| 2 | Add Two Numbers | Medium |
| 3 | Longest Substring Without Repeating Characters | Medium |
| 5 | Longest Palindromic Substring | Medium |
| 8 | String to Integer (atoi) | Medium |
| 11 | Container With Most Water | Medium |
| 13 | Roman to Integer | Easy |
| 14 | Longest Common Prefix | Easy |
| 15 | 3Sum | Medium |
| 17 | Letter Combinations of a Phone Number | Medium |
| 19 | Remove Nth Node From End of List | Medium |
| 20 | Valid Parentheses | Easy |
| 22 | Generate Parentheses | Medium |
| 25 | Reverse Nodes in k-Group | Hard |
| 26 | Remove Duplicates from Sorted Array | Easy |
| 26 | Remove Duplicates from Sorted Array | Hard |
| 27 | Remove Element | Hard |
| 33 | Search in Rotated Sorted Array | Medium |
| 34 | Find First and Last Position of Element in Sorted Array | Medium |
| 35 | Search Insert Position | Easy |
| 42 | Trapping Rain Water | Hard |
| 48 | Rotate Image | Medium |
| 49 | Group Anagrams | Medium |
| 50 | Pow(x, n) | Medium |
| 51 | N-Queens | Hard |
| 53 | Maximum Subarray | Medium |
| 54 | Spiral Matrix | Medium |
| 55 | Jump Game | Hard |
| 56 | Merge Intervals | Medium |
| 61 | Rotate List | Medium |
| 69 | Sqrt(x) | Easy |
| 70 | Climbing Stairs | Easy |
| 73 | Set Matrix Zeroes | Medium |
| 74 | Search a 2D Matrix | Medium |
| 75 | Sort Colors | Medium |
| 78 | Subsets | Medium |
| 80 | Remove Duplicates from Sorted Array II | Hard |
| 88 | Merge Sorted Array | Easy |
| 88 | Merge Sorted Array | Hard |
| 118 | Pascal's Triangle | Easy |
| 121 | Best Time to Buy and Sell Stock | Easy |
| 121 | Best Time to Buy and Sell Stock | Hard |
| 122 | Best Time to Buy and Sell Stock II | Hard |
| 138 | Copy List with Random Pointer | Medium |
| 150 | Evaluate Reverse Polish Notation | Medium |
| 151 | Reverse Words in a String | Medium |
| 153 | Find Minimum in Rotated Sorted Array | Medium |
| 155 | Min Stack | Medium |
| 162 | Find Peak Element | Medium |
| 169 | Majority Element | Medium |
| 189 | Rotate Array (Approach 1 ) | Medium |
| 189 | Rotate Array (Approach 2 ) | Medium |
| 189 | Rotate Array | Hard |
| 198 | House Robber | Medium |
| 200 | Number of Islands (Approach 1) | Medium |
| 200 | Number of Islands (Approach 2) | Medium |
| 205 | Isomorphic Strings | Easy |
| 207 | Course Schedule | Medium |
| 215 | Kth Largest Element in an Array | Medium |
| 227 | Basic Calculator II | Medium |
| 236 | Lowest Common Ancestor of a Binary Tree | Medium |
| 237 | Delete Node in a Linked List | Medium |
| 238 | Product of Array Except Self | Medium |
| 242 | Valid Anagram | Easy |
| 253 | Meeting Rooms II (Approach 1) | Medium |
| 253 | Meeting Rooms II (Approach 2) | Medium |
| 274 | H-Index | Hard |
| 283 | Move Zeroes | Easy |
| 345 | Reverse Vowels of a String | Easy |
| 451 | Sort Characters By Frequency | Medium |
| 540 | Single Element in a Sorted Array | Medium |
| 560 | Subarray Sum Equals K | Medium |
| 605 | Can Place Flowers | Easy |
| 636 | Exclusive Time of Functions | Medium |
| 704 | Binary Search | Easy |
| 796 | Rotate String | Easy |
| 875 | Koko Eating Bananas | Medium |
| 1011 | Capacity To Ship Packages Within D Days | Medium |
| 1071 | Greatest Common Divisor of Strings | Easy |
| 1101 | The Earliest Moment When Everyone Become Friends | Medium |
| 1283 | Find the Smallest Divisor Given a Threshold | Medium |
| 1431 | Kids With the Greatest Number of Candies | Easy |
| 1614 | Maximum Nesting Depth of the Parentheses | Easy |
| 1752 | Check if Array Is Sorted and Rotated | Easy |
| 1768 | Merge Strings Alternately | Easy |
| 1903 | Largest Odd Number in String | Easy |
| 2140 | Solving Questions With Brainpower | Medium |
| 2965 | Find Missing and Repeated Values | Easy |
| 3169 | Count Days Without Meetings | Medium |
| 3481 | Apply Substitutions | Medium |
| - | Template | - |
| - | Implement Upper Bound | Misc |
| - | Implement Lower Bound | Misc |
| - | Calculate Floor & Ceiling | Misc |
| - | Number of occurrence | Misc |
| - | Flatten A Linked List | Misc |
| - | Find Nth Root Of M | Misc |
