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
14 of 14 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0005Longest Palindromic SubstringMed
- 0020Valid ParenthesesEasy
- 0022Generate ParenthesesMed
- 0049Group AnagramsMed
- 0121Best Time to Buy and Sell StockEasy
- 0188Number of IslandsMed
- 0190Happy NumberEasy
- 0230Valid AnagramEasy
- 0309Coin ChangeMed
- 0386Evaluate DivisionMed
- 0964Pairs of Songs With Total Durations Divisible by 60Med
- 1396Path with Maximum ProbabilityMed
- 2372Maximize Greatness of an ArrayMed
- 2724Find the Maximum Sum of Node ValuesHard
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