LeetCode

我的LeetCode刷题、思路和代码总结, 以Top 100 liked & Top interviewed questions 为主（since 2020, 更新中）.

部分题目待更新，题解将逐步完善.

Tag

题目列表

Two Pointers

• Pair with Target Sum (模板)
• Remove Duplicates (模板)
• Triplet Sum to Zero (模板)
  • Follow up: Triplet Sum Close to Target
• Subarrays with Product Less than a Target (medium)
• Dutch National Flag Problem (medium) / 三色旗 / 颜色分类
• 4Sum
• 1537. Get the Maximum Score (Hard)
• 42. Trapping Rain Water

DP

• 10. Regular Expression Matching 字符匹配
• 45. Jump Game 2
• 198. House Robber
• 337. House Robber III
• 256. Paint House
• 265. Paint House 2 (Hard)
• 221. Maximal Square (Medium)
• 494. Target Sum (Medium)
• 746. Min Cost Climbing Stairs
• 279. Perfect Squares
• 63. Unique Paths
• 322. Coin Change
• 518. Coin Change 2
• 486. Predict the Winner
• 377. Combination Sum IV
• 131. Palindrome Partitioning 最长回文串划分
• 516. Longest Palindromic Subsequence 最长回文串子序列个数
• 139. Word Break
• 1524. Number of Sub-arrays With Odd Sum

Tree

• 96. Unique Binary Search Tree
• 95. Unique Binary Search Trees II
• 98. Validate a BST
• 99. Recover Binary Search Tree (Hard)
• 100. Same Tree (easy)
• 101. Symmetric Tree (easy)
• 111. Minimum Depth of Binary Tree
• 105. Construct Binary Tree from Preorder and Inorder Traversal
• 108. Convert Sorted Array to Binary Search Tree (Easy)
• 107. 层序遍历
• 112. Path Sum
• 113. Path Sum II
• 116. Populating Next Right Pointers in Each Node
• 437. Path Sum III (easy)
• 124. Binary Tree Maximum Path Sum
• 306. Find Leaves of Binary Tree
• 701. Insert into a BST
• 572. Subtree of Another Tree

Linked List

• 19. Remove Nth Node From End of List
• 24. Swap Nodes in Pair
• 141. Linked List Cycle
• 160. Intersection of Two Linked Lists
• 109. Convert Sorted List to BST
• 206. Reverse Linked List (经典 每日一题)
• 25. Reverse Node in k-Group (经典 Hard)
• 92. Reverse Linked List II (经典)
• 328. Odd Even Linked List

Depth-First-Search

• 79. Word Search
• 130. Surrounded Regions
• 200. Numbers of Islands (三种方法, 经典)
• 694. Number of Distinct Islands
• 695. Max Area of Island
• 547. Friend Circles
• 733. Flood Fill (经典)
• 967. Numbers With Same Consecutive Differences

Breath-First-Search

• 207. Course Schedule (经典)

• 210. Course Schedule II (经典)

• 994. Rotting Oranges

Graph

• 207. Course Schedule (经典)
• 210. Course Schedule II (经典)
• 399. Evaluate Division (Graph + BFS)
• 269. Alien Dictionary (Graph + BFS)
• 1192. Critical Connections in a Network (Hard)
• 277. Find the Celebrity
• 863. All Nodes Distance K in Binary Tree

Binary Search

• 162. Find Peak Element
• 4. Median of Two Sorted Arrays (Hard)
• 729. My Calendar I
• 33. Search in Rotated Sorted Array
• 34. Find First and Last Position of Element in Sorted Array
• 74. Search a 2D Matrix
• 153. Find Minimum in Rotated Sorted Array
• 209. Minimum Size Subarray Sum
• 230. Kth Smallest Element in a BST
• 240. Search a 2D Matrix II
• 270. Closest Binary Search Tree Value
• 287. Find the Duplicate Number
• 300. Longest Increasing Subsequence
• 315. Count of Smaller Numbers After Self
• 374. Guess Number Higher or Lower
• 875. Koko Eating Bananas
• 1283. Find the Smallest Divisor Given a Threshold
• 1337. The K Weakest Rows in a Matrix
• 1351. Count Negative Numbers in a Sorted Matrix

Sliding Window

• 3. Longest Substring Without Repeating Characters

• 76. Minimum Window Substring

• 30. Substring with Concatenation of All Words

• 模板题：String Anagrams (hard)

• 模板题：Permutation in a String (hard)

Merge Intervals

• 模板题: Merge Intervals (合并区间)
• 模板题: Insert Interval (插入区间)
• 模板题: Intervals Intersection (查找交集)
• 模板题: Conflicting Appointments (冲突区间)
• 模板题: Minimum Meeting Rooms (最少的会议室)
• Maximum CPU Load
• Employee Free Time (Hard)
• 729. My Calendar I
• 435. Non-overlapping Intervals (Greedy Method)

Subset

• 78. Subsets
• 90. Subsets II

BackTracking

• 17. Letter Combinations of a Phone Number
• 22. Generate Parentheses
• 51. N皇后问题
• 46. Permutation
• 47. Permutations II

Stack

• 84. Largest Rectangle in Histogram 直方图最大面积
• 232. Implement Queue using Stacks 利用栈实现队列

Heap / Heap Sort

• 973. K Closest Points to Origin (Medium)
• 378. Kth Smallest Element in a Sorted Matrix
• 295. Find Median from Data Stream (Hard)

Design

• 146. LRU Cache (每日一题)
• 380. Insert Delete GetRandom O(1) (每日一题)
• 208. Implement Trie (Prefix Tree)
• 212. Word Search II
• 211. Add and Search Word - Data structure design
• 1286. Iterator for Combination (Google)
• 1032. Stream of Characters (Use Trie)

Array

• 238. Product of Array Except Self
• 179. Largest Number
• 498. Diagonal Traverse
• 334. Increasing Triplet Subsequence
• 442. Find All Duplicates in an Array
• 406. Queue Reconstruction by Height

String

• 10. Regular Expression Matching 字符匹配
• 32. Longest Valid Parentheses (经典)
• 38. Count and Say
• 44. Wildcard Matching 万卡匹配
• 929. Unique Email Addresses
• 1041. Robot Bounded In Circle
• 763. Partition Labels
• 1505. Minimum Possible Integer After at Most K Adjacent Swaps On Digits

Palindrome

• 5. Longest Palindromic Substring (经典)

• 131. Palindrome Partitioning

• 214. Shortest Palindrome (Hard)

• 234. Palindrome Linked List (Easy)

• 266. Palindrome Permutation (Easy)

• 336.Palindrome Pairs (Hard, Amazon)

• 409. Longest Palindrome

• 516. Longest Palindromic Subsequence