# Mixed / Design

- [Two Sum (4 Qs)](/leetcode/mixed-design/two-sum-4-qs.md): Series of problems related to "Two Sum"
- [0001. Two Sum](/leetcode/mixed-design/two-sum-4-qs/0001.-two-sum.md): Easy  |  Hash Table  |  28 ms (93.73%),  13.4 MB (79.11%)
- [0167. Two Sum II - Input array is sorted](/leetcode/mixed-design/two-sum-4-qs/0167.-two-sum-ii-input-array-is-sorted.md): Easy  |  Two Pointer  |  56 ms (95.70%),  14.8 MB (32.12%)
- [0170. Two Sum III - Data structure design](/leetcode/mixed-design/two-sum-4-qs/0170.-two-sum-iii-data-structure-design.md): Easy  |  Binary Search  |  80 ms (100.00%),  20.2 MB (85.90%)
- [0653. Two Sum IV - Input is a BST](/leetcode/mixed-design/two-sum-4-qs/0653.-two-sum-iv-input-is-a-bst.md): Easy  |  Binary Search Tree + Stack  |  72 ms (92.85%),  16.6 MB (76.64%)
- [0015. 3Sum](/leetcode/mixed-design/0015.-3sum.md): Medium  |  Math + Hash Table  |  624 ms (97.81%),  17.8 MB (32.19%)
- [0208. Implement Trie (Prefix Tree)](/leetcode/mixed-design/0208.-implement-trie-prefix-tree.md): Medium  |  Design + String  |  112 ms (99.40%),  29.6 MB (93.89%)