awesome leetcode resources

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This repository contains awesome LeetCode resources to learn Data Structures and Algorithms (DSA) and prepare for Coding interviews.

Tips

• How to Start LeetCode
• How I Mastered DSA

? Fundamental Concepts

• Algorithmic Complexity
• Big-O Cheat Sheet
• Bit Manipulation Techniques
• Sorting Algorithms
• Linked List
  • Dummy Node Technique
• Queues
• Stacks
• Hash Tables
• Heaps
• Recursion
• Backtracking
• Trees
• Tries
• Binary Search
• Greedy Algorithm
• Dynamic Programming
• Graph Theory
• Important Graph Algorithms
• DFS Traversal
• BFS Traversal
• Union-Find
• Dijkstra Algorithm
• Minimum Spanning Tree

Patterns

• 15 Leetcode Patterns
• 20 DP Patterns
• Prefix Sum Pattern
• Top 'K' Elements Pattern
• Fast and Slow Pointers Pattern
• Two Pointers Pattern
• Linked List In-place Reversal Pattern
• Sliding Window Pattern
• Monotonic Stack Pattern
• Overlapping Intervals Pattern
• Backtracking Pattern
• Modified Binary Search Pattern
• Tree Patterns
  • Tree Iterative Traversal
  • Tree Question Pattern
• Graph Patterns
• DFS + BFS Patterns (1)
• DFS + BFS Patterns (2)

Must-Read Leetcode Articles

• Sliding Window Template
• Two Pointers Patterns
• Collections of Important String Questions
• Substring Problem Template
• Binary Search Template
• A General Approach to Backtracking Questions
• Monotonic Stack Template
• Heap Patterns
• Bit Manipulation Patterns
• Dynamic Programming Patterns
• Stock Series Patterns

YouTube Playlist

• Abdul Bari's Algorithms Playlist
• William Fiset's Data Structure Playlist
• William Fiset's Graphs Playlist
• Tushar Roy's Dynamic Programming Playlist

? Courses

• Coursera - Algorithms, Part I
• Coursera - Algorithms, Part 2

Books

• Data Structures And Algorithms Made Easy
• Cracking the Coding Interview

? Visualization

• VisuAlgo
• Algo-lens: Visualize leetcode problems

? LeetCode Extensions

• LeetCode Timer: Easily time your leetcode practise sessions with automatic time setting based on difficulty.
• LeetCode Video Solutions: Watch free LeetCode video ▶ solutions on the problem page itself.
• LeetCode Format: Adds Format code button on leetcode to format the code using Prettier code formatter.
• LeetHub v2: Automatically integrate your Leetcode & GeeksforGeeks submissions to GitHub.
• LeetCode VS Code Extension: Solve LeetCode problems in VS Code.

✅ Curated Problems

• Blind 75
• Leetcode Top 100 Liked
• Leetcode Top Interview 150

Must-Do Problems (Topic Wise)

Linked List

• Reverse Linked List
• Linked List Cycle
• Merge Two Sorted Lists
• Intersection of Two Linked Lists
• Remove Nth Node From End of List
• Add Two Numbers
• Copy List with Random Pointer
• Flatten a Multilevel Doubly Linked List
• Rotate List
• Sort List
• Remove Duplicates from Sorted List II
• LRU Cache
• Design Browser History
• Merge k Sorted Lists
• Reverse Nodes in k-Group

Binary Trees

• Invert Binary Tree
• Convert Sorted Array to Binary Search Tree
• Count Complete Tree Nodes
• All Possible Full Binary Trees
• Delete Leaves With a Given Value
• Binary Search Tree Iterator
• Longest Univalue Path
• Delete Nodes And Return Forest
• Validate Binary Search Tree
• Construct Binary Tree from Inorder and Postorder Traversal
• All Nodes Distance K in Binary Tree
• Maximum Difference Between Node and Ancestor
• Find Duplicate Subtrees
• Flatten Binary Tree to Linked List
• House Robber III
• Step-By-Step Directions From a Binary Tree Node to Another
• Delete Node in a BST
• Populating Next Right Pointers in Each Node II
• Trim a Binary Search Tree
• Distribute Coins in Binary Tree
• Binary Search Tree to Greater Sum Tree
• Serialize and Deserialize Binary Tree
• Binary Tree Cameras
• Binary Tree Maximum Path Sum
• Maximum Sum BST in Binary Tree

Backtracking

• Permutations
• Subsets
• Generate Parentheses
• Combination Sum
• Palindrome Partitioning
• Letter Combinations of a Phone Number
• Unique Binary Search Trees II
• Partition to K Equal Sum Subsets
• N-Queens II
• Sudoku Solver

Tries

• Implement Trie (Prefix Tree)
• Longest Common Prefix
• Search Suggestions System
• Longest Word in Dictionary
• Top K Frequent Words
• Design Add and Search Words Data Structure
• Implement Magic Dictionary
• Replace Words
• Word Search II
• Stream of Characters

Your contributions are most welcome!