The greatest common divisor (GCD) of two integers (of which at least one is nonzero) is the largest positive integer that divides the numbers. Write a C function gcd that accepts two integers and returns 1 if both the integers are zero, otherwise it returns their GCD. Write a C program (that includes the function gcd) which accepts two integers and prints their GCD.

Sample output:

Enter two integers: 0 0

At least one number must be nonzero

Enter two integers: 0 4

GCD of 0 and 4 is 4

Enter two integers: 12 8

GCD of 12 and 8 is 4