DSA
Master the patterns
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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
17 of 17 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0012Integer to RomanMed
- 0013Roman to IntegerEasy
- 0036Valid SudokuMed
- 0041First Missing PositiveHard
- 0122Best Time to Buy and Sell Stock IIMed
- 0296Best Time to Buy and Sell Stock with CooldownMed
- 0302Count of Smaller Numbers After SelfHard
- 0309Coin ChangeMed
- 0381Decode StringMed
- 1000Remove All Adjacent Duplicates In StringEasy
- 1138Path with Maximum GoldMed
- 1284Cinema Seat AllocationMed
- 1300Number of Steps to Reduce a Number in Binary Representation to OneMed
- 1301Longest Happy StringMed
- 1898Minimum Number of Food Buckets to Feed the HamstersMed
- 2170Largest Palindromic NumberMed
- 2549Minimum Moves to Spread Stones Over GridMed
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