| ID | Difficulty | Problem | Topics | Link |
|---|---|---|---|---|
| 0001 | Easy | Two Sum | Array, HashMap | solution |
| 0002 | Medium | Add Two numbers | LinkedList, Recursion | |
| 0011 | Medium | Container With Most Water | Array, Two Pointers, Greedy | solution |
| 0015 | Medium | Three sum | Array, Two Pointers, Sorting | solution |
| 0022 | Medium | Generate Parentheses | String, Dynamic Programming, Backtracking | solution |
| 0036 | Medium | Valid Sudoku | Array, HashTable, Matrix | solution |
| 0042 | Hard | Trapping Rain Water | Array, Two Pointers, Dynamic Programming, Stack | solution |
| 0049 | Medium | Group Anagrams | Array, HashTable, String, Sorting | solution |
| 0121 | Easy | Best Time to Buy and Sell Stock | Array | solution |
| 0125 | Easy | Valid Palindrome | String, Two Pointers | solution |
| 0128 | Medium | Longest Consecutive Sequence | Array, HashSet | solution |
| 0150 | Medium | Evaluate Reverse Polish Notation | Array, Math, Stack | solution |
| 0167 | Medium | Two Sum II - Input Array Is Sorted | Array, Two Pointers | solution |
| 0169 | Easy | Majority Element | Array, HashTable, Counting | solution |
| 0217 | Easy | Contains Duplicate | Array | solution |
| 0219 | Easy | Contains Duplicate II | Array | solution |
| 0238 | Medium | Product of Array Except Self | Array | solution |
| 0242 | Easy | Valid Anagram | String, HashTable | solution |
| 0347 | Medium | Top K Frequent Elements | Array, HashMap, Bucket Sort | Solution |