Leetcode

Linked List

• 2. Add Two Numbers
• 21. Merge Two Sorted Lists
• 23. Merge k Sorted Lists
• 25. Reverse Nodes in k-Group
• 92. Reverse Linked List II
• 138. Copy List with Random Pointer
• 146. LRU Cache
• 206. Reverse Linked List

Binary Tree

• Traverse Binary Tree Collection: 297, 105, 102, 103, 107, 144, 103, 987, 94, 145
• 95&96. Unique Binary Search Trees
• 98. Validate Binary Search Tree
• 105&106. Construct Binary Tree from Preorder and Inorder Traversal/Construct Binary Tree from Inorder and Postorder Traversal
• 112. Path Sum
• 114. Flatten Binary Tree to Linked List
• 116&117. Populating Next Right Pointers in Each Node I && II
• 236. Lowest Common Ancestor of a Binary Tree
• 1448. Count Good Nodes in Binary Tree

Binary Search Tree

Traverse BST

• 230&538&1038. BST inorder traverse

Operate BST

• 450. Delete Node in a BST
• 701. Insert into a Binary Search Tree

Dynamic Programming

• Knapsack Problems: 416, 518, 1049
• 5. Longest Palindromic Substring
• 10. Regular Expression Matching
• 42. Trapping Rain Water
• 53. Maximum Subarray
• 70. Climbing Stairs
• 72. Edit Distance
• 121. Best Time to Buy and Sell Stock
• 300. Longest Increasing Subsequence
• 322. Coin Change
• 583. Delete Operation for Two Strings
• 712. Minimum ASCII Delete Sum for Two Strings
• 931. Minimum Falling Path Sum
• 1143. Longest Common Subsequence

Divide And Conquer Method

• 347. Top K Frequent Elements

Graphics

Sorting

• 215. Kth Largest Element in an Array
• 973. K Closest Points to Origin

Two Pointers

• 3. Longest Substring Without Repeating Characters
• 11. Container With Most Water
• 15. 3Sum
• 75. Sort Colors
• 76. Minimum Window Substring
• 88. Merge Sorted Array
• 151. Reverse Words in a String
• 253. Meeting Rooms II

Backtracking

• 22. Generate Parentheses
• 46. Permutations
• 79. Permutations

Binary Search

• Binary Search Collection
• 4. Median of Two Sorted Arrays
• 33. Search in Rotated Sorted Array
• 34. Find First and Last Position of Element in Sorted Array
• 240. Search a 2D Matrix II
• 410. Split Array Largest Sum
• 875. Koko Eating Bananas
• 1011. Capacity To Ship Packages Within D Days

Others

• 1. Two Sum
• 6. Zigzag Conversion
• 7. Reverse Integer
• 20. Valid Parentheses
• 31. Next Permutation
• 48. Rotate Image
• 49. Group Anagrams
• 54. Spiral Matrix
• 56. Merge Intervals
• 59. Spiral Matrix II
• 200. Number of Islands
• 273. Integer to English Words
• 415. Add Strings & 43. Multiply Strings
• 440. K-th Smallest in Lexicographical Order
• 560. Subarray Sum Equals K
• 2850. Minimum Moves to Spread Stones Over Grid