How to find GCD of two numbers in C Language

C Program for GCD of Two Numbers:

#include<stdio.h>
void main()
{
int x, y;
x = 12; y = 18;

while(x != y)
{
if(x > y)
x = x - y;
else
y = y - x;
}

printf("GCD of x and y is = %d", x);
}