Solving Data Structure and Algorithm Problems on LeetCode Using C++

This repository contains 🌟 solutions to various data structure and algorithm problems from LeetCode. All solutions are implemented in C++ and are structured for easy understanding and reusability.

🗂️ Repository Structure

• 📂 Each solution is stored in a separate C++ file, named according to the problem number and title.
• 🏷️ Organized by category: Arrays, Strings, Trees, Graphs, and more.

Directory Layout

📂 .
├── 📁 depth-first-search
│   ├── 📁 easy
│   │   ├── 112.path_sum.cpp
│   │   ├── 257.binary_tree_paths.cpp
│   │   └── 543.diameter_of_binary_tree.cpp
│   ├── 📁 hard
│   │   └── 124.binary_tree_maximum_path_sum.cpp
│   ├── 📁 medium
│   │   ├── 113.path_sum_ii.cpp
│   │   ├── 129.sum_root_to_leaf_numbers.cpp
│   │   ├── 1430.check_if_a_string_is_a_valid_sequence_from_root_to_leaves_path.cpp
│   │   └── 437.path_sum_iii.cpp
├── 📁 design
│   ├── 📁 easy
│   │   ├── 225.implement_stack_using_queues.cpp
│   │   └── 232.implement_queue_using_stacks.cpp
│   ├── 📁 medium
│   │   └── 146.lru_cache.cpp
├── 📁 dynamic-programming
│   ├── 📁 easy
│   │   └── 509.fibonacci_number.cpp
├── 📁 heap-priority-queue
│   ├── 📁 hard
│   │   └── 295.find_median_from_data_stream.cpp
├── 📁 linked-list
│   ├── 📁 easy
│   │   ├── 206.reverse_linked_list.cpp
│   │   ├── 21.merge_two_sorted_lists.cpp
│   │   └── 83.remove_duplicates_from_sorted_list.cpp
│   ├── 📁 medium
│   │   ├── 24.swap_nodes_in_pairs.cpp
│   │   ├── 82.remove_duplicates_from_sorted_list_ii.cpp
│   │   └── 92.reverse_linked_list_ii.cpp
├── 📁 matrix
│   ├── 📁 easy
│   │   ├── 463.island_perimeter.cpp
│   │   └── 733.flood_fill.cpp
│   ├── 📁 medium
│   │   ├── 1254.number_of_closed_islands.cpp
│   │   ├── 1559.detect_cycles_in_2d_grid.cpp
│   │   ├── 200.number_of_islands.cpp
│   │   ├── 694.number_of_distinct_islands.cpp
│   │   └── 695.max_area_of_island.cpp
├── 📁 prefix-sum
│   ├── 📁 easy
│   │   └── 303.range_sum_query_immutable.cpp
├── 📁 stack
│   ├── 📁 medium
│   │   └── 155.min_stack.cpp
├── LICENSE
├── README.md
├── directory_layout_script.py
├── problem_description_script.py
└── requirements.txt

💡 Pro Tip: Click the filenames to view each solution directly on GitHub!

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🔑 Problem Categories

📂 Category	📜 Description
📊 Arrays	Searching, sorting, subarray sums, and more.
🧵 Strings	String manipulations, substrings, and pattern matching.
🔗 Linked Lists	Singly, doubly linked list problems.
🌲 Trees	Binary trees, search trees, and n-ary trees.
🗺️ Graphs	Traversals, shortest paths, and connectivity.
🚀 Dynamic Programming	Optimal substructure and overlapping subproblems.

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🛠️ Solution Format

Each solution file contains:

1. Problem Description: A detailed explanation of the problem, its constraints, and examples.
2. Test Cases: Example inputs and expected outputs.
3. Python Implementation: The function or class implementing the solution.
4. Time and Space Complexity Analysis: A brief analysis of the efficiency of the solution.