Contains Duplicate: the skills you need first
Updated
LeetCode · easy · hash sets. Insert as you scan. A failed insert, or a contains-hit, is the duplicate.
Skills this problem builds on
Stuck on Contains Duplicate? It is usually one of these. Get each one solid and the solution stops being a trick.
- Detect a duplicate with a seen-set
- Insert one value into a set
- Return early on a set hit
check which ones you have 10 minutes, free, no account.