| 178 | Rank Scores | Medium |
| 179 | Largest Number | Medium |
| 180 | Consecutive Numbers | Medium |
| 184 | Department Highest Salary | Medium |
| 187 | Repeated DNA Sequences | Medium |
| 189 | Rotate Array | Medium |
| 192 | Word Frequency | Medium |
| 194 | Transpose File | Medium |
| 199 | Binary Tree Right Side View | Medium |
| 200 | Number of Islands | Medium |
| 201 | Bitwise AND of Numbers Range | Medium |
| 204 | Count Primes | Medium |
| 207 | Course Schedule | Medium |
| 208 | Implement Trie (Prefix Tree) | Medium |
| 209 | Minimum Size Subarray Sum | Medium |
| 210 | Course Schedule II | Medium |
| 211 | Design Add and Search Words Data Structure | Medium |
| 213 | House Robber II | Medium |
| 215 | Kth Largest Element in an Array | Medium |
| 216 | Combination Sum III | Medium |
| 220 | Contains Duplicate III | Medium |
| 221 | Maximal Square | Medium |
| 222 | Count Complete Tree Nodes | Medium |
| 223 | Rectangle Area | Medium |
| 227 | Basic Calculator II | Medium |
| 229 | Majority Element II | Medium |
| 230 | Kth Smallest Element in a BST | Medium |
| 236 | Lowest Common Ancestor of a Binary Tree | Medium |
| 238 | Product of Array Except Self | Medium |
| 240 | Search a 2D Matrix II | Medium |