Algorithms: Search 2D Matrix for value

DIRECTORY.md

@@ -371,6 +371,8 @@
         * [Test Plates Between Candles](https://github.com/BrianLusina/PythonSnips/blob/master/algorithms/search/binary_search/plates_between_candles/test_plates_between_candles.py)
       * Rotated Sorted Array
         * [Test Search Rotated Sorted Array](https://github.com/BrianLusina/PythonSnips/blob/master/algorithms/search/binary_search/rotated_sorted_array/test_search_rotated_sorted_array.py)
+      * Search 2D Matrix
+        * [Test Search 2D Matrix](https://github.com/BrianLusina/PythonSnips/blob/master/algorithms/search/binary_search/search_2d_matrix/test_search_2d_matrix.py)
       * Search Range
         * [Test Search Range](https://github.com/BrianLusina/PythonSnips/blob/master/algorithms/search/binary_search/search_range/test_search_range.py)
       * Single Non Duplicate

algorithms/search/binary_search/search_2d_matrix/README.md

@@ -0,0 +1,14 @@
+# Search a 2D Matrix
+
+Given a two dimensional integer array matrix with m rows and n columns, determine whether the integer target exists in
+matrix. Return true if target is present, otherwise return false.
+
+The array matrix is sorted such that each row is in nondecreasing order, and the first element of each row is greater
+than the last element of the previous row.
+
+## Constraints
+
+- m == matrix.length
+- n == matrix[i].length
+- 1 <= m,n <= 100
+- -10^4 <= matrix[i][j], target <= 10^4

algorithms/search/binary_search/search_2d_matrix/__init__.py

@@ -0,0 +1,69 @@
+from typing import List
+
+
+def search_matrix(matrix: List[List[int]], target: int) -> bool:
+    """
+    Search a 2D matrix for a target value. If the target value is found, return True, otherwise return False.
+    Args:
+        matrix (List[List[int]]): 2D matrix to search in.
+        target (int): Target value to search for.
+    Returns:
+        bool: True if the target value is found in the matrix, False otherwise.
+    """
+    if not matrix:
+        return False
+    if not matrix[0]:
+        return False
+
+    n_rows = len(matrix)
+    n_cols = len(matrix[0])
+
+    left, right = 0, n_rows * n_cols - 1
+    while left <= right:
+        mid = (left + right) // 2
+        row, col = mid // n_cols, mid % n_cols
+        if matrix[row][col] == target:
+            return True
+        elif matrix[row][col] < target:
+            left = mid + 1
+        else:
+            right = mid - 1
+    return False
+
+
+def search_matrix_2(matrix: List[List[int]], target: int) -> bool:
+    """
+    Search a 2D matrix for a target value. If the target value is found, return True, otherwise return False.
+    Args:
+        matrix (List[List[int]]): 2D matrix to search in.
+        target (int): Target value to search for.
+    Returns:
+        bool: True if the target value is found in the matrix, False otherwise.
+    """
+    # Get dimensions of the matrix
+    num_rows, num_cols = len(matrix), len(matrix[0])
+
+    # Initialize binary search boundaries
+    # Treat the 2D matrix as a flattened 1D array
+    left, right = 0, num_rows * num_cols - 1
+    first_true_index = -1
+
+    # Binary search using the template: find first index where element >= target
+    while left <= right:
+        mid = (left + right) // 2
+
+        # Convert 1D index to 2D coordinates
+        row, col = divmod(mid, num_cols)
+
+        # Feasible condition: matrix[row][col] >= target
+        if matrix[row][col] >= target:
+            first_true_index = mid
+            right = mid - 1
+        else:
+            left = mid + 1
+
+    # Check if first_true_index points to the target
+    if first_true_index == -1:
+        return False
+    row, col = divmod(first_true_index, num_cols)
+    return matrix[row][col] == target

algorithms/search/binary_search/search_2d_matrix/test_search_2d_matrix.py

@@ -0,0 +1,39 @@
+import unittest
+from typing import List
+from parameterized import parameterized
+from utils.test_utils import custom_test_name_func
+from algorithms.search.binary_search.search_2d_matrix import (
+    search_matrix,
+    search_matrix_2,
+)
+
+SEARCH_2D_MATRIX_TEST_CASES = [
+    ([[-8, -3, 1, 4], [7, 9, 13, 18], [21, 26, 31, 40]], 13, True),
+    ([[-6]], 5, False),
+    ([[-5, -2, 0], [3, 6, 10]], -9, False),
+    ([[-10, -4, 2, 9, 15, 22]], 9, True),
+    ([[-9], [-1], [5], [12], [20]], 6, False),
+    ([[0]], 0, True),
+    ([[1, 3, 5, 7], [10, 11, 16, 20], [23, 30, 34, 60]], 3, True),
+    ([[1, 3, 5, 7], [10, 11, 16, 20], [23, 30, 34, 60]], 13, False),
+]
+
+
+class Search2DMatrixTestCase(unittest.TestCase):
+    @parameterized.expand(SEARCH_2D_MATRIX_TEST_CASES, name_func=custom_test_name_func)
+    def test_search_2d_matrix(
+        self, matrix: List[List[int]], target: int, expected: bool
+    ):
+        actual = search_matrix(matrix, target)
+        self.assertEqual(expected, actual)
+
+    @parameterized.expand(SEARCH_2D_MATRIX_TEST_CASES, name_func=custom_test_name_func)
+    def test_search_2d_matrix_2(
+        self, matrix: List[List[int]], target: int, expected: bool
+    ):
+        actual = search_matrix_2(matrix, target)
+        self.assertEqual(expected, actual)
+
+
+if __name__ == "__main__":
+    unittest.main()