need some help thanks in advance

I need to write an iterative function of the program I wrote as recursive.

I am a total rookie at this c programing game. I got my program working with a recursive function and it does what it is suppose to do.

Example: 6 and 15 = 3 ; 15 and 22 =1

I gave it a shot writing the program without the recursive function but it doesnt compute properly.

Can someone help me out with this.

Code:

`/* HERE IS MY RECURSIVE PROGRAM IT WORKS PERFECTLY /*`

/* #include <stdio.h> */

/* int gcd (int a, int b); */

/* int main() */

/* { */

/* int a=0; */

/* int b=0; */

/* printf(" This program will compute greatest common divisor of two integers. \n"); */

/* printf("Please enter two integers: \n\n"); */

/* scanf("%d", &a); */

/* scanf("%d", &b); */

/* printf("\n The greatest common denominator of %d and %d is %d \n", a, b, gcd(a,b)); */

/* return 0; */

/* } */

/* Recursive Function */

/* int gcd (int a,int b)*/

/* { */

/* int r; */

/* if ((r=a%b) == 0) */

/* return b; */

/* else */

/* return gcd(b, r); */

/* } */

/* HERE IS MY ATTEMPT TO DO THIS ITERATIVE FUNCTION */

#include <stdio.h>

int gcd (int a, int b);

int main()

{

int a=0;

int b=0;

int r=0;

printf(" This program will compute greatest common divisor of two integers. \n");

printf("Please enter two integers: \n\n");

scanf("%d", &a);

scanf("%d", &b);

r=(a%b);

printf("\n The greatest common denominator of %d and %d is %d \n", a, b, r);

return 0;

}