1. Find gcd(a^n, c) where a, n and c can vary from 1 to 10^9
  2. Check if two strings are permutation of each other
  3. Add two unsigned numbers using bits
  4. Number of possible pairs of Hypotenuse and Area to form right angled triangle
  5. Tail recursion to calculate sum of array elements.
  6. Find maximum among x^(y^2) or y^(x^2) where x and y are given
  7. Count numbers which can be represented as sum of same parity primes
  8. Maximum possible intersection by moving centers of line segments
  9. Number of ways a convex polygon of n+2 sides can split into triangles by connecting vertices
  10. Check if Decimal representation of an Octal number is divisible by 7
  11. Number of Permutations such that no Three Terms forms Increasing Subsequence
  12. Find minimum possible digit sum after adding a number d
  13. Find maximum in a stack in O(1) time and O(1) extra space
  14. Check whether it is possible to join two points given on circle such that distance between them is k
  15. Maximize number of nodes which are not part of any edge in a Graph
  16. Minimum number of nodes in an AVL Tree with given height
  17. Optimal sequence for AVL tree insertion (without any rotations)
  18. MakeFile in C++ and its applications
  19. Find if array has an element whose value is half of array sum
  20. In-Place Merge Sort
  21. Find a value whose XOR with given number is maximum
  22. Generate all rotations of a number
  23. Check if array can be divided into two sub-arrays such that their absolute difference is K
  24. Minimum operations required to modify the array such that parity of adjacent elements is different
  25. Find Intersection of all Intervals
  26. Find sub-matrix with the given sum
  27. Minimum index i such that all the elements from index i to given index are equal
  28. Number of trailing zeroes in base 16 representation of N!
  29. Minimum operations to make frequency of all characters equal K
  30. Numbers in a Range with given Digital Root
  31. Check if Matrix remains unchanged after row reversals
  32. Check if the given array can be reduced to zeros with the given operation performed given number of times
  33. Minimum length of square to contain at least half of the given Coordinates
  34. Maximal Disjoint Intervals
  35. Maximum points covered after removing an Interval
  36. Check if factorial of N is divisible by the sum of squares of first N natural numbers
  37. Find triplet such that number of nodes connecting these triplets is maximum
  38. Find if nCr is divisible by the given prime
  39. Find N distinct numbers whose bitwise Or is equal to K
  40. Minimum increments to convert to an array of consecutive integers
  41. Count pairs of elements such that number of set bits in their AND is B[i]
  42. Maximum subset sum such that no two elements in set have same digit in them
  43. Find the element in the matrix generated by given rules
  44. Count of sub-sequences which satisfy the given condition
  45. Find if a binary matrix exists with given row and column sums
  46. Find the Kth smallest element in the sorted generated array
  47. Find optimal weights which can be used to weigh all the weights in the range [1, X]
  48. Split the given array into K sub-arrays such that maximum sum of all sub arrays is minimum
  49. Find minimum length sub-array which has given sub-sequence in it
  50. Number of Quadruples with GCD equal to K
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