This assignment has to be written in C.

Greatest Common Divisor

Your task is to complete the implementation of the gcd function outlined to the left, using recursion. You must use recursion to get full credit.

The gcd function computes the greatest common divisor, also known as the greatest common factor.

The greatest common divisor represents the largest common divisor between two numbers. For instance, the greatest common divisor between 28 and 63 is 7, because 7*4=28, and 7*9=63, and 28 and 63 share no common larger divisor.