use c to Write a function that calculates the greatest common divisor $($GCD$)$ of two positive integers. The

three function parameters are the two positive integers and a pointer indicating the location to which the result

should the written. The function should return $0$ in case of successful execution or return $-1$ in case of

malformed$/$bad input.

int gcd$\_$calculator$($int $a,$ int $b,$ int ${?}^{**}gcd)$; $//$function prototype