) |
| 3451 | [Find Invalid IP Addresses](leetcode/3792-find-invalid-ip-addresses/) | Hard | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/3792-find-invalid-ip-addresses/) | [Explanation](leetcode/3792-find-invalid-ip-addresses/Explanation.md) |
| 3454 | [Separate Squares II](leetcode/3775-separate-squares-ii/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3775-separate-squares-ii/) | [Explanation](leetcode/3775-separate-squares-ii/Explanation.md) |
| 3465 | [Find Products with Valid Serial Numbers](leetcode/3803-find-products-with-valid-serial-numbers/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/3803-find-products-with-valid-serial-numbers/) | [Explanation](leetcode/3803-find-products-with-valid-serial-numbers/Explanation.md) |
| 3471 | [Find the Largest Almost Missing Integer](leetcode/3705-find-the-largest-almost-missing-integer/) | Easy | [Prefix Sum](patterns/prefix-sum.md) | Kotlin | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/3705-find-the-largest-almost-missing-integer/) | [Explanation](leetcode/3705-find-the-largest-almost-missing-integer/Explanation.md) |
| 3475 | [DNA Pattern Recognition ](leetcode/3816-dna-pattern-recognition-/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3816-dna-pattern-recognition-/) | [Explanation](leetcode/3816-dna-pattern-recognition-/Explanation.md) |
| 3482 | [Analyze Organization Hierarchy](leetcode/3828-analyze-organization-hierarchy/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3828-analyze-organization-hierarchy/) | [Explanation](leetcode/3828-analyze-organization-hierarchy/Explanation.md) |
| 3483 | [Unique 3-Digit Even Numbers](leetcode/3799-unique-3-digit-even-numbers/) | Easy | [Math & Logic](patterns/math-logic.md) | JavaScript | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/3799-unique-3-digit-even-numbers/) | [Explanation](leetcode/3799-unique-3-digit-even-numbers/Explanation.md) |
| 3497 | [Analyze Subscription Conversion ](leetcode/3848-analyze-subscription-conversion-/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3848-analyze-subscription-conversion-/) | [Explanation](leetcode/3848-analyze-subscription-conversion-/Explanation.md) |
| 3498 | [Reverse Degree of a String](leetcode/3811-reverse-degree-of-a-string/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3811-reverse-degree-of-a-string/) | [Explanation](leetcode/3811-reverse-degree-of-a-string/Explanation.md) |
| 3499 | [Maximize Active Section with Trade I](leetcode/3805-maximize-active-section-with-trade-i/) | Medium | [Monotonic Stack](patterns/monotonic-stack.md) | C++ | Monotonic Stack Filtering | O(n) | O(n) | [Code](leetcode/3805-maximize-active-section-with-trade-i/) | [Explanation](leetcode/3805-maximize-active-section-with-trade-i/Explanation.md) |
| 3501 | [Maximize Active Section with Trade II](leetcode/3804-maximize-active-section-with-trade-ii/) | Hard | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3804-maximize-active-section-with-trade-ii/) | [Explanation](leetcode/3804-maximize-active-section-with-trade-ii/Explanation.md) |
| 3513 | [Number of Unique XOR Triplets I](leetcode/3824-number-of-unique-xor-triplets-i/) | Medium | [Tree & Graph](patterns/tree-graph.md) | C++ | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3824-number-of-unique-xor-triplets-i/) | [Explanation](leetcode/3824-number-of-unique-xor-triplets-i/Explanation.md) |
| 3514 | [Number of Unique XOR Triplets II](leetcode/3820-number-of-unique-xor-triplets-ii/) | Medium | [Binary Search](patterns/binary-search.md) | C++ | Modified Binary Search | O(n) | O(1) | [Code](leetcode/3820-number-of-unique-xor-triplets-ii/) | [Explanation](leetcode/3820-number-of-unique-xor-triplets-ii/Explanation.md) |
| 3515 | [Shortest Path in a Weighted Tree](leetcode/3829-shortest-path-in-a-weighted-tree/) | Hard | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3829-shortest-path-in-a-weighted-tree/) | [Explanation](leetcode/3829-shortest-path-in-a-weighted-tree/Explanation.md) |
| 3517 | [Smallest Palindromic Rearrangement I](leetcode/3812-smallest-palindromic-rearrangement-i/) | Medium | [Tree & Graph](patterns/tree-graph.md) | C++ | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3812-smallest-palindromic-rearrangement-i/) | [Explanation](leetcode/3812-smallest-palindromic-rearrangement-i/Explanation.md) |
| 3518 | [Smallest Palindromic Rearrangement II](leetcode/3813-smallest-palindromic-rearrangement-ii/) | Hard | [Tree & Graph](patterns/tree-graph.md) | PHP | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3813-smallest-palindromic-rearrangement-ii/) | [Explanation](leetcode/3813-smallest-palindromic-rearrangement-ii/Explanation.md) |
| 3521 | [Find Product Recommendation Pairs](leetcode/3865-find-product-recommendation-pairs/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3865-find-product-recommendation-pairs/) | [Explanation](leetcode/3865-find-product-recommendation-pairs/Explanation.md) |
| 3524 | [Find X Value of Array I](leetcode/3831-find-x-value-of-array-i/) | Medium | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/3831-find-x-value-of-array-i/) | [Explanation](leetcode/3831-find-x-value-of-array-i/Explanation.md) |
| 3525 | [Find X Value of Array II](leetcode/3840-find-x-value-of-array-ii/) | Hard | [Binary Search](patterns/binary-search.md) | JavaScript | Modified Binary Search | O(n) | O(1) | [Code](leetcode/3840-find-x-value-of-array-ii/) | [Explanation](leetcode/3840-find-x-value-of-array-ii/Explanation.md) |
| 3532 | [Path Existence Queries in a Graph I](leetcode/3838-path-existence-queries-in-a-graph-i/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Java | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3838-path-existence-queries-in-a-graph-i/) | [Explanation](leetcode/3838-path-existence-queries-in-a-graph-i/Explanation.md) |
| 3534 | [Path Existence Queries in a Graph II](leetcode/3852-path-existence-queries-in-a-graph-ii/) | Hard | [Tree & Graph](patterns/tree-graph.md) | PHP | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3852-path-existence-queries-in-a-graph-ii/) | [Explanation](leetcode/3852-path-existence-queries-in-a-graph-ii/Explanation.md) |
| 3536 | [Maximum Product of Two Digits](leetcode/3859-maximum-product-of-two-digits/) | Easy | [Math & Logic](patterns/math-logic.md) | Erlang | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/3859-maximum-product-of-two-digits/) | [Explanation](leetcode/3859-maximum-product-of-two-digits/Explanation.md) |
| 3537 | [Fill a Special Grid](leetcode/3822-fill-a-special-grid/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3822-fill-a-special-grid/) | [Explanation](leetcode/3822-fill-a-special-grid/Explanation.md) |
| 3550 | [Smallest Index With Digit Sum Equal to Index](leetcode/3869-smallest-index-with-digit-sum-equal-to-index/) | Easy | [Prefix Sum](patterns/prefix-sum.md) | JavaScript | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/3869-smallest-index-with-digit-sum-equal-to-index/) | [Explanation](leetcode/3869-smallest-index-with-digit-sum-equal-to-index/Explanation.md) |
| 3551 | [Minimum Swaps to Sort by Digit Sum](leetcode/3847-minimum-swaps-to-sort-by-digit-sum/) | Medium | [Math & Logic](patterns/math-logic.md) | Python | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/3847-minimum-swaps-to-sort-by-digit-sum/) | [Explanation](leetcode/3847-minimum-swaps-to-sort-by-digit-sum/Explanation.md) |
| 3554 | [Find Category Recommendation Pairs](leetcode/3891-find-category-recommendation-pairs/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3891-find-category-recommendation-pairs/) | [Explanation](leetcode/3891-find-category-recommendation-pairs/Explanation.md) |
| 3558 | [Number of Ways to Assign Edge Weights I](leetcode/3844-number-of-ways-to-assign-edge-weights-i/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Java | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3844-number-of-ways-to-assign-edge-weights-i/) | [Explanation](leetcode/3844-number-of-ways-to-assign-edge-weights-i/Explanation.md) |
| 3559 | [Number of Ways to Assign Edge Weights II](leetcode/3842-number-of-ways-to-assign-edge-weights-ii/) | Hard | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3842-number-of-ways-to-assign-edge-weights-ii/) | [Explanation](leetcode/3842-number-of-ways-to-assign-edge-weights-ii/Explanation.md) |
| 3564 | [Seasonal Sales Analysis](leetcode/3898-seasonal-sales-analysis/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3898-seasonal-sales-analysis/) | [Explanation](leetcode/3898-seasonal-sales-analysis/Explanation.md) |
| 3568 | [Minimum Moves to Clean the Classroom](leetcode/3870-minimum-moves-to-clean-the-classroom/) | Medium | [Sliding Window](patterns/sliding-window.md) | C++ | Dynamic Sliding Window Traversal | O(n) | O(1) | [Code](leetcode/3870-minimum-moves-to-clean-the-classroom/) | [Explanation](leetcode/3870-minimum-moves-to-clean-the-classroom/Explanation.md) |
| 3570 | [Find Books with No Available Copies](leetcode/3910-find-books-with-no-available-copies/) | Easy | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3910-find-books-with-no-available-copies/) | [Explanation](leetcode/3910-find-books-with-no-available-copies/Explanation.md) |
| 3577 | [Count the Number of Computer Unlocking Permutations](leetcode/3864-count-the-number-of-computer-unlocking-permutations/) | Medium | [Backtracking](patterns/backtracking.md) | Python | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/3864-count-the-number-of-computer-unlocking-permutations/) | [Explanation](leetcode/3864-count-the-number-of-computer-unlocking-permutations/Explanation.md) |
| 3580 | [Find Consistently Improving Employees](leetcode/3921-find-consistently-improving-employees/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3921-find-consistently-improving-employees/) | [Explanation](leetcode/3921-find-consistently-improving-employees/Explanation.md) |
| 3586 | [Find COVID Recovery Patients](leetcode/3932-find-covid-recovery-patients/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3932-find-covid-recovery-patients/) | [Explanation](leetcode/3932-find-covid-recovery-patients/Explanation.md) |
| 3601 | [Find Drivers with Improved Fuel Efficiency](leetcode/3942-find-drivers-with-improved-fuel-efficiency/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3942-find-drivers-with-improved-fuel-efficiency/) | [Explanation](leetcode/3942-find-drivers-with-improved-fuel-efficiency/Explanation.md) |
| 3611 | [Find Overbooked Employees](leetcode/3943-find-overbooked-employees/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3943-find-overbooked-employees/) | [Explanation](leetcode/3943-find-overbooked-employees/Explanation.md) |
| 3612 | [Process String with Special Operations I](leetcode/3931-process-string-with-special-operations-i/) | Medium | [Tree & Graph](patterns/tree-graph.md) | Java | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3931-process-string-with-special-operations-i/) | [Explanation](leetcode/3931-process-string-with-special-operations-i/Explanation.md) |
| 3614 | [Process String with Special Operations II](leetcode/3939-process-string-with-special-operations-ii/) | Hard | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3939-process-string-with-special-operations-ii/) | [Explanation](leetcode/3939-process-string-with-special-operations-ii/Explanation.md) |
| 3617 | [Find Students with Study Spiral Pattern](leetcode/3961-find-students-with-study-spiral-pattern/) | Hard | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/3961-find-students-with-study-spiral-pattern/) | [Explanation](leetcode/3961-find-students-with-study-spiral-pattern/Explanation.md) |
| 3620 | [Network Recovery Pathways](leetcode/3919-network-recovery-pathways/) | Hard | [Tree & Graph](patterns/tree-graph.md) | PHP | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3919-network-recovery-pathways/) | [Explanation](leetcode/3919-network-recovery-pathways/Explanation.md) |
| 3622 | [Check Divisibility by Digit Sum and Product](leetcode/3918-check-divisibility-by-digit-sum-and-product/) | Easy | [Math & Logic](patterns/math-logic.md) | C | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/3918-check-divisibility-by-digit-sum-and-product/) | [Explanation](leetcode/3918-check-divisibility-by-digit-sum-and-product/Explanation.md) |
| 3624 | [Number of Integers With Popcount-Depth Equal to K II](leetcode/3941-number-of-integers-with-popcount-depth-equal-to-k-ii/) | Hard | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/3941-number-of-integers-with-popcount-depth-equal-to-k-ii/) | [Explanation](leetcode/3941-number-of-integers-with-popcount-depth-equal-to-k-ii/Explanation.md) |
| 3626 | [Find Stores with Inventory Imbalance](leetcode/3971-find-stores-with-inventory-imbalance/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/3971-find-stores-with-inventory-imbalance/) | [Explanation](leetcode/3971-find-stores-with-inventory-imbalance/Explanation.md) |
| 3627 | [Maximum Median Sum of Subsequences of Size 3](leetcode/3766-maximum-median-sum-of-subsequences-of-size-3/) | Medium | [Dynamic Programming](patterns/dynamic-programming.md) | Python | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/3766-maximum-median-sum-of-subsequences-of-size-3/) | [Explanation](leetcode/3766-maximum-median-sum-of-subsequences-of-size-3/Explanation.md) |
| 3629 | [Minimum Jumps to Reach End via Prime Teleportation](leetcode/3933-minimum-jumps-to-reach-end-via-prime-teleportation/) | Medium | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3933-minimum-jumps-to-reach-end-via-prime-teleportation/) | [Explanation](leetcode/3933-minimum-jumps-to-reach-end-via-prime-teleportation/Explanation.md) |
| 3633 | [Earliest Finish Time for Land and Water Rides I](leetcode/3965-earliest-finish-time-for-land-and-water-rides-i/) | Easy | [Array / General](patterns/array-general.md) | Kotlin | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3965-earliest-finish-time-for-land-and-water-rides-i/) | [Explanation](leetcode/3965-earliest-finish-time-for-land-and-water-rides-i/Explanation.md) |
| 3635 | [Earliest Finish Time for Land and Water Rides II](leetcode/3967-earliest-finish-time-for-land-and-water-rides-ii/) | Medium | [Array / General](patterns/array-general.md) | Java | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3967-earliest-finish-time-for-land-and-water-rides-ii/) | [Explanation](leetcode/3967-earliest-finish-time-for-land-and-water-rides-ii/Explanation.md) |
| 3636 | [Threshold Majority Queries](leetcode/3955-threshold-majority-queries/) | Hard | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/3955-threshold-majority-queries/) | [Explanation](leetcode/3955-threshold-majority-queries/Explanation.md) |
| 3642 | [Find Books with Polarized Opinions](leetcode/3996-find-books-with-polarized-opinions/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/3996-find-books-with-polarized-opinions/) | [Explanation](leetcode/3996-find-books-with-polarized-opinions/Explanation.md) |
| 3653 | [XOR After Range Multiplication Queries I](leetcode/3974-xor-after-range-multiplication-queries-i/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/3974-xor-after-range-multiplication-queries-i/) | [Explanation](leetcode/3974-xor-after-range-multiplication-queries-i/Explanation.md) |
| 3657 | [Find Loyal Customers](leetcode/4025-find-loyal-customers/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/4025-find-loyal-customers/) | [Explanation](leetcode/4025-find-loyal-customers/Explanation.md) |
| 3658 | [GCD of Odd and Even Sums](leetcode/3995-gcd-of-odd-and-even-sums/) | Easy | [Two Pointers](patterns/two-pointers.md) | Kotlin | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/3995-gcd-of-odd-and-even-sums/) | [Explanation](leetcode/3995-gcd-of-odd-and-even-sums/Explanation.md) |
| 3660 | [Jump Game IX](leetcode/3981-jump-game-ix/) | Medium | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/3981-jump-game-ix/) | [Explanation](leetcode/3981-jump-game-ix/Explanation.md) |
| 3671 | [Sum of Beautiful Subsequences](leetcode/3989-sum-of-beautiful-subsequences/) | Hard | [Dynamic Programming](patterns/dynamic-programming.md) | Python | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/3989-sum-of-beautiful-subsequences/) | [Explanation](leetcode/3989-sum-of-beautiful-subsequences/Explanation.md) |
| 3673 | [Find Zombie Sessions](leetcode/4043-find-zombie-sessions/) | Hard | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/4043-find-zombie-sessions/) | [Explanation](leetcode/4043-find-zombie-sessions/Explanation.md) |
| 3674 | [Minimum Operations to Equalize Array](leetcode/3998-minimum-operations-to-equalize-array/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/3998-minimum-operations-to-equalize-array/) | [Explanation](leetcode/3998-minimum-operations-to-equalize-array/Explanation.md) |
| 3689 | [Maximum Total Subarray Value I](leetcode/4005-maximum-total-subarray-value-i/) | Medium | [Binary Search](patterns/binary-search.md) | Java | Modified Binary Search | O(n) | O(1) | [Code](leetcode/4005-maximum-total-subarray-value-i/) | [Explanation](leetcode/4005-maximum-total-subarray-value-i/Explanation.md) |
| 3691 | [Maximum Total Subarray Value II](leetcode/4007-maximum-total-subarray-value-ii/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4007-maximum-total-subarray-value-ii/) | [Explanation](leetcode/4007-maximum-total-subarray-value-ii/Explanation.md) |
| 3699 | [Number of ZigZag Arrays I](leetcode/3962-number-of-zigzag-arrays-i/) | Hard | [Hash Map](patterns/hash-map.md) | PHP | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/3962-number-of-zigzag-arrays-i/) | [Explanation](leetcode/3962-number-of-zigzag-arrays-i/Explanation.md) |
| 3700 | [Number of ZigZag Arrays II](leetcode/3964-number-of-zigzag-arrays-ii/) | Hard | [Tree & Graph](patterns/tree-graph.md) | PHP | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3964-number-of-zigzag-arrays-ii/) | [Explanation](leetcode/3964-number-of-zigzag-arrays-ii/Explanation.md) |
| 3702 | [Longest Subsequence With Non-Zero Bitwise XOR](leetcode/4033-longest-subsequence-with-non-zero-bitwise-xor/) | Medium | [Dynamic Programming](patterns/dynamic-programming.md) | C++ | Memoization & State Transition | O(n) | O(n) | [Code](leetcode/4033-longest-subsequence-with-non-zero-bitwise-xor/) | [Explanation](leetcode/4033-longest-subsequence-with-non-zero-bitwise-xor/Explanation.md) |
| 3705 | [Find Golden Hour Customers](leetcode/4091-find-golden-hour-customers/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4091-find-golden-hour-customers/) | [Explanation](leetcode/4091-find-golden-hour-customers/Explanation.md) |
| 3716 | [Find Churn Risk Customers](leetcode/4103-find-churn-risk-customers/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4103-find-churn-risk-customers/) | [Explanation](leetcode/4103-find-churn-risk-customers/Explanation.md) |
| 3718 | [Smallest Missing Multiple of K](leetcode/4080-smallest-missing-multiple-of-k/) | Easy | [Prefix Sum](patterns/prefix-sum.md) | C# | Prefix Sum Precomputation | O(n) | O(n) | [Code](leetcode/4080-smallest-missing-multiple-of-k/) | [Explanation](leetcode/4080-smallest-missing-multiple-of-k/Explanation.md) |
| 3719 | [Longest Balanced Subarray I](leetcode/4045-longest-balanced-subarray-i/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4045-longest-balanced-subarray-i/) | [Explanation](leetcode/4045-longest-balanced-subarray-i/Explanation.md) |
| 3720 | [Lexicographically Smallest Permutation Greater Than Target](leetcode/4020-lexicographically-smallest-permutation-greater-than-target/) | Medium | [Backtracking](patterns/backtracking.md) | C++ | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/4020-lexicographically-smallest-permutation-greater-than-target/) | [Explanation](leetcode/4020-lexicographically-smallest-permutation-greater-than-target/Explanation.md) |
| 3721 | [Longest Balanced Subarray II](leetcode/4047-longest-balanced-subarray-ii/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4047-longest-balanced-subarray-ii/) | [Explanation](leetcode/4047-longest-balanced-subarray-ii/Explanation.md) |
| 3723 | [Maximize Sum of Squares of Digits](leetcode/4084-maximize-sum-of-squares-of-digits/) | Medium | [Math & Logic](patterns/math-logic.md) | Python | Mathematical Simulation & Modular Arithmetic | O(n) | O(1) | [Code](leetcode/4084-maximize-sum-of-squares-of-digits/) | [Explanation](leetcode/4084-maximize-sum-of-squares-of-digits/Explanation.md) |
| 3727 | [Maximum Alternating Sum of Squares](leetcode/4078-maximum-alternating-sum-of-squares/) | Medium | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/4078-maximum-alternating-sum-of-squares/) | [Explanation](leetcode/4078-maximum-alternating-sum-of-squares/Explanation.md) |
| 3731 | [Find Missing Elements](leetcode/4107-find-missing-elements/) | Easy | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4107-find-missing-elements/) | [Explanation](leetcode/4107-find-missing-elements/Explanation.md) |
| 3734 | [Lexicographically Smallest Palindromic Permutation Greater Than Target](leetcode/4037-lexicographically-smallest-palindromic-permutation-greater-than-target/) | Hard | [Backtracking](patterns/backtracking.md) | Java | Backtracking Recursive Search | O(n) | O(1) | [Code](leetcode/4037-lexicographically-smallest-palindromic-permutation-greater-than-target/) | [Explanation](leetcode/4037-lexicographically-smallest-palindromic-permutation-greater-than-target/Explanation.md) |
| 3737 | [Count Subarrays With Majority Element I](leetcode/4074-count-subarrays-with-majority-element-i/) | Medium | [Monotonic Stack](patterns/monotonic-stack.md) | Java | Monotonic Stack Filtering | O(n) | O(n) | [Code](leetcode/4074-count-subarrays-with-majority-element-i/) | [Explanation](leetcode/4074-count-subarrays-with-majority-element-i/Explanation.md) |
| 3739 | [Count Subarrays With Majority Element II](leetcode/4075-count-subarrays-with-majority-element-ii/) | Hard | [Array / General](patterns/array-general.md) | PHP | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4075-count-subarrays-with-majority-element-ii/) | [Explanation](leetcode/4075-count-subarrays-with-majority-element-ii/Explanation.md) |
| 3742 | [Maximum Path Score in a Grid](leetcode/3986-maximum-path-score-in-a-grid/) | Medium | [Tree & Graph](patterns/tree-graph.md) | C++ | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/3986-maximum-path-score-in-a-grid/) | [Explanation](leetcode/3986-maximum-path-score-in-a-grid/Explanation.md) |
| 3751 | [Total Waviness of Numbers in Range I](leetcode/4057-total-waviness-of-numbers-in-range-i/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | Java | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/4057-total-waviness-of-numbers-in-range-i/) | [Explanation](leetcode/4057-total-waviness-of-numbers-in-range-i/Explanation.md) |
| 3753 | [Total Waviness of Numbers in Range II](leetcode/4128-total-waviness-of-numbers-in-range-ii/) | Hard | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/4128-total-waviness-of-numbers-in-range-ii/) | [Explanation](leetcode/4128-total-waviness-of-numbers-in-range-ii/Explanation.md) |
| 3754 | [Concatenate Non-Zero Digits and Multiply by Sum I](leetcode/4135-concatenate-non-zero-digits-and-multiply-by-sum-i/) | Easy | [Bit Manipulation](patterns/bit-manipulation.md) | Kotlin | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/4135-concatenate-non-zero-digits-and-multiply-by-sum-i/) | [Explanation](leetcode/4135-concatenate-non-zero-digits-and-multiply-by-sum-i/Explanation.md) |
| 3756 | [Concatenate Non-Zero Digits and Multiply by Sum II](leetcode/4136-concatenate-non-zero-digits-and-multiply-by-sum-ii/) | Medium | [Bit Manipulation](patterns/bit-manipulation.md) | Java | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/4136-concatenate-non-zero-digits-and-multiply-by-sum-ii/) | [Explanation](leetcode/4136-concatenate-non-zero-digits-and-multiply-by-sum-ii/Explanation.md) |
| 3759 | [Count Elements With at Least K Greater Values](leetcode/4141-count-elements-with-at-least-k-greater-values/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4141-count-elements-with-at-least-k-greater-values/) | [Explanation](leetcode/4141-count-elements-with-at-least-k-greater-values/Explanation.md) |
| 3762 | [Minimum Operations to Equalize Subarrays](leetcode/4022-minimum-operations-to-equalize-subarrays/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4022-minimum-operations-to-equalize-subarrays/) | [Explanation](leetcode/4022-minimum-operations-to-equalize-subarrays/Explanation.md) |
| 3764 | [Most Common Course Pairs](leetcode/4169-most-common-course-pairs/) | Hard | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/4169-most-common-course-pairs/) | [Explanation](leetcode/4169-most-common-course-pairs/Explanation.md) |
| 3793 | [Find Users with High Token Usage](leetcode/4195-find-users-with-high-token-usage/) | Easy | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/4195-find-users-with-high-token-usage/) | [Explanation](leetcode/4195-find-users-with-high-token-usage/Explanation.md) |
| 3808 | [Find Emotionally Consistent Users](leetcode/4208-find-emotionally-consistent-users/) | Medium | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/4208-find-emotionally-consistent-users/) | [Explanation](leetcode/4208-find-emotionally-consistent-users/Explanation.md) |
| 3826 | [Minimum Partition Score](leetcode/4121-minimum-partition-score/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4121-minimum-partition-score/) | [Explanation](leetcode/4121-minimum-partition-score/Explanation.md) |
| 3828 | [Final Element After Subarray Deletions](leetcode/4122-final-element-after-subarray-deletions/) | Medium | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4122-final-element-after-subarray-deletions/) | [Explanation](leetcode/4122-final-element-after-subarray-deletions/Explanation.md) |
| 3832 | [Find Users with Persistent Behavior Patterns](leetcode/4227-find-users-with-persistent-behavior-patterns/) | Hard | [Database / SQL](patterns/sql-database.md) | SQL | SQL Query / Relational Join & Window Function | O(n) | O(n) | [Code](leetcode/4227-find-users-with-persistent-behavior-patterns/) | [Explanation](leetcode/4227-find-users-with-persistent-behavior-patterns/Explanation.md) |
| 3838 | [Weighted Word Mapping](leetcode/4216-weighted-word-mapping/) | Easy | [Hash Map](patterns/hash-map.md) | Kotlin | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/4216-weighted-word-mapping/) | [Explanation](leetcode/4216-weighted-word-mapping/Explanation.md) |
| 3841 | [Palindromic Path Queries in a Tree](leetcode/4209-palindromic-path-queries-in-a-tree/) | Hard | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/4209-palindromic-path-queries-in-a-tree/) | [Explanation](leetcode/4209-palindromic-path-queries-in-a-tree/Explanation.md) |
| 3855 | [Sum of K-Digit Numbers in a Range](leetcode/4239-sum-of-k-digit-numbers-in-a-range/) | Hard | [Bit Manipulation](patterns/bit-manipulation.md) | Python | Bitwise Masking & Bit Shift | O(n) | O(1) | [Code](leetcode/4239-sum-of-k-digit-numbers-in-a-range/) | [Explanation](leetcode/4239-sum-of-k-digit-numbers-in-a-range/Explanation.md) |
| 3864 | [Minimum Cost to Partition a Binary String](leetcode/4192-minimum-cost-to-partition-a-binary-string/) | Hard | [Tree & Graph](patterns/tree-graph.md) | Python | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/4192-minimum-cost-to-partition-a-binary-string/) | [Explanation](leetcode/4192-minimum-cost-to-partition-a-binary-string/Explanation.md) |
| 3867 | [Sum of GCD of Formed Pairs](leetcode/4242-sum-of-gcd-of-formed-pairs/) | Medium | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4242-sum-of-gcd-of-formed-pairs/) | [Explanation](leetcode/4242-sum-of-gcd-of-formed-pairs/Explanation.md) |
| 3870 | [Count Commas in Range](leetcode/4245-count-commas-in-range/) | Easy | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/4245-count-commas-in-range/) | [Explanation](leetcode/4245-count-commas-in-range/Explanation.md) |
| 3871 | [Count Commas in Range II](leetcode/4248-count-commas-in-range-ii/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4248-count-commas-in-range-ii/) | [Explanation](leetcode/4248-count-commas-in-range-ii/Explanation.md) |
| 3875 | [Construct Uniform Parity Array I](leetcode/4256-construct-uniform-parity-array-i/) | Easy | [Binary Search](patterns/binary-search.md) | C++ | Modified Binary Search | O(n) | O(1) | [Code](leetcode/4256-construct-uniform-parity-array-i/) | [Explanation](leetcode/4256-construct-uniform-parity-array-i/Explanation.md) |
| 3876 | [Construct Uniform Parity Array II](leetcode/4258-construct-uniform-parity-array-ii/) | Medium | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4258-construct-uniform-parity-array-ii/) | [Explanation](leetcode/4258-construct-uniform-parity-array-ii/Explanation.md) |
| 3903 | [Smallest Stable Index I](leetcode/4284-smallest-stable-index-i/) | Easy | [Tree & Graph](patterns/tree-graph.md) | JavaScript | Depth-First Search (DFS) / Breadth-First Search (BFS) | O(n) | O(n) | [Code](leetcode/4284-smallest-stable-index-i/) | [Explanation](leetcode/4284-smallest-stable-index-i/Explanation.md) |
| 3904 | [Smallest Stable Index II](leetcode/4285-smallest-stable-index-ii/) | Medium | [Array / General](patterns/array-general.md) | JavaScript | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4285-smallest-stable-index-ii/) | [Explanation](leetcode/4285-smallest-stable-index-ii/Explanation.md) |
| 3943 | [Number of Pairs After Increment](leetcode/4076-number-of-pairs-after-increment/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4076-number-of-pairs-after-increment/) | [Explanation](leetcode/4076-number-of-pairs-after-increment/Explanation.md) |
| 3962 | [Maximum Subarray Sum After at Most K Swaps](leetcode/4246-maximum-subarray-sum-after-at-most-k-swaps/) | Hard | [Array / General](patterns/array-general.md) | C++ | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4246-maximum-subarray-sum-after-at-most-k-swaps/) | [Explanation](leetcode/4246-maximum-subarray-sum-after-at-most-k-swaps/Explanation.md) |
| 4011 | [Count Subarrays With Even Odd Ratio I](leetcode/4323-count-subarrays-with-even-odd-ratio-i/) | Medium | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/4323-count-subarrays-with-even-odd-ratio-i/) | [Explanation](leetcode/4323-count-subarrays-with-even-odd-ratio-i/Explanation.md) |
| 4013 | [Count Subarrays With Even Odd Ratio II](leetcode/4324-count-subarrays-with-even-odd-ratio-ii/) | Hard | [Two Pointers](patterns/two-pointers.md) | Python | Two Pointer Convergence & Scanning | O(n) | O(1) | [Code](leetcode/4324-count-subarrays-with-even-odd-ratio-ii/) | [Explanation](leetcode/4324-count-subarrays-with-even-odd-ratio-ii/Explanation.md) |
| 4017 | [Peaks in Array II](leetcode/4336-peaks-in-array-ii/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4336-peaks-in-array-ii/) | [Explanation](leetcode/4336-peaks-in-array-ii/Explanation.md) |
| 4033 | [Valid K-Unique Subarrays I](leetcode/3988-valid-k-unique-subarrays-i/) | Hard | [Hash Map](patterns/hash-map.md) | Python | Complement Lookup / Hash Table Frequency | O(n) | O(n) | [Code](leetcode/3988-valid-k-unique-subarrays-i/) | [Explanation](leetcode/3988-valid-k-unique-subarrays-i/Explanation.md) |
| 4051 | [Count Subarrays with Distant Sums](leetcode/4317-count-subarrays-with-distant-sums/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4317-count-subarrays-with-distant-sums/) | [Explanation](leetcode/4317-count-subarrays-with-distant-sums/Explanation.md) |
| 4055 | [Count Shadow Pairs II](leetcode/4326-count-shadow-pairs-ii/) | Hard | [Array / General](patterns/array-general.md) | Python | In-Place Array Traversal & Index Mapping | O(n) | O(1) | [Code](leetcode/4326-count-shadow-pairs-ii/) | [Explanation](leetcode/4326-count-shadow-pairs-ii/Explanation.md) |
| 4062 | [Transform Array Using Pair Operations](leetcode/4398-transform-array-using-pair-operations/) | Medium | [Stack & Queue](patterns/stack-queue.md) | Python | Stack Push / Pop Parsing | O(n) | O(n) | [Code](leetcode/4398-transform-array-using-pair-operations/) | [Explanation](leetcode/4398-transform-array-using-pair-operations/Explanation.md) |