(Notes: "♥" means you need to buy a book from Leetcode)
| # | Title | Difficulty | Topics | Solution |
|---|---|---|---|---|
| 1 | Two Sum | Easy | Array, Hash Table | golang |
| 2 | Add Two Numbers | Medium | Linked List, Math | golang |
| 3 | Longest Substring Without Repeating Characters | Medium | Hash Table, Two Pointers, String, Sliding Window | golang, c |
| 4 | Median of Two Sorted Arrays | Hard | Array, Binary Search, Divide and Conquer | golang |
| 5 | Longest Palindromic Substring | Medium | String, Dynamic Programming | golang |
| 6 | ZigZag Conversion | Medium | String | golang |
| 7 | Reverse Integer | Easy | Math | golang, c |
| 8 | String to Integer (atoi) | Medium | Math, String | golang |
| 10 | Regular Expression Matching | Hard | String,Dynamic Programming,Backtracking | golang |
| 12 | Integer to Roman | Medium | Math, String | golang |
| 13 | Roman to Integer | Easy | Math, String | golang |
| 17 | Letter Combinations of a Phone Number | Medium | String, Backtracking | golang |
| 29 | Divide Two Integers | Medium | Math, Binary Search | golang |
| 39 | Combination Sum | Medium | Array, Backtracking | golang |
| 40 | Combination Sum II | Medium | Array, Backtracking | golang |
| 43 | Multiply Strings | Medium | Math, String | golang |
| 45 | Jump Game II | Hard | Array, Greedy | golang |
| 46 | Permutations | Medium | Backtracking | golang |
| 47 | Permutations II | Medium | Backtracking | golang |
| 50 | Pow(x, n) | Medium | Math, Binary Search | golang |
| 54 | Spiral Matrix | Medium | Array | golang |
| 55 | Jump Game | Medium | Array, Greedy | golang |
| 59 | Spiral Matrix II | Medium | Array | golang |
| 62 | Unique Paths | Medium | Array, Dynamic Programming | golang |
| 63 | Unique Paths II | Medium | Array, Dynamic Programming | golang |
| 64 | Minimum Path Sum | Medium | Array, Dynamic Programming | golang |
| 71 | Simplify Path | Medium | String, Stack | golang |
| 73 | Set Matrix Zeroes | Medium | Array | golang |
| 74 | Search a 2D Matrix | Medium | Array, Binary Search | golang |
| 75 | Sort Colors | Medium | Array, Two Pointers, Sort | golang |
| 79 | Word Search | Medium | Array, Backtracking | golang |
| 101 | Symmetric Tree | Easy | Tree, Depth-first Search,Breadth-first Search | golang |
| 108 | Convert Sorted Array to Binary Search Tree | Easy | Tree, Depth-first Search | golang |
| 110 | Balanced Binary Tree | Easy | Tree, Depth-first Search | golang |
| 111 | Minimum Depth of Binary Tree | Easy | Tree, Depth-first Search,Breadth-first Search | golang |
| 121 | Best Time to Buy and Sell Stock | Easy | Array | golang |
| 122 | Best Time to Buy and Sell Stock II | Easy | Array, Greedy | golang |
| 125 | Valid Palindrome | Easy | String, Two Pointers | golang |
| 168 | Excel Sheet Column Title | Easy | Math | golang |
| 171 | Excel Sheet Column Number | Easy | Math | golang |
| 172 | Factorial Trailing Zeroes | Easy | Math | golang |
| 190 | Reverse Bits | Easy | Bit Manipulation | golang |
| 198 | House Robber | Easy | Dynamic Programming | golang |
| 199 | Binary Tree Right Side View | Medium | Tree, Depth-first-Search, Breadth-first-Search | golang |
| 226 | Invert Binary Tree | Easy | Tree | golang |
| 257 | Binary Tree Paths | Easy | Tree, Depth-first-Search | golang |
| 258 | Add Digits | Easy | Math | golang |
| 263 | Ugly Number | Easy | Math | golang |
| 264 | Ugly Number II | Medium | Math,Dynamic Programming , Heap | golang, c |
| 292 | Nim Game | Easy | Brainteaser, Minimax | golang |
| 299 | Bulls and Cows | Easy | Hsh Table | golang |
| 343 | Integer Break | Medium | Math, Dynamic Programming | golang, c |
| 389 | Find the Difference | Easy | Hash Table, Bit Manipulation | golang |
| 485 | Max Consecutive Ones | Easy | Array | golang, c |
| 496 | Next Greater Element I | Easy | Stack | golang |
| 530 | Minimum Absolute Difference in BST | Easy | Tree | golang |
| 532 | K-diff Pairs in an Array | Easy | Array, Two Pointers | golang |
| 566 | Reshape the Matrix | Easy | Array | golang |
| 687 | Longest Univalue Path | Easy | Tree, Recursion | golang |
| 783 | Minimum Distance Between BST Nodes | Easy | Tree, Recursion | golang |
| 1137 | N-th Tribonacci Number | Easy | Recursion | golang |
| 1295 | Find Numbers with Even Number of Digits | Easy | Array | golang, c |
| # | Title | Difficulty | Solution |
|---|---|---|---|
| 175 | Combine Two Tables | Easy | MySQL |
| 176 | Second Highest Salary | Easy | MySQL |
| 178 | Rank Scores | Medium | MySQL |
| 180 | Consecutive Numbers | Medium | MySQL |
| 181 | Employees Earning More Than Their Managers | Easy | MySQL |
| 182 | Duplicate Emails | Easy | MySQL |
| 183 | Customers Who Never Order | Easy | MySQL |
| 184 | Department Highest Salary | Medium | MySQL |
| 185 | Department Top Three Salaries | Hard | MySQL |
| 192 | Rising Temperature | Easy | MySQL |
| 196 | Delete Duplicate Emails | Easy | MySQL |
| # | Title | Difficulty | Solution |
|---|---|---|---|
| offer-03-01 | Duplication In Array | Easy | c |
| offer-03-02 | Duplication In Array No Edit | c | |
| offer-04 | Find In Partially Sorted Matrix | Easy | c |
| offer-05 | Replace Spaces | Easy | c |
| offer-06 | Print List In Reversed Order | Easy | c |
| offer-07 | Construct Binary Tree | Medium | c |
| offer-08 | Next Node In Binary Tree | c | |
| offer-09 | Queue With Two Stacks | Easy | c |
| offer-10 | Fibonacci | Easy | c |
| offer-11 | Min Number In Rotated Array | Easy | c |
| offer-12 | String Path In Matrix | Medium | c |
| offer-13 | Robot Move | Medium | c |
| offer-14-01 | Cutting Rope I | Medium | c |
| offer-14-02 | Cutting Rope II | Medium | c |
| offer-15 | Number Of 1 In Binary | Easy | c |
| offer-16 | Power | Medium | c |
| offer-17 | Print 1 To Max Of N Digits | Easy | c |
| offer-18-01 | Delete Note In List | Easy | c |
| offer-20 | Numeric Strings | Medium | c |
| offer-21 | Reorder Array | Easy | c |
| offer-22 | Kth Node From End | Easy | c |
| offer-23 | Entry Node In List Loop | c | |
| offer-24 | Reverse List | Easy | c |
| offer-25 | Merge Sorted Lists | Easy | c |
| offer-26 | Substructure In Tree | Medium | c |
| offer-27 | Mirror Of Binary Tree | Easy | c |
| offer-28 | Symmetrical Binary Tree | Easy | c |
| offer-29 | Print Matrix | Easy | c |
| offer-30 | Mini Stack | Easy | c |
| offer-31 | Stack Push Pop Order | Medium | c |
| offer-32-01 | Print Tree From Top To Bottom | Medium | c |
| offer-32-02 | Print Trees In Lines | Easy | c |
| offer-32-03 | Print Trees In Zigzag | Medium | c |
| offer-33 | Squence Of BST | Medium | c |
| offer-34 | Path In Tree | Medium | c |
| offer-39 | More Than Half Number | Easy | c |
| offer-40 | K Least Numbers | Easy | c |
| offer-42 | Greatest Sum Of Subarrays | Easy | c |
| offer-47 | Max Value Of Gifts | Medium | c |
| offer-49 | Ugly Number | Easy | c |
| offer-50-01 | First Not Repeating Char | Easy | c |
| offer-52 | First Common Nodes In Lists | Easy | c |
| offer-53-01 | Number Of K | Easy | c |
| offer-53-02 | Missing Number | Easy | c |
| offer-53-03 | Integer Identical To Index | Easy | c |
| offer-54 | Kth Node In BST | Easy | c |
| offer-55-01 | Tree Depth | Easy | c |
| offer-55-02 | Balanced Binary Tree | Easy | c |
| offer-56-01 | Numbers Appear Once | Medium | c |
| offer-56-02 | Numbers Appearing Once | Medium | c |
| offer-57-01 | Two Numbers With Sum | Easy | c |
| offer-57-02 | Continuous Squence With Sum | Easy | c |
| offer-58-01 | Reverse Words In Sentence | Easy | c |
| offer-58-02 | Left Rotate String | Easy | c |
| offer-59-02 | Queue With Max | Medium | c |
| offer-61 | Continous Cards | Easy | c |
| offer-62 | Last Number In Circle | Easy | c |
| offer-63 | Maximal Profit | Medium | c |
| offer-64 | Accumulate | Medium | c |
| offer-65 | Add Two Numbers | Easy | c |
| offer-66 | Constuct Array | Easy | c |
| offer-68-01 | Common Parent In Tree | Easy | c |
| offer-68-02 | Common Parent In Tree | Easy | c |
reference: