DSA Tracker

Measured, not curated

The Consensus 75

Apna College, Love Babbar 450 and Striver A2Z were put together by different people, at different times, with no coordination. These 75 problems appear in all three. Nobody picked them — they are what survives when you keep only the problems every sheet already agreed on.

Track these in the app — freeReorder for your target role
75agreed by all 3
27Easy
45Medium
3Hard
19topics covered
370in the full set

Where the agreement concentrates

The three sheets converge hardest on the fundamentals. That distribution is itself the signal — it is what three independent curators thought you cannot skip.

All 75 problems

Easiest first, so there is an obvious place to begin. Every one of these is in Apna College, Love Babbar 450 and Striver A2Z.

  1. 1Best Time to Buy and Sell StockArrays · Easy
  2. 2Majority ElementArrays · Easy
  3. 3Merge Sorted ArraysArrays · Easy
  4. 4Sort an Array of 0s 1s and 2sArrays · Easy
  5. 5Two SumArrays · Easy
  6. 6Binary SearchBinary Search · Easy
  7. 7Sqrt(x)Binary Search · Easy
  8. 8Balanced Binary TreeBinary Trees · Easy
  9. 9Binary Tree Inorder TraversalBinary Trees · Easy
  10. 10Binary Tree Postorder TraversalBinary Trees · Easy
  11. 11Binary Tree Preorder TraversalBinary Trees · Easy
  12. 12Diameter of Binary TreeBinary Trees · Easy
  13. 13Invert Binary TreeBinary Trees · Easy
  14. 14Maximum Depth of Binary TreeBinary Trees · Easy
  15. 15Same TreeBinary Trees · Easy
  16. 16Symmetric TreeBinary Trees · Easy
  17. 17Missing NumberBit Manipulation · Easy
  18. 18Single NumberBit Manipulation · Easy
  19. 19Climbing StairsDynamic Programming · Easy
  20. 20Flood FillGraph · Easy
  21. 21Linked List CycleLinked List · Easy
  22. 22Merge Two Sorted ListsLinked List · Easy
  23. 23Middle of Linked ListLinked List · Easy
  24. 24Palindrome Linked ListLinked List · Easy
  25. 25Reverse Linked ListLinked List · Easy
  26. 26Implement Queue using StacksQueue · Easy
  27. 27Valid ParenthesesStack · Easy
  28. 283SumArrays · Medium
  29. 29Container With Most WaterArrays · Medium
  30. 30Count Subarrays with Given SumArrays · Medium
  31. 31Find the Longest Consecutive SequenceArrays · Medium
  32. 32Maximum SubarrayArrays · Medium
  33. 33Product of Array Except SelfArrays · Medium
  34. 34Sort ColorsArrays · Medium
  35. 35Lowest Common Ancestor of a BSTBST · Medium
  36. 36Validate Binary Search TreeBST · Medium
  37. 37Combination SumBacktracking · Medium
  38. 38Letter Combinations of a Phone NumberBacktracking · Medium
  39. 39PermutationsBacktracking · Medium
  40. 40Rat in a MazeBacktracking · Medium
  41. 41SubsetsBacktracking · Medium
  42. 42Binary Tree Level Order TraversalBinary Trees · Medium
  43. 43Construct Binary Tree from Preorder and InorderBinary Trees · Medium
  44. 44Lowest Common Ancestor of Binary TreeBinary Trees · Medium
  45. 450-1 Knapsack ProblemDynamic Programming · Medium
  46. 46Coin ChangeDynamic Programming · Medium
  47. 47House RobberDynamic Programming · Medium
  48. 48Jump GameDynamic Programming · Medium
  49. 49Longest Common SubsequenceDynamic Programming · Medium
  50. 50Longest Increasing SubsequenceDynamic Programming · Medium
  51. 51Unique PathsDynamic Programming · Medium
  52. 52Number of IslandsGraph · Medium
  53. 53Rotting OrangesGraph · Medium
  54. 54Activity Selection ProblemGreedy · Medium
  55. 55Fractional KnapsackGreedy · Medium
  56. 56Job Sequencing ProblemGreedy · Medium
  57. 57Top K Frequent ElementsHeap · Medium
  58. 58Merge IntervalsIntervals · Medium
  59. 59Add Two NumbersLinked List · Medium
  60. 60Remove Nth Node From End of ListLinked List · Medium
  61. 61Sieve of EratosthenesMath · Medium
  62. 62Merge SortSorting · Medium
  63. 63Quick SortSorting · Medium
  64. 64Generate ParenthesesStack · Medium
  65. 65Min StackStack · Medium
  66. 66Stock Span ProblemStack · Medium
  67. 67Group AnagramsStrings · Medium
  68. 68Longest Palindromic SubstringStrings · Medium
  69. 69Longest Substring Without Repeating CharactersStrings · Medium
  70. 70Reverse Words in a StringStrings · Medium
  71. 71Implement Trie (Prefix Tree)Trie · Medium
  72. 72Two Sum II - Sorted ArrayTwo Pointers · Medium
  73. 73Trapping Rain WaterArrays · Hard
  74. 74N-QueensBacktracking · Hard
  75. 75Largest Rectangle in HistogramStack · Hard

Questions, answered.

What is the Consensus 75?

The 75 problems that appear in all three of the DSA sheets this tracker covers — Apna College, Love Babbar 450 and Striver A2Z. The three lists were built independently, so a problem landing in all of them means three separate curators reached the same conclusion about it.

How is this different from Blind 75?

Blind 75 is one engineer's curated list, and a good one. This is not a curated list at all — it is the intersection of three existing sheets, computed from the dataset. Nobody chose these 75; they are what is left when you keep only the problems everyone already agreed on.

Is 75 enough to prepare for interviews?

It is enough to cover the patterns that repeat. These 75 skew toward the fundamentals — 27 Easy, 45 Medium, 3 Hard, which is what a first pass should look like. Once they are comfortable, the remaining problems in the full 370 are where you specialise for your target role.

Do I have to solve them in this order?

No. They are listed easiest-first so there is an obvious place to start, but the tracker can reorder the whole set for the role you are actually interviewing for, which changes what deserves your attention first.

Then specialise

These 75 are the shared base. What comes after depends on the job — a frontend interview and an SDET interview diverge sharply once the fundamentals are done.

Prep by roleAll 370 problemsBrowse by sheet