DSA
Master the patterns
Search the bank, then filter by difficulty, pattern, data structure, or algorithm. Each problem includes approaches, solutions, and walkthroughs.
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
15 of 15 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0023Merge k Sorted ListsHard
- 0056Merge IntervalsMed
- 0162Find Peak ElementMed
- 0166Fraction to Recurring DecimalMed
- 0195Course ScheduleMed
- 0215Basic Calculator IIMed
- 0222Palindrome Linked ListEasy
- 0282Find Median from Data StreamHard
- 0367Insert Delete GetRandom O(1)Med
- 0564Fraction Addition and SubtractionMed
- 0567Range Addition IIEasy
- 0645Stickers to Spell WordHard
- 06711-bit and 2-bit CharactersEasy
- 1251Minimum Number of Steps to Make Two Strings AnagramMed
- 1353Maximum Area of a Piece of Cake After Horizontal and Vertical CutsMed
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