Merge branch 'master' into master

Author: cclauss

DIRECTORY.md

@@ -262,8 +262,10 @@
 
 ## [Data Structures](data_structures)
   * Arrays
+    * [Dynamic Array](data_structures/arrays/dynamic_array.py)
     * [Equilibrium Index In Array](data_structures/arrays/equilibrium_index_in_array.py)
     * [Find Triplets With 0 Sum](data_structures/arrays/find_triplets_with_0_sum.py)
+    * [Gas Station](data_structures/arrays/gas_station.py)
     * [Index 2D Array In 1D](data_structures/arrays/index_2d_array_in_1d.py)
     * [Kth Largest Element](data_structures/arrays/kth_largest_element.py)
     * [Median Two Array](data_structures/arrays/median_two_array.py)
@@ -303,6 +305,7 @@
     * [Mirror Binary Tree](data_structures/binary_tree/mirror_binary_tree.py)
     * [Non Recursive Segment Tree](data_structures/binary_tree/non_recursive_segment_tree.py)
     * [Number Of Possible Binary Trees](data_structures/binary_tree/number_of_possible_binary_trees.py)
+    * [Persistent Segment Tree](data_structures/binary_tree/persistent_segment_tree.py)
     * [Red Black Tree](data_structures/binary_tree/red_black_tree.py)
     * [Segment Tree](data_structures/binary_tree/segment_tree.py)
     * [Segment Tree Other](data_structures/binary_tree/segment_tree_other.py)
@@ -540,12 +543,15 @@
     * [Test Send File](file_transfer/tests/test_send_file.py)
 
 ## [Financial](financial)
+  * [Annuity Due Future Value](financial/annuity_due_future_value.py)
   * [Equated Monthly Installments](financial/equated_monthly_installments.py)
   * [Expected Shortfall](financial/expected_shortfall.py)
   * [Exponential Moving Average](financial/exponential_moving_average.py)
+  * [Fractional Differentiation](financial/fractional_differentiation.py)
   * [Interest](financial/interest.py)
   * [Kelly Criterion](financial/kelly_criterion.py)
   * [Macaulay Duration](financial/macaulay_duration.py)
+  * [Ordinary Annuity Future Value](financial/ordinary_annuity_future_value.py)
   * [Present Value](financial/present_value.py)
   * [Price Plus Tax](financial/price_plus_tax.py)
   * [Sharpe Ratio](financial/sharpe_ratio.py)
@@ -629,6 +635,7 @@
   * [Dijkstra Binary Grid](graphs/dijkstra_binary_grid.py)
   * [Dinic](graphs/dinic.py)
   * [Directed And Undirected Weighted Graph](graphs/directed_and_undirected_weighted_graph.py)
+  * [Edmonds Blossom Algorithm](graphs/edmonds_blossom_algorithm.py)
   * [Edmonds Karp Multiple Source And Sink](graphs/edmonds_karp_multiple_source_and_sink.py)
   * [Eulerian Path And Circuit For Undirected Graph](graphs/eulerian_path_and_circuit_for_undirected_graph.py)
   * [Even Tree](graphs/even_tree.py)
@@ -638,7 +645,9 @@
   * [Gale Shapley Bigraph](graphs/gale_shapley_bigraph.py)
   * [Graph Adjacency List](graphs/graph_adjacency_list.py)
   * [Graph Adjacency Matrix](graphs/graph_adjacency_matrix.py)
+  * [Graph Centrality](graphs/graph_centrality.py)
   * [Graph List](graphs/graph_list.py)
+  * [Graph Peripherality](graphs/graph_peripherality.py)
   * [Graphs Floyd Warshall](graphs/graphs_floyd_warshall.py)
   * [Greedy Best First](graphs/greedy_best_first.py)
   * [Greedy Min Vertex Cover](graphs/greedy_min_vertex_cover.py)
@@ -664,13 +673,15 @@
   * [Strongly Connected Components](graphs/strongly_connected_components.py)
   * [Tarjans Scc](graphs/tarjans_scc.py)
   * Tests
+    * [Test Edmonds Blossom Algorithm](graphs/tests/test_edmonds_blossom_algorithm.py)
     * [Test Graphs Floyd Warshall](graphs/tests/test_graphs_floyd_warshall.py)
     * [Test Johnson](graphs/tests/test_johnson.py)
     * [Test Min Spanning Tree Kruskal](graphs/tests/test_min_spanning_tree_kruskal.py)
     * [Test Min Spanning Tree Prim](graphs/tests/test_min_spanning_tree_prim.py)
   * [Travelling Salesman Problem](graphs/travelling_salesman_problem.py)
 
 ## [Greedy Methods](greedy_methods)
+  * [Activity Selection](greedy_methods/activity_selection.py)
   * [Best Time To Buy And Sell Stock](greedy_methods/best_time_to_buy_and_sell_stock.py)
   * [Fractional Cover Problem](greedy_methods/fractional_cover_problem.py)
   * [Fractional Knapsack](greedy_methods/fractional_knapsack.py)
@@ -885,6 +896,7 @@
     * [Nevilles Method](maths/numerical_analysis/nevilles_method.py)
     * [Newton Forward Interpolation](maths/numerical_analysis/newton_forward_interpolation.py)
     * [Newton Raphson](maths/numerical_analysis/newton_raphson.py)
+    * [Nth Root](maths/numerical_analysis/nth_root.py)
     * [Numerical Integration](maths/numerical_analysis/numerical_integration.py)
     * [Proper Fractions](maths/numerical_analysis/proper_fractions.py)
     * [Runge Kutta](maths/numerical_analysis/runge_kutta.py)
@@ -960,6 +972,7 @@
     * [Happy Number](maths/special_numbers/happy_number.py)
     * [Harshad Numbers](maths/special_numbers/harshad_numbers.py)
     * [Hexagonal Number](maths/special_numbers/hexagonal_number.py)
+    * [Jacobsthal Number](maths/special_numbers/jacobsthal_number.py)
     * [Kaprekar Constant](maths/special_numbers/kaprekar_constant.py)
     * [Kaprekar Number](maths/special_numbers/kaprekar_number.py)
     * [Krishnamurthy Number](maths/special_numbers/krishnamurthy_number.py)
@@ -1052,6 +1065,7 @@
     * [Nesterov Accelerated Sgd](neural_network/optimizers/nesterov_accelerated_sgd.py)
   * [Perceptron](neural_network/perceptron.py)
   * [Simple Neural Network](neural_network/simple_neural_network.py)
+  * [Sliding Window Attention](neural_network/sliding_window_attention.py)
   * [Two Hidden Layers Neural Network](neural_network/two_hidden_layers_neural_network.py)
 
 ## [Other](other)
@@ -1592,9 +1606,11 @@
   * [Knuth Morris Pratt](strings/knuth_morris_pratt.py)
   * [Largest Smallest Words](strings/largest_smallest_words.py)
   * [Levenshtein Distance](strings/levenshtein_distance.py)
+  * [Longest Word In Sentence](strings/longest_word_in_sentence.py)
   * [Lower](strings/lower.py)
   * [Manacher](strings/manacher.py)
   * [Min Cost String Conversion](strings/min_cost_string_conversion.py)
+  * [Min Window Substring](strings/min_window_substring.py)
   * [Naive String Search](strings/naive_string_search.py)
   * [Ngram](strings/ngram.py)
   * [Palindrome](strings/palindrome.py)
@@ -1606,6 +1622,7 @@
   * [Reverse Words](strings/reverse_words.py)
   * [Snake Case To Camel Pascal Case](strings/snake_case_to_camel_pascal_case.py)
   * [Split](strings/split.py)
+  * [String Is Valid Number](strings/string_is_valid_number.py)
   * [String Switch Case](strings/string_switch_case.py)
   * [Strip](strings/strip.py)
   * [Suffix Automaton](strings/suffix_automaton.py)

data_structures/arrays/dynamic_array.py

@@ -0,0 +1,127 @@
+class DynamicArray:
+    def __init__(self) -> None:
+        self.size = 0  # Number of elements in the array
+        self.capacity = 1  # Initial capacity of the array
+        self.array = [None] * self.capacity  # Create an array with initial capacity
+
+    def append(self, item: int) -> None:
+        """
+        The function adds an item to the end of the dynamic array.
+
+        Runtime : O(1) amortized
+        Space: O(1) amortized
+
+        >>> arr = DynamicArray()
+        >>> arr.append(1)
+        >>> arr.append(2)
+        >>> arr.append(3)
+        >>> arr.array[:arr.size]  # Display only the filled part of the array
+        [1, 2, 3]
+        >>> arr.append(4)
+        >>> arr.array[:arr.size]
+        [1, 2, 3, 4]
+        >>> arr.append(5)
+        >>> arr.array[:arr.size]
+        [1, 2, 3, 4, 5]
+        """
+        if self.size == self.capacity:
+            self._resize(2 * self.capacity)  # Double the capacity
+
+        self.array[self.size] = item
+        self.size += 1
+
+    def _resize(self, new_capacity: int) -> None:
+        """
+        Resizes the array to the new capacity.
+
+        Runtime : O(n)
+        Space: O(n)
+
+        >>> arr = DynamicArray()
+        >>> arr.append(1)
+        >>> arr.append(2)
+        >>> arr._resize(10)
+        >>> arr.capacity
+        10
+        >>> arr.array[:arr.size]
+        [1, 2]
+        """
+        new_array = [None] * new_capacity
+        for i in range(self.size):
+            new_array[i] = self.array[i]
+        self.array = new_array
+        self.capacity = new_capacity
+
+    def get(self, index: int) -> int:
+        """
+        The function returns the item at the specified index.
+
+        Runtime : O(1)
+        Space: O(1)
+
+        >>> arr = DynamicArray()
+        >>> arr.append(1)
+        >>> arr.append(2)
+        >>> arr.get(0)
+        1
+        >>> arr.get(1)
+        2
+        >>> arr.get(2)
+        Traceback (most recent call last):
+        ...
+        IndexError: index out of range
+        >>> arr.get(-1)
+        Traceback (most recent call last):
+        ...
+        IndexError: index out of range
+        """
+        if index < 0 or index >= self.size:
+            raise IndexError("index out of range")
+        return self.array[index]
+
+    def __setitem__(self, index: int, value: int) -> None:
+        if index < 0 or index >= self.size:
+            raise IndexError("index out of range")
+        self.array[index] = value
+
+    def __len__(self) -> int:
+        """
+        Returns the number of elements in the dynamic array.
+
+        Runtime : O(1)
+        Space: O(1)
+
+        >>> arr = DynamicArray()
+        >>> arr.append(1)
+        >>> len(arr)
+        1
+        >>> arr.append(2)
+        >>> len(arr)
+        2
+        >>> arr.append(3)
+        >>> len(arr)
+        3
+        """
+        return self.size
+
+    def __str__(self) -> str:
+        """
+        Returns a string representation of the dynamic array.
+
+        >>> arr = DynamicArray()
+        >>> arr.append(1)
+        >>> arr.append(2)
+        >>> arr.append(3)
+        >>> str(arr)
+        '[1, 2, 3]'
+        >>> arr.append(4)
+        >>> str(arr)
+        '[1, 2, 3, 4]'
+        """
+        return "[" + ", ".join(str(self.array[i]) for i in range(self.size)) + "]"
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()

data_structures/arrays/gas_station.py

@@ -0,0 +1,50 @@
+from typing import NamedTuple
+
+
+class GasStation(NamedTuple):
+    gas: int  # Amount of gas available at this gas station
+    cost: int  # Cost of gas required to drive to the next station
+
+
+def can_complete_circuit(gas_stations: list[GasStation]) -> int:
+    """
+    Finds the starting station index to complete the circuit,
+    or returns -1 if not possible.
+    Args:
+      gas_stations (List[GasStation]): List of gas stations with gas and cost.
+    Returns:
+      The index of the starting station, or -1 if no solution exists.
+    Examples:
+    >>> GS = GasStation
+    >>> test_stations = (
+    ...     [GS(1, 3), GS(2, 4), GS(3, 5), GS(4, 1), GS(5, 2)],
+    ...     [GS(2, 3), GS(3, 4), GS(4, 3)],
+    ...     [GS(5, 4), GS(1, 4), GS(2, 1), GS(3, 5), GS(4, 1)]
+    ... )
+    >>> can_complete_circuit(test_stations[0])
+    3
+    >>> can_complete_circuit(test_stations[1])
+    -1
+    >>> can_complete_circuit(test_stations[2])
+    4
+    """
+    total_gas = sum(station.gas - station.cost for station in gas_stations)
+    current_gas: int = 0
+    start_station = 0
+    for i, gas_station in enumerate(gas_stations):
+        needed_gas = gas_station.gas - gas_station.cost
+        total_gas += needed_gas
+        current_gas += needed_gas
+        if current_gas < 0:
+            start_station = i + 1
+            current_gas = 0
+    if total_gas < 0:
+        return -1
+    return start_station
+
+
+# Example usage with doctests
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()