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
20 of 28 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0001Two SumEasy
- 0014Longest Common PrefixEasy
- 0054Spiral MatrixMed
- 0121Best Time to Buy and Sell StockEasy
- 0122Best Time to Buy and Sell Stock IIMed
- 0203Kth Largest Element in an ArrayMed
- 0331Reverse StringEasy
- 0455Validate IP AddressMed
- 0660Design HashMapEasy
- 0689Asteroid CollisionMed
- 0829Koko Eating BananasMed
- 0835Boats to Save PeopleMed
- 0858Fruit Into BasketsMed
- 0931Squares of a Sorted ArrayEasy
- 0948Rotting OrangesMed
- 1670Minimum Operations to Make the Array IncreasingEasy
- 1680Frequency of the Most Frequent ElementMed
- 1805Minimize the Difference Between Target and Chosen ElementsMed
- 1848Smallest K-Length Subsequence With Occurrences of a LetterHard
- 1857The Time When the Network Becomes IdleMed
Showing 20 of 28