| Kth Largest Element in an Array ↗ | Medium | Array, Divide and Conquer, Sorting | |
| Find Peak Element ↗ | Medium | Array, Binary Search | |
| Binary Tree Right Side View ↗ | Medium | Tree, Depth-First Search, Breadth-First Search | |
| Merge Sorted Array ↗ | Easy | Array, Two Pointers, Sorting | |
| Two Sum ↗ | Easy | Array, Hash Table | |
| Pow(x, n) ↗ | Medium | Math, Recursion | |
| Valid Palindrome ↗ | Easy | Two Pointers, String | |
| Simplify Path ↗ | Medium | String, Stack | |
| Merge Intervals ↗ | Medium | Array, Sorting | |
| Sum Root to Leaf Numbers ↗ | Medium | Tree, Depth-First Search, Binary Tree | |
| Copy List with Random Pointer ↗ | Medium | Hash Table, Linked List | |
| LRU Cache ↗ | Medium | Hash Table, Linked List, Design | |
| Best Time to Buy and Sell Stock ↗ | Easy | Array, Dynamic Programming | |
| Merge k Sorted Lists ↗ | Hard | Linked List, Divide and Conquer, Heap (Priority Queue) | |
| Next Permutation ↗ | Medium | Array, Two Pointers | |
| Find First and Last Position of Element in Sorted Array ↗ | Medium | Array, Binary Search | |
| Minimum Window Substring ↗ | Hard | Hash Table, String, Sliding Window | |
| Clone Graph ↗ | Medium | Hash Table, Depth-First Search, Breadth-First Search | |
| Valid Number ↗ | Hard | String | |
| Valid Parentheses ↗ | Easy | String, Stack | |
| Remove Nth Node From End of List ↗ | Medium | Linked List, Two Pointers | |
| Longest Common Prefix ↗ | Easy | Array, String, Trie | |
| Course Schedule ↗ | Medium | Depth-First Search, Breadth-First Search, Graph Theory | |
| Add Two Numbers ↗ | Medium | Linked List, Math, Recursion | |
| Longest Substring Without Repeating Characters ↗ | Medium | Hash Table, String, Sliding Window | |
| Binary Search Tree Iterator ↗ | Medium | Stack, Tree, Design | |
| Remove Duplicates from Sorted Array ↗ | Easy | Array, Two Pointers | |
| Median of Two Sorted Arrays ↗ | Hard | Array, Binary Search, Divide and Conquer | |
| 3Sum ↗ | Medium | Array, Two Pointers, Sorting | |
| Palindrome Number ↗ | Easy | Math | |
| Longest Palindromic Substring ↗ | Medium | Two Pointers, String, Dynamic Programming | |
| Number of Islands ↗ | Medium | Array, Depth-First Search, Breadth-First Search | |
| String to Integer (atoi) ↗ | Medium | String | |
| Word Ladder ↗ | Hard | Hash Table, String, Breadth-First Search | |
| Missing Ranges ↗ | Easy | Array | |
| Sort Colors ↗ | Medium | Array, Two Pointers, Sorting | |
| Subsets ↗ | Medium | Array, Backtracking, Bit Manipulation | |
| Trapping Rain Water ↗ | Hard | Array, Two Pointers, Dynamic Programming | |
| Maximum Subarray ↗ | Medium | Array, Divide and Conquer, Dynamic Programming | |
| Climbing Stairs ↗ | Easy | Math, Dynamic Programming, Memoization | |