I started solving questions on leetcode since Aug, 2018 and only listed the problems I solved twice. More questions will be updated for sure and they can be found at my github repository
Algorithm-and-Leetcode 1.Two Sum - 07 November 2018 10. Regular Expression Matching - 07 November 2018 100. Same Tree - 14 November 2018 101. Symmetric Tree - 14 November 2018 102. Binary Tree Level Order Traversal - 14 November 2018 103. Binary Tree Zigzag Level Order Traversal - 15 November 2018 104. Maximum Depth of Binary Tree - 15 November 2018 105. Construct Binary Tree from Preorder and Inorder Traversal - 19 November 2018 106. Construct Binary Tree from Inorder and Postorder Traversal - 16 November 2018 107. Binary Tree Level Order Traversal II - 16 November 2018 108. Convert Sorted Array to Binary Search Tree - 19 November 2018 109. Convert Sorted List to Binary Search Tree - 16 November 2018 11. Container With Most Water - 07 November 2018 110. Balanced Binary Tree - 19 November 2018 111. Minimum Depth of Binary Tree - 19 November 2018 112. Path Sum - 20 November 2018 113. Path Sum II - 20 November 2018 114. Flatten Binary Tree to Linked List - 21 November 2018 115. Distinct Subsequences - 21 November 2018 116. Populating Next Right Pointers in Each Node - 21 November 2018 117. Populating Next Right Pointers in Each Node II - 21 November 2018 118. Pascal's Triangle - 21 November 2018 119. Pascal's Triangle II - 22 November 2018 12. Integer to Roman - 07 November 2018 120. Triangle - 22 November 2018 121. Best Time to Buy and Sell Stock - 23 November 2018 122. Best Time to Buy and Sell Stock II - 23 November 2018 123. Best Time to Buy and Sell Stock III - 25 November 2018 124. Binary Tree Maximum Path Sum - 25 November 2018 125. Valid Palindrome - 25 November 2018 126. Word Ladder II - 19 March 2019 127. Word Ladder - 28 November 2018 128. Longest Consecutive Sequence - 28 November 2018 129. Sum Root to Leaf Numbers - 28 November 2018 13. Roman to Integer - 07 November 2018 130. Surrounded Regions - 28 November 2018 131. Palindrome Partitioning - 19 March 2019 132. Palindrome Partitioning II - 01 December 2018 133. Clone Graph - 01 December 2018 134. Gas Station - 03 December 2018 136. Single Number - 03 December 2018 137. Single Number II - 03 December 2018 138. Copy List with Random Pointer - 07 December 2018 139. Word Break - 07 December 2018 14. Longest Common Prefix - 07 November 2018 140. Word Break II - 07 December 2018 141. Linked List Cycle - 07 December 2018 142. Linked List Cycle II - 07 December 2018 143. Reorder List - 08 December 2018 144. Binary Tree Preorder Traversal - 08 December 2018 145. Binary Tree Postorder Traversal - 08 December 2018 146. LRU Cache - 07 May 2019 147. Insertion Sort List - 08 December 2018 148. Sort List - 13 December 2018 149. Max Points on a Line - 07 May 2019 15. 3Sum - 07 November 2018 150. Evaluate Reverse Polish Notation - 13 December 2018 151. Reverse Words in a String - 14 December 2018 152. Maximum Product Subarray - 16 December 2018 153. Find Minimum in Rotated Sorted Array - 16 December 2018 154. Find Minimum in Rotated Sorted Array II - 17 December 2018 155. Min Stack - 17 December 2018 157. Read N Characters Given Read4 - 07 May 2019 158. Read N Characters Given Read4 II - Call multiple times - 07 May 2019 16. 3Sum Closest - 07 November 2018 160. Intersection of Two Linked Lists - 17 December 2018 162. Find Peak Element - 18 December 2018 164. Maximum Gap - 18 December 2018 165. Compare Version Numbers - 18 December 2018 166. Fraction to Recurring Decimal - 20 December 2018 167. Two Sum II - Input array is sorted - 18 December 2018 168. Excel Sheet Column Title - 18 December 2018 169. Majority Element - 21 December 2018 17. Letter Combinations of a Phone Number - 07 November 2018 170. Two Sum III - Data structure design - 07 May 2019 171. Excel Sheet Column Number - 21 December 2018 172. Factorial Trailing Zeroes - 21 December 2018 173. Binary Search Tree Iterator - 21 December 2018 174. Dungeon Game - 07 May 2019 175. Combine Two Tables - 22 December 2018 176. Second Highest Salary - 23 December 2018 177. Nth Highest Salary - 22 December 2018 178. Rank Scores - 22 December 2018 179. Largest Number - 24 December 2018 18. 4Sum - 07 November 2018 180. Consecutive Numbers - 24 December 2018 181. Employees Earning More Than Their Managers - 21 December 2018 182. Duplicate Emails - 21 December 2018 183. Customers Who Never Order - 21 December 2018 184. Department Highest Salary - 21 December 2018 185. Department Top Three Salaries - 21 December 2018 187. Repeated DNA Sequences - 21 December 2018 189. Rotate Array - 06 January 2018 19. Remove Nth Node From End of List - 07 November 2018 190. Reverse Bits - 06 January 2018 191. Number of 1 Bits - 06 January 2018 198. House Robber - 06 January 2018 199. Binary Tree Right Side View - 06 January 2018 2. Add Two Numbers - 07 November 2018 20. Valid Parentheses - 07 November 2018 200. Number of Islands - 06 January 2018 201. Bitwise AND of Numbers Range - 07 January 2018 202. Happy Number - 07 January 2018 203. Remove Linked List Elements - 07 January 2019 204. Count Primes - 08 January 2019 205. Isomorphic Strings - 08 January 2019 206. Reverse Linked List - 08 January 2019 207. Course Schedule - 09 January 2019 208. Implement Trie (Prefix Tree) - 10 January 2019 209. Minimum Size Subarray Sum - 10 January 2019 21. Merge Two Sorted Lists - 07 November 2018 210. Course Schedule II - 10 January 2019 211. Add and Search Word - Data structure design - 10 January 2019 212. Word Search II - 10 January 2019 213. House Robber II - 15 January 2019 214. Shortest Palindrome - 15 January 2019 215. Kth Largest Element in an Array - 15 January 2019 216. Combination Sum III - 15 January 2019 217. Contains Duplicate - 15 January 2019 219. 496. Next Greater Element I - 08 May 2019 219. Contains Duplicate II - 19 January 2019 22. Generate Parentheses - 07 November 2018 220. Contains Duplicate III - 21 January 2019 221. Maximal Square - 22 January 2019 222. Count Complete Tree Nodes - 22 January 2019 223. Rectangle Area - 21 January 2019 224. Basic Calculator - 02 February 2019 225. Implement Stack using Queues - 02 February 2019 226. Invert Binary Tree - 04 February 2019 227. Basic Calculator II - 04 February 2019 228. Summary Ranges - 04 February 2019 229. Majority Element II - 09 February 2019 23. Merge k Sorted Lists - 07 November 2018 230. Kth Smallest Element in a BST - 09 February 2019 231. Power of Two - 09 February 2019 232. Implement Queue using Stacks - 10 February 2019 234. Palindrome Linked List - 10 February 2019 235. Lowest Common Ancestor of a Binary Search Tree - 10 February 2019 236. Lowest Common Ancestor of a Binary Tree - 12 February 2019 237. Delete Node in a Linked List - 12 February 2019 238. Product of Array Except Self - 12 February 2019 239. Sliding Window Maximum - 12 February 2019 24. Swap Nodes in Pairs - 07 November 2018 240. Search a 2D Matrix II - 12 February 2019 241. Different Ways to Add Parentheses - 12 February 2019 242. Valid Anagram - 16 February 2019 25. Reverse Nodes in k-Group - 07 November 2018 250. Count Univalue Subtrees - 10 May 2019 252. Meeting Rooms - 07 May 2019 253. Meeting Rooms II - 07 May 2019 257. Binary Tree Paths - 17 February 2019 258. Add Digits - 17 February 2019 26. Remove Duplicates from Sorted Array - 07 November 2018 261. Graph Valid Tree - 07 May 2019 263. Ugly Number - 21 February 2019 264. Ugly Number II - 21 February 2019 268. Missing Number - 21 February 2019 269. Alien Dictionary - 07 May 2019 27. Remove Element - 07 November 2018 270. Closest Binary Search Tree Value - 07 May 2019 273. Integer to English Words - 07 May 2019 274. H-Index - 22 February 2019 275. H-Index II - 22 February 2019 276. Paint Fence - 22 February 2019 277. Find the Celebrity - 07 May 2019 278. First Bad Version - 22 February 2019 279. Perfect Squares - 24 February 2019 28. Implement strStr() - 07 November 2018 280. Wiggle Sort - 24 February 2019 282. Expression Add Operators - 24 February 2019 283. Move Zeroes - 24 February 2019 284. Peeking Iterator - 24 February 2019 285. Inorder Successor in BST - 08 May 2019 285. Inorder Successor in BST - 08 May 2019 287. Find the Duplicate Number - 24 February 2019 289. Game of Life - 28 February 2019 29. Divide Two Integers - 07 November 2018 290. Word Pattern - 28 February 2019 292. Nim Game - 28 February 2019 295.Find Median from Data Stream - 28 February 2019 297. Serialize and Deserialize Binary Tree - 01 March 2019 299. Bulls and Cows - 01 March 2019 3. Longest Substring Without Repeating Characters - 07 November 2018 30. Substring with Concatenation of All Words - 07 November 2018 300. Longest Increasing Subsequence - 01 March 2019 301. Remove Invalid Parentheses - 03 March 2019 303. Range Sum Query - Immutable - 03 March 2019 304. Range Sum Query 2D - Immutable - 03 March 2019 305. Number Of Island II - 03 March 2019 306. Additive Number - 03 March 2019 307. Range Sum Query - Mutable - 04 March 2019 309. Best Time to Buy and Sell Stock with Cooldown - 04 March 2019 31. Next Permutation - 07 November 2018 310. Minimum Height Trees - 05 March 2019 312. Burst Balloons - 06 March 2019 313. Super Ugly Number - 06 March 2019 314. Binary Tree Vertical Order Traversal - 08 May 2019 315. Count of Smaller Numbers After Self - 06 March 2019 316. Remove Duplicate Letters - 13 May 2019 318. Maximum Product of Word Lengths - 08 May 2019 319. Bulb Switcher - 08 May 2019 32. Longest Valid Parentheses - 07 November 2018 322. Coin Change - 08 May 2019 324. Wiggle Sort II - 08 May 2019 325. Maximum Size Subarray Sum Equals k - 08 May 2019 328. Odd Even Linked List - 08 May 2019 329. Longest Increasing Path in a Matrix - 08 May 2019 33. Search in Rotated Sorted Array - 07 November 2018 331. Verify Preorder Serialization of a Binary Tree - 08 May 2019 332. Reconstruct Itinerary - 08 May 2019 334. Increasing Triplet Subsequence - 08 May 2019 336. Palindrome Pairs - 08 May 2019 337. House Robber III - 08 May 2019 338. Counting Bits - 08 May 2019 339. Nested List Weight Sum - 08 May 2019 34. Find First and Last Position of Element in Sorted Array - 07 November 2018 340. Longest Substring with At Most K Distinct Characters - 09 May 2019 341. Flatten Nested List Iterator - 08 May 2019 342. Power of Four - 08 May 2019 343. Integer Break - 08 May 2019 344. Reverse String - 08 May 2019 345. Reverse Vowels of a String - 08 May 2019 346. Moving Average from Data Stream - 08 May 2019 347. Top K Frequent Elements - 08 May 2019 348. Design Tic-Tac-Toe - 08 May 2019 349. Intersection of Two Arrays - 08 May 2019 35. Search Insert Position - 07 November 2018 350. Intersection of Two Arrays II - 08 May 2019 355. Design Twitter - 08 May 2019 357. Count Numbers with Unique Digits - 08 May 2019 36. Valid Sudoku - 07 November 2018 360. Sort Transfromed Array - 08 May 2019 362. Design Hit Counter - 08 May 2019 364. Nested List Weight Sum II - 08 May 2019 37. Sudoku Solver - 07 November 2018 377. Combination Sum IV - 08 May 2019 378. Kth Smallest Element in a Sorted Matrix - 08 May 2019 38. Count and Say - 07 November 2018 380. Insert Delete GetRandom O(1) - 08 May 2019 382. Linked List Random Node - 10 May 2019 382. Linked List Random Node - 13 May 2019 387. First Unique Character in a String - 08 May 2019 39. Combination Sum - 07 November 2018 392. Is Subsequence - 08 May 2019 393. UTF-8 Validation - 08 May 2019 394. Decode String - 08 May 2019 395. Longest Substring with At Least K Repeating Characters - 08 May 2019 399. Evaluate Division - 08 May 2019 4. Median of Two Sorted Arrays - 07 November 2018 40. Combination Sum II - 07 November 2018 41. First Missing Positive - 07 November 2018 410. Split Array Largest Sum - 08 May 2019 412. Fizz Buzz - 08 May 2019 416. Partition Equal Subset Sum - 08 May 2019 42. Trapping Rain Water - 07 November 2018 426. Convert Binary Search Tree to Sorted Doubly Linked List - 09 May 2019 427. Construct Quad Tree - 10 May 2019 429. N-ary Tree Level Order Traversal - 08 May 2019 43. Multiply Strings - 07 November 2018 435. Non-overlapping Intervals - 08 May 2019 437. Path Sum III - 08 May 2019 438. Find All Anagrams in a String - 08 May 2019 44. Wildcard Matching - 07 November 2018 443. String Compression - 08 May 2019 445. Add Two Numbers II - 08 May 2019 448. Find All Numbers Disappeared in an Array - 10 May 2019 449. Serialize and Deserialize BST - 08 May 2019 45. Jump Game II - 07 November 2018 450. Delete Node in a BST - 08 May 2019 452. Minimum Number of Arrows to Burst Balloons - 08 May 2019 458. Poor Pigs - 10 May 2019 458. Poor Pigs - 13 May 2019 46. Permutations - 07 November 2018 460. LFU Cache - 08 May 2019 468. Validate IP Address - 08 May 2019 47. Permutations II - 07 November 2018 48. Rotate Image - 07 November 2018 489. Robot Room Cleaner - 08 May 2019 49. Group Anagrams - 07 November 2018 490. The Maze - 08 May 2019 494. Target Sum - 08 May 2019 5. Longest Palindromic Substring - 07 November 2018 50. Pow(x, n) - 07 November 2018 501. Find Mode in Binary Search Tree - 08 May 2019 503. Next Greater Element II - 08 May 2019 505. The Maze II - 08 May 2019 508. Most Frequent Subtree Sum - 08 May 2019 509. Fibonacci Number - 09 May 2019 51. N-Queens - 07 November 2018 518. Coin Change 2 - 10 May 2019 52. N-Queens II - 07 November 2018 528. Random Pick with Weight - 08 May 2019 529. Minesweeper - 08 May 2019 53. Maximum Subarray - 07 November 2018 530. Minimum Absolute Difference in BST - 08 May 2019 535. Encode and Decode TinyURL - 08 May 2019 54. Spiral Matrix - 07 November 2018 542. 01 Matrix - 19 March 2019 543. Diameter of Binary Tree - 08 May 2019 546. Remove Boxes - 23 March 2019 547. Friend Circles - 08 May 2019 55. Jump Game - 07 November 2018 56. Merge Intervals - 07 November 2018 564. Find the Closest Palindrome - 09 May 2019 57. Insert Interval - 07 November 2018 572. Subtree of Another Tree - 08 May 2019 576. Out of Boundary Paths - 23 March 2019 58. Length of Last Word - 07 November 2018 583. Delete Operation for Two Strings - 08 May 2019 589. N-ary Tree Preorder Traversal - 08 May 2019 59. Spiral Matrix II - 07 November 2018 590. N-ary Tree Postorder Traversal - 08 May 2019 6. ZigZag Conversion - 07 November 2018 60. Permutation Sequence - 07 November 2018 609. Find Duplicate File in System - 08 May 2019 61. Rotate List - 07 November 2018 617. Merge Two Binary Trees - 08 May 2019 62. Unique Paths - 07 November 2018 621. Task Scheduler - 08 May 2019 63. Unique Paths II - 07 November 2018 635. Design Log Storage System - 13 May 2019 636. Exclusive Time of Functions - 09 May 2019 637. Average of Levels in Binary Tree - 08 May 2019 64. Minimum Path Sum - 07 November 2018 642. Design Search Autocomplete System - 08 May 2019 647. Palindromic Substrings - 08 May 2019 648. Replace Words - 07 March 2019 65. Valid Number - 07 November 2018 653. Two Sum IV - Input is a BST - 08 May 2019 654. Maximum Binary Tree - 08 May 2019 66. Plus One - 07 November 2018 664. Strange Printer - 08 May 2019 668. Kth Smallest Number in Multiplication Table - 08 May 2019 669. Trim a Binary Search Tree - 08 May 2019 67. Add Binary - 07 November 2018 673. Number of Longest Increasing Subsequence - 08 May 2019 675. Cut Off Trees for Golf Event - 19 March 2019 676. Implement Magic Dictionary - 07 March 2019 677. Map Sum Pairs - 07 March 2019 679. 24 Game - 09 May 2019 68. Text Justification - 08 May 2019 683. K Empty Slots - 08 May 2019 684. Redundant Connection - 08 May 2019 685. Redundant Connection II - 08 May 2019 687. Longest Univalue Path - 08 May 2019 688. Knight Probability in Chessboard - 23 March 2019 69. Sqrt(x) - 07 November 2018 692. Top K Frequent Words - 08 May 2019 695. Max Area of Island - 08 May 2019 698. Partition to K Equal Sum Subsets - 19 March 2019 7. Reverse Integer - 07 November 2018 70. Climbing Stairs - 07 November 2018 700. Search in a Binary Search Tree - 08 May 2019 701. Insert into a Binary Search Tree - 08 May 2019 704. Binary Search - 08 May 2019 706. Design HashMap - 08 May 2019 707. Design Linked List - 08 May 2019 71. Simplify Path - 07 November 2018 710. Random Pick with Blacklist - 08 May 2019 712. Minimum ASCII Delete Sum for Two Strings - 08 May 2019 716. Max Stack - 08 May 2019 717. 1-bit and 2-bit Characters - 08 May 2019 719. Find K-th Smallest Pair Distance - 08 May 2019 72. Edit Distance - 07 November 2018 720. Longest Word in Dictionary - 08 March 2019 721. Accounts Merge - 08 May 2019 726. Number of Atoms - 08 May 2019 729. My Calendar I - 08 May 2019 73. Set Matrix Zeroes - 07 November 2018 731. My Calendar II - 08 May 2019 733. Flood Fill - 08 May 2019 735. Asteroid Collision - 08 May 2019 74. Search a 2D Matrix - 07 November 2018 740. Delete and Earn - 08 May 2019 741. Cherry Pickup - 08 May 2019 743. Network Delay Time - 08 May 2019 745. Prefix and Suffix Search - 08 March 2019 746. Min Cost Climbing Stairs - 08 May 2019 75. Sort Colors - 07 November 2018 752. Open the Lock - 19 March 2019 753. Cracking the Safe - 09 May 2019 755. Pour Water - 08 May 2019 759. Employee Free Time - 08 May 2019 76. Minimum Window Substring - 07 November 2018 763. Partition Labels - 08 May 2019 77. Combinations - 07 November 2018 771. Jewels and Stones - 08 May 2019 772. Basic Calculator III - 08 May 2019 773. Sliding Puzzle - 09 May 2019 778. Swim in Rising Water - 08 May 2019 78. Subsets - 07 November 2018 784. Letter Case Permutation - 11 March 2019 784. Letter Case Permutation - 19 March 2019 785. Is Graph Bipartite? - 08 May 2019 786. K-th Smallest Prime Fraction - 08 May 2019 788. Rotated Digits - 08 May 2019 79. Word Search - 07 November 2018 790. Domino and Tromino Tiling - 08 May 2019 792. Number of Matching Subsequences - 08 May 2019 8. String to Integer (atoi) - 07 November 2018 80. Remove Duplicates from Sorted Array II - 07 November 2018 801. Minimum Swaps To Make Sequences Increasing - 08 May 2019 802. Find Eventual Safe States - 08 May 2019 81. Search in Rotated Sorted Array II - 07 November 2018 811. Subdomain Visit Count - 08 May 2019 813. Largest Sum of Averages - 08 May 2019 814. Binary Tree Pruning - 08 May 2019 815. Bus Routes - 08 May 2019 818. Race Car - 08 May 2019 819. Most Common Word - 08 May 2019 82. Remove Duplicates from Sorted List II - 07 November 2018 827. Making A Large Island - 08 May 2019 83. Remove Duplicates from Sorted List - 07 November 2018 833. Find And Replace in String - 08 May 2019 836. Rectangle Overlap - 08 May 2019 839. Similar String Groups - 08 May 2019 84. Largest Rectangle in Histogram - 07 November 2018 841. Keys and Rooms - 08 May 2019 842. Split Array into Fibonacci Sequence - 19 March 2019 843. Guess the Word - 08 May 2019 844. Backspace String Compare - 08 May 2019 847. Shortest Path Visiting All Nodes - 08 May 2019 85. Maximal Rectangle - 05 March 2019 850. Rectangle Area II - 08 May 2019 852. Peak Index in a Mountain Array - 08 May 2019 856. Score of Parentheses - 08 May 2019 86. Partition List - 07 November 2018 864. Shortest Path to Get All Keys - 08 May 2019 872. Leaf-Similar Trees - 08 May 2019 875. Koko Eating Bananas - 08 May 2019 88. Merge Sorted Array - 07 November 2018 886. Possible Bipartition - 08 May 2019 89. Gray Code - 13 November 2018 9. Palindrome Number - 07 November 2018 90. Subsets II - 13 November 2018 901. Online Stock Span - 08 March 2019 904. Fruit Into Baskets - 08 May 2019 907. Sum of Subarray Minimums - 08 March 2019 91. Decode Ways - 13 November 2018 92. Reverse Linked List II - 13 November 2018 923. 3Sum With Multiplicity - 08 May 2019 924. Minimize Malware Spread - 08 May 2019 929. Unique Email Addresses - 08 May 2019 93. Restore IP Addresses - 19 March 2019 931. Minimum Falling Path Sum - 23 March 2019 933. Number of Recent Calls - 08 May 2019 934. Shortest Bridge - 19 March 2019 935. Knight Dialer - 23 March 2019 937. Reorder Log Files - 08 May 2019 939. Minimum Area Rectangle - 08 May 2019 94. Binary Tree Inorder Traversal - 13 November 2018 943. Find the Shortest Superstring - 11 March 2019 947. Most Stones Removed with Same Row or Column - 08 May 2019 95. Unique Binary Search Trees II - 13 November 2018 952. Largest Component Size by Common Factor - 08 May 2019 957. Prison Cells After N Days - 08 May 2019 959. Regions Cut By Slashes - 08 May 2019 96. Unique Binary Search Trees - 14 November 2018 965. Univalued Binary Tree - 08 May 2019 968. Binary Tree Cameras - 08 May 2019 97. Interleaving String - 05 March 2019 973. K Closest Points to Origin - 08 May 2019 975. Odd Even Jump - 08 May 2019 977. Squares of a Sorted Array - 08 May 2019 979. Distribute Coins in Binary Tree - 08 May 2019 98. Validate Binary Search Tree - 14 November 2018 980. Unique Paths III - 23 March 2019 981. Time Based Key-Value Store - 08 May 2019 986. Interval List Intersections - 08 May 2019 987. Vertical Order Traversal of a Binary Tree - 08 May 2019 990. Satisfiability of Equality Equations - 08 May 2019 996. Number of Squareful Arrays - 23 March 2019