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 22 matching · 2723 totalSort: id ↑
No.ProblemDifficulty
- 0038Count and SayMed
- 0188Number of IslandsMed
- 0631Map Sum PairsMed
- 0687Flood FillEasy
- 0694Delete and EarnMed
- 0695Cherry PickupHard
- 0697Network Delay TimeMed
- 1103Can Make Palindrome from SubstringMed
- 1117Critical Connections in a NetworkHard
- 1142Dice Roll SimulationHard
- 1153Maximum Profit in Job SchedulingHard
- 1228Number of Operations to Make Network ConnectedMed
- 1233Minimum Number of Taps to Open to Water a GardenHard
- 1243Reduce Array Size to The HalfMed
- 1270Increasing Decreasing StringEasy
- 1318Constrained Subsequence SumHard
- 1502Sort Array by Increasing FrequencyEasy
- 1514Create Sorted Array through InstructionsHard
- 1528Minimum Initial Energy to Finish TasksHard
- 1663Number of Different Subsequences GCDsHard
Showing 20 of 22