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4,310 interview questions, answered.

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94 questions

  1. 73Given a string s, return true if the s can be a palindrome after deleting at most one character from it.MediumCoding· Meta
  2. 74Find the first common ancestor of two nodes in a binary tree.MediumCoding· Meta
  3. 75Given a bookstore database schema, write SQL queries using joins and aggregations to answer questions about sales, inventory, and customer data.MediumCodingData· Meta
  4. 76Build a CalculatorMediumCoding· Adobe, Apple
  5. 77Construct a binary tree given its preorder and inorder traversals.MediumCoding· Adobe, Amazon
  6. 78Find the number of users who called three or more people in the last week.MediumCodingData· Meta
  7. 79Custom Sort StringMediumCoding· Meta
  8. 80Design a data structure that supports insert, delete, search, and retrieve in constant time.MediumCoding· Meta
  9. 81Determine if a given binary tree is a binary search tree (BST).MediumCoding· Adobe, Google
  10. 82Given an array of points and a point P, find the k closest points to P.MediumCoding· Amazon, LinkedIn
  11. 83Given an array, find the two sum.EasyCoding· Adobe, Amazon
  12. 84Given an array representing the height of buildings from a sea beach, return an array of heights of the buildings that have a sea view.MediumCoding· Meta
  13. 85Implement a doubly linked list.MediumCoding· Anduril, Apple
  14. 86What percentage of users who were active on Messenger yesterday made a video call yesterday?MediumCodingData· Meta
  15. 87Given a head node of a linked list, delete k-th node from the end of the list.MediumCoding· Meta
  16. 88Reverse a linked list.EasyCoding· Adobe, Apple
  17. 89Find the smallest missing element from a sorted array.EasyCodingTechnical· Meta
  18. 90Sort a doubly linked list using merge sort.MediumCodingTechnical· Meta
  19. 91Given an array of integers, print all subarrays that sum to zero.MediumCodingData· Meta
  20. 92Find the sum of all elements in a binary tree that fall within the range [low, high], where 'low' and 'high' are integers.MediumCoding· Meta
  21. 93Valid ParenthesesEasyCoding· Apple, Booking.com
  22. 94Is this a valid palindrome?EasyCoding· Adobe, Apple