tianhao-li/leetcode

Leetcode practice record

Leetcode

This is my Leetcode practice record.

Questions Need Attention

230. Kth Smallest Element in a BST -- Follow ups, involves Greater Tree and AVL Tree.

LRU Cache

212 Word Search 2

28. Implement strStr() -- Optimized solutions: (1) Rabin-Karp (2) KMP

Solved Problems

Design

380. Insert Delete GetRandom O(1)

146. LRU Cache

DP

322 & 279 closely related

62. Unique Paths

121. Best Time to Buy and Sell Stock

122. Best Time to Buy and Sell Stock II

123. Best Time to Buy and Sell Stock III

139. Word Break

279. Perfect Squares

322. Coin Change

718. Maximum Length of Repeated Subarray

730. Count Different Palindromic Subsequences

2016. Maximum Difference Between Increasing Elements

Graph

277. Find the Celebrity

329. Longest Increasing Path in a Matrix

DFS

79. Word Search

104. Maximum Depth of Binary Tree

130. Surrounded Regions

200. Number of Islands

341. Flatten Nested List Iterator

Binary Search

153. Find Minimum in Rotated Sorted Array

719. Find K-th Smallest Pair Distance

Two Pointers

19. Remove Nth Node From End of List

75. Sort Colors

76. Minimum Window Substring

160. Intersection of Two Linked Lists

202. Happy Number

253. Meeting Rooms II

287. Find the Duplicate Number

295. Find Median from Data Stream

719. Find K-th Smallest Pair Distance

1209. Remove All Adjacent Duplicates in String II

Tree

116. Populating Next Right Pointers in Each Node

230. Kth Smallest Element in a BST

285. Inorder Successor in BST

HashMap

1. Two Sum

36. Valid Sudoku

49. Group Anagrams

380. Insert Delete GetRandom O(1)

2225. Find Players With Zero or One Losses

String

13. Roman to Integer

28. Implement strStr()

68. Text Justification

224. Basic Calculator

696. Count Binary Substrings

811. Subdomain Visit Count

1328. Break a Palindrome

Array

41. First Missing Positive

56. Merge Intervals

57. Insert Interval

73. Set Matrix Zeroes

350. Intersection of Two Arrays II

945. Minimum Increment to Make Array Unique

1010. Pairs of Songs With Total Durations Divisible by 60

Linked List

146. LRU Cache

328. Odd Even Linked List

1836. Remove Duplicates From an Unsorted Linked List

Math

780. Reaching Points