LeetCode-Solutions
Leetcode Solutions Repository
A curated collection of Leetcode problem solutions in multiple programming languages including Python, C, C++, Java, and JavaScript. Explore, learn, and contribute to this ever-growing repository.
Introduction
Leetcode is a popular platform for practicing algorithmic problems, ranging from beginner to expert levels. This repository contains solutions to over 500 problems, organized by difficulty and category, with detailed explanations and clean, well-documented code.
Features
- 🧩 500+ Problems Solved: Solutions span various topics, including arrays, graphs, and dynamic programming.
- 💻 Multi-language Support: Available in Python, C, C++, Java, and JavaScript.
- 📖 Detailed Explanations: Each solution includes problem statements and step-by-step approaches.
- 🔄 Regular Updates: New problems and solutions are added consistently.
- 🌟 Open for Contributions: Join the community to enhance and expand this resource.
Solutions and Articles
You can explore the solutions in the table below. Each row includes:
- The problem number.
- The Leetcode problem title (linked to the problem page).
- A link to the corresponding Medium article for an in-depth explanation.
| Problem number | Leetcode Problem | Medium Article |
|---|---|---|
| 4 | Median of Two Sorted Arrays |  |
| 5 | Longest Palindromic Substring | |
| 17 | Letter Combinations of Phone Number | |
| 24 | Swap Nodes in Pairs | |
| 33 | Search in Rotated Sorted Array | |
| 34 | Find First and Last Position of Element in Sorted Array | |
| 46 | Permutations | |
| 50 | Pow(x,n) | |
| 54 | Spiral Matrix | |
| 59 | Spiral Matrix II | |
| 63 | Unique Paths II | |
| 68 | Text Justification | |
| 71 | Simplifying Path | |
| 74 | Search a 2D Matrix | |
| 77 | Combinations | |
| 81 | Search in Rotated Sorted Array II | |
| 86 | Partition List | |
| 92 | Reverse Linked List II | |
| 95 | Unique Binary Search Trees II | |
| 97 | Interleaving Strings | |
| 111 | Minimum Depth of a Binary Tree | |
| 118 | Pascal’s Triangle | |
| 119 | Pascal’s Triangle II | |
| 135 | Candy | |
| 137 | Single Number II | |
| 138 | Copy list with Random Pointer | |
| 139 | Word break | |
| 141 | Linked List Cycle | |
| 146 | LRU Cache | |
| 168 | Excel Sheet Column Title | |
| 207 | Course Schedule | |
| 209 | Minimum Size Subarray Sum | |
| 215 | Kth Largest element in an array | |
| 225 | Implement Stack using Queues | |
| 228 | Summary Ranges | |
| 239 | Sliding Window Maximum | |
| 258 | Add Digits | |
| 287 | Find the Duplicate Number | |
| 316 | Remove Duplicate Letters | |
| 319 | Bulb Switcher | |
| 332 | Reconstruct Itinerary | |
| 338 | Counting Bits | |
| 341 | Flatten Nested List Iterator | |
| 342 | Power of Four | |
| 343 | Integer Break | |
| 347 | Top K Frequent Elements | |
| 373 | Find K Pairs with Smallest Sums | |
| 389 | Find the Difference | |
| 392 | Is Subsequence | |
| 399 | Evaluate Division | |
| 403 | Frog Jump | |
| 435 | Non Overlapping Intervals | |
| 445 | Add two numbers II | |
| 459 | Repeated Substring Patterns | |
| 486 | Predict the Winner | |
| 501 | Find Mode in Binary Search Tree | |
| 515 | Find Largest Value in Each Tree Row | |
| 516 | Longest Palindromic Subsequence | |
| 518 | Coin Change II | |
| 530 | Minimum Absolute Difference in BST | |
| 542 | 01 Matrix | |
| 547 | Number of Provinices | |
| 646 | Maximum Length of a Pair Chain | |
| 649 | Dota2 Senate | |
| 662 | Maximum Width of Binary Tree | |
| 664 | Maximum Width of Binary Tree | |
| 673 | Number of Longest Increasing Sub-sequences | |
| 688 | Knight Probability in Chessboard | |
| 703 | Kth Largest element in a stream | |
| 705 | Design Hashset | |
| 706 | Design Hashmap | |
| 712 | Minimum ASCII Delete Sum for Two Strings | |
| 714 | Best Time to Buy and Sell Stock with Transaction Fee | |
| 725 | Split Linked List in Parts | |
| 735 | Asteroid Collision | |
| 744 | Find samllest letter greater than target | |
| 746 | Min Cost Climbing Stairs | |
| 758 | Is Graph Bipartite? | |
| 767 | Reorganize String | |
| 779 | K-th Symbol in Grammar | |
| 802 | Find Eventual Safe States | |
| 808 | Soup Servings | |
| 823 | Binary Tree with Factors | |
| 837 | New 21 Game | |
| 839 | Similar String Groups | |
| 844 | Backspace String Compare | |
| 852 | Peak Index in a Mountain Array | |
| 859 | Buddy Strings | |
| 863 | All Nodes Distance K in Binary Tree | |
| 864 | Shortest Path to Get All Keys | |
| 879 | Profitable Schemes | |
| 880 | Decoded String at Index | |
| 894 | All Possible Full Binary Trees | |
| 896 | Monotonic Array | |
| 920 | Number of Music Playlist | |
| 934 | Shortest Bridge | |
| 946 | Validate Stack Sequences | |
| 956 | Tallest Billboard | |
| 1027 | Longest Arithmetic Subsequence | |
| 1035 | Uncrossed Lines | |
| 1046 | Last Stone Weight | |
| 1091 | Shortest Path in Binary Matrix | |
| 1095 | Find in Mountain Array | |
| 1125 | Smallest Sufficient Team | |
| 1140 | Stone Game II | |
| 1146 | Snapshot Array | |
| 1161 | Maximum Level Sum of a Binary Tree | |
| 1187 | Make Array Strictly Increasing | |
| 1203 | Sort Items by Groups Respecting Dependencies | |
| 1218 | Longest Arithmetic Subsequence of Given Difference | |
| 1232 | Check If It Is a Straight Line | |
| 1282 | Group the People Given the Group Size They Belong To | |
| 1312 | Minimum Insertion Steps to Make a String Palindrome | |
| 1318 | Minimum Flips to Make a OR b Equal to c | |
| 1326 | Minimum Number of Taps to Open to Water a Garden | |
| 1337 | The K Weakest Rows in a Matrix | |
| 1351 | Count Negative Numbers in a Sorted Matrix | |
| 1361 | Validate Binary Tree Nodes | |
| 1372 | Longest ZigZag Path in a Binary Tree | |
| 1376 | Time needed to inform all employees | |
| 1396 | Design Underground System | |
| 1406 | Stone Game III | |
| 1416 | Restore The Array | |
| 1422 | Maximum Score After Splitting a String | |
| 1431 | Kids With the Greatest Number of Candies | |
| 1456 | Maximum Number of Vowels in a Substring of Given Length | |
| 1489 | Find Critical and Pseudo Critical Edges in Minimum Spanning Tree | |
| 1491 | Average Salary Excluding the Minimum and Maximum Salary | |
| 1493 | Longest Subarray of 1’s After Deleting One Element | |
| 1498 | Number of Subsequences That Satisfy the Given Sum Condition | |
| 1502 | Can Make Arithemetic Progressions from a Sequence | |
| 1512 | Number of Good Pairs | |
| 1514 | Path with Maximum Probability | |
| 1547 | Minimum Cost to cut a stick | |
| 1569 | Number of Ways to Reorder Array to Get Same BST | |
| 1572 | Matrix Diagonal Sum | |
| 1575 | Count All Possible Routes | |
| 1577 | Maximum number of vertices to Reach all nodes | |
| 1579 | Remove Max Number of Edges to Keep Graph Fully Traversable | |
| 1584 | Min Cost to Connect All Points | |
| 1601 | Maximum Number of Achievable Transfer Requests | |
| 1603 | Design Parking System | |
| 1615 | Maximal Network Rank | |
| 1639 | Number of Ways to Form a Target String Given a Dictionary | |
| 1647 | Minimum Deletions to Make Character Frequencies Unique | |
| 1658 | Minimum Operations to Reduce X to Zero | |
| 1697 | Checking the Existence of Edge Length Limited Paths | |
| 1721 | Swapping Nodes in a Linked List | |
| 1732 | Find the highest Altitude | |
| 1751 | Maximum Number of Events That Can Be Attended II | |
| 1768 | Merge Strings Alternately | |
| 1799 | Maximize score after N Operations | |
| 1802 | Maximum Value at a Given Index in a Bounded Array | |
| 1822 | Sign of the Product of an Array | |
| 1870 | Minimum Speed to Arrive on Time | |
| 1964 | Find the Longest Valid Obstacle Course at Each Position | |
| 1970 | Last Day Where You Can Still Cross | |
| 2009 | Minimum Number of Operations to Make Array Continuous | |
| 2022 | Convert 1D Array Into 2D Array | |
| 2028 | Find Missing Observation | |
| 2024 | Maximize the confusion of an Exam | |
| 2038 | Remove Colored Pieces if Both Neighbors are the same color | |
| 2050 | Parallel Courses III | |
| 2090 | K Radius Subarray Averages | |
| 2101 | Detonate the Maximum Bombs | |
| 2116 | Check if a Parantheses String Can Be a Valid | |
| 2130 | Maximum Twin sum of a Linked List | |
| 2140 | Solving Questions with Brainpower | |
| 2141 | Maximum Running time for N Computers | |
| 2215 | Find the Difference of Two Arrays | |
| 2218 | Maximum Value of K Coins From Piles | |
| 2251 | Number of Flowers in Full Bloom | |
| 2272 | Substring With Largest Variance | |
| 2305 | Fair Distribution of Cookies | |
| 2328 | Number of Increasing Paths in a Grid | |
| 2336 | Smallest Number in Infinite Set | |
| 2352 | Equal Row and Column Pairs | |
| 2366 | Minimum Replacements to Sort the Array | |
| 2369 | Check if there is a Valid Partition For The Array | |
| 2433 | Find The Original Array of Prefix Xor | |
| 2448 | Minimum Cost to Make Array Equal | |
| 2462 | Total Cost to Hire K Workers | |
| 2466 | Count Ways To Build Good Strings | |
| 2483 | Minimum Penalty for a shop | |
| 2542 | Maximum Subsequence Score | |
| 2551 | Put Marbles in Bags | |
| 2616 | Minimize the Maximum difference in pairs | |
| 2707 | Extra Characters in a String | |
Usage
This repository can serve multiple purposes:
- Reference: Find solutions to Leetcode problems with clean, readable code.
- Learning: Understand new problem-solving approaches and algorithmic techniques.
- Contribution: Collaborate to expand the repository with new solutions.
Contributing
Contributions are always welcome! Add new solutions, improve existing code, or enhance documentation. Before contributing, read the Contribution Guidelines.
License
This repository is licensed under the MIT License. Feel free to use, modify, and distribute the content as per the license terms.
Current Stats
- Rank: 83,730
- Total Problems Solved: 500+
Stay Updated
New solutions are added daily. Check back regularly for updates and stay connected!