DSA
Master the patterns
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Active·2,723
Easy·667
Medium·1,394
Hard·662
Patterns
Recognize the move
Filter the bank by pattern — each card links into the problem index.
Problem index
Browse problems
Search by title, then refine with facets. Sorted by problem ID.
Difficulty
Facets
10 of 10 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0049Group AnagramsMed
- 0230Valid AnagramEasy
- 0309Coin ChangeMed
- 0367Insert Delete GetRandom O(1)Med
- 0368Insert Delete GetRandom O(1) - Duplicates allowedHard
- 0430String CompressionMed
- 0690Parse Lisp ExpressionHard
- 0887Number of Recent CallsEasy
- 2732Shortest Uncommon Substring in an ArrayMed
- 2810String Compression IIIMed
All 10 matching problems loaded