| 198 | House Robber | Easy |
| 199 | Binary Tree Right Side View | Medium |
| 200 | Number of Islands | Medium |
| 201 | Bitwise AND of Numbers Range | Medium |
| 202 | Happy Number | Easy |
| 205 | Isomorphic Strings | Easy |
| 206 | Reverse Linked List | Easy |
| 207 | Course Schedule | Medium |
| 208 | Implement Trie (Prefix Tree) | Medium |
| 209 | Minimum Size Subarray Sum | Medium |
| 210 | Course Schedule II | Medium |
| 213 | House Robber II | Medium |
| 215 | Kth Largest Element in an Array | Medium |
| 219 | Contains Duplicate II | Easy |
| 221 | Maximal Square | Medium |
| 224 | Basic Calculator | Hard |
| 226 | Invert Binary Tree | Easy |
| 228 | Summary Ranges | Easy |
| 229 | Majority Element II | Medium |
| 230 | Kth Smallest Element in a BST | Medium |
| 231 | Power of Two | Easy |
| 232 | Implement Queue using Stacks | Easy |
| 234 | Palindrome Linked List | Easy |
| 237 | Delete Node in a Linked List | Medium |
| 238 | Product of Array Except Self | Medium |
| 239 | Sliding Window Maximum | Hard |
| 240 | Search a 2D Matrix II | Medium |
| 242 | Valid Anagram | Easy |
| 258 | Add Digits | Easy |
| 260 | Single Number III | Medium |