| No. | Title | Mark |
|---|---|---|
| 146 | LRU Cache | |
| 155 | Min Stack | |
| 173 | Binary Search Tree Iterator | |
| 208 | Implement Trie (Prefix Tree) | |
| 211 | Design Add and Search Words Data Structure | |
| 225 | Implement Stack using Queues | |
| 232 | Implement Queue using Stacks | |
| 295 | Find Median from Data Stream | |
| 297 | Serialize and Deserialize Binary Tree | |
| 303 | Range Sum Query - Immutable | |
| 304 | Range Sum Query 2D - Immutable | |
| 449 | Serialize and Deserialize BST | |
| 460 | LFU Cache | |
| 716 | Max Stack | |
| 703 | Kth Largest Element in a Stream | |
| 705 | Design HashSet | |
| 706 | Design HashMap | |
| 707 | Design Linked List | |
| 641 | Design Circular Deque | |
| 622 | Design Circular Queue | |
| 1206 | Design Skiplist | |
| 1670 | Design Front Middle Back Queue | |
| 1804 | Implement Trie II (Prefix Tree) | |
| 931 | Maximum Frequency Stack |