1. Count set bits in an integer
  2. Find a triplet such that sum of two equals to third element
  3. Set Matrix Zeroes
  4. Group Anagrams
  5. Find a peak element
  6. Search for a Range
  7. Search a 2D Matrix II
  8. Jump Game
  9. Coin Change
  10. Design a data structure that supports insert, delete, search and getRandom in constant time
  11. Happy Number
  12. Write a program to calculate pow(x,n)
  13. Find Recurring Sequence in a Fraction
  14. Add two numbers without using arithmetic operators
  15. Majority Element
  16. Task Scheduler
  17. A Product Array Puzzle
  18. Game of Life
  19. Find the smallest positive number missing from an unsorted array
  20. Basic Calculator II
  21. Merge Sort for Linked Lists
  22. Word Ladder
  23. Given a matrix of ‘O’ and ‘X’, replace ‘O’ with ‘X’ if surrounded by ‘X’
  24. Friend Circles
  25. Find the longest path in a matrix with given constraints