hash map
Easy
| Number | Note |
|---|---|
| 1. Two Sum | optimize if else (in or not in?), subtraction |
| 383. Ransom Note | |
| 1748. Sum of Unique Elements |
Medium
| Number | Note |
|---|---|
| 49. Group Anagrams |
| Number | Note |
|---|---|
| 1. Two Sum | optimize if else (in or not in?), subtraction |
| 383. Ransom Note | |
| 1748. Sum of Unique Elements |
| Number | Note |
|---|---|
| 49. Group Anagrams |