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4,310 interview questions, answered.

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88 questions

  1. 49Build a Basic Regex ParserHardCoding· Adobe, Apple
  2. 50Given a list of conversion items between symbols, write an algorithm to return the conversion ratio for each pair of symbols.HardCodingTechnical· Snap
  3. 51Design a banking system to facilitate account creation, deposits, transfers, and listing the most active accounts by total monetary activity, with commands entered via parsing CSV/JSON.HardCoding· Capital One
  4. 52Implement a hashmap without using any libraries.HardCoding· Apple, Goldman Sachs
  5. 53Design a marketplace where freelancers bid on contract jobs with the lowest bid winning the contract.HardCoding· Intuit
  6. 54Find the first missing positive number in an array.HardCoding· Amazon
  7. 55Design and implement an in-memory key-value store that supports set, transactional begin, commit, and abort operations.HardCoding· OpenAI, xAI
  8. 56Implement LRU Cache.HardCoding· Accenture, Adobe
  9. 57Merge k sorted linked lists.HardCoding· Adobe, Apple
  10. 58Given two strings (Word 1 and Word 2) and a list of valid words from a dictionary, return the minimum number of operations required to convert Word 1 to Word 2.HardCoding· Airbnb
  11. 59Given a string of parentheses types and an array of their efficiency ratings, write a function to find the most efficient valid parentheses sequence that can be formed. Return its total efficiency score.HardCoding· Amazon
  12. 60Given a matrix with a rat, bread, cat, and obstacles, find a path from the rat to the bread that maximizes the minimum distance from cat.HardCoding· Google
  13. 61Session Data Analysis.HardCodingTechnical· Amazon
  14. 62Write a query to find all dates where the stadium had three or more consecutive days with attendance of 100 or more people.HardCodingData· Amazon
  15. 63Given an integer array nums and an integer k, return true if nums has a subarray of at least two elements whose sum is a multiple of k.HardCoding· Adobe, Apple
  16. 64Sudoku SolverHardCoding· Adobe, Apple
  17. 65Calculate the trapped rainwater between bars in a given array.HardCoding· Adobe, Amazon
  18. 66Calculate the number of times a pattern appears in a string.HardCoding· LinkedIn
  19. 67Given an array of points on a plane (x,y), write a function to return the distance between the closest pair of points.HardCoding· Visa
  20. 68Edit distanceHardCoding· Adobe, Amazon
  21. 69Find Monthly Revenue GrowthHardCodingData· Uber
  22. 70Implement a red-black tree.HardCoding· Apple
  23. 71Top Salaries by DepartmentHardCodingData· Tesla
  24. 72Employee HierarchyHardCodingData