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20 questions

  1. 1Merge IntervalsMediumCoding· Blinkit, Docquity Holdings(PBS)
  2. 2Merge two sorted listsEasyCoding· Intuit, Oracle
  3. 3Print all combinations of numbers from 1 to n that sum to n.MediumCoding· Adobe, Apple
  4. 4Find the k-th smallest and k-th largest element in a binary search tree (BST).MediumCodingTechnical· LinkedIn
  5. 5PermutationsMediumCoding· Adobe, Apple
  6. 6Find the longest palindromic subsequence using dynamic programming.MediumCoding· Adobe, Apple
  7. 7Find the lowest common ancestor (LCA) of two nodes in a binary tree.MediumCoding· Apple, LinkedIn
  8. 8Implement LRU Cache.HardCoding· Accenture, Adobe
  9. 9Find the maximum subarray sum.MediumCoding· Adobe, Apple
  10. 10Merge k sorted linked lists.HardCoding· Adobe, Apple
  11. 11Partition an array into two sub-arrays with equal sum.MediumCoding· Apple, LinkedIn
  12. 12Sort an array containing only 0s, 1s, and 2s.MediumCodingTechnical· LinkedIn
  13. 13Calculate the height of a binary tree.EasyCoding· Apple, Google
  14. 14Calculate the number of times a pattern appears in a string.HardCoding· LinkedIn
  15. 15Construct a binary tree from an ancestor matrix.MediumCodingTechnical· LinkedIn
  16. 16Edit distanceHardCoding· Adobe, Amazon
  17. 17Given an array of points and a point P, find the k closest points to P.MediumCoding· Amazon, LinkedIn
  18. 18Given an array of integers, find a tuple of three integers that can form a triangle.MediumCoding· LinkedIn
  19. 19Given an nxn grid of 1s and 0s, return the number of islands in the input.MediumCoding· Adobe, Amazon
  20. 20Valid ParenthesesEasyCoding· Apple, Booking.com