DSA
Master the patterns
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Active·2,723
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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
- 0005Longest Palindromic SubstringMed
- 0012Integer to RomanMed
- 0188Number of IslandsMed
- 0411Longest Repeating Character ReplacementMed
- 0781Making A Large IslandHard
- 0835Boats to Save PeopleMed
- 0944Satisfiability of Equality EquationsMed
- 0990Escape a Large MazeHard
- 1091As Far from Land as PossibleMed
- 2526Sorting Three GroupsMed
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