Given a positive integer A, return its corresponding column title as appear in an Excel sheet.

Given a column title A as appears in an Excel sheet, return its corresponding column number.

Rearrange a given array so that Arr[i] becomes Arr[Arr[i]] with O(1) extra space.

Given a set of digits (A) in sorted order, find how many numbers of length B are possible whose value is less than number C.

Given a positive integer which fits in a 32 bit signed integer, find if it can be expressed as A^P where P > 1 and A > 0. A and P both shoul

Hamming distance between two non-negative integers is defined as the number of positions at which the corresponding bits are different.

Given an even number ( greater than 2 ), return two prime numbers whose sum will be equal to given number.