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
19 of 19 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0001Two SumEasy
- 0004Median of Two Sorted ArraysHard
- 0005Longest Palindromic SubstringMed
- 0012Integer to RomanMed
- 0014Longest Common PrefixEasy
- 0025Reverse Nodes in k-GroupHard
- 0031Next PermutationMed
- 0033Search in Rotated Sorted ArrayMed
- 0121Best Time to Buy and Sell StockEasy
- 0138Copy List with Random PointerMed
- 0146LRU CacheMed
- 0160Intersection of Two Linked ListsEasy
- 0195Course ScheduleMed
- 0198Course Schedule IIMed
- 0829Koko Eating BananasMed
- 0935Time Based Key-Value StoreMed
- 0948Rotting OrangesMed
- 1234Break a PalindromeMed
- 2020Find Palindrome With Fixed LengthMed
All 19 matching problems loaded