problem 1010 ,求gcb

#include <stdio.h>


int gcb(int a, int b);

void swap(int * a, int * b);

int main()
{
	int a, b;
	while(scanf("%d%d",&a , &b) == 2)
	{
		printf("%d\n",gcb(a, b));
	}

	return 0;
}

int gcb(int a, int b)
{
	if(a < b)
		swap(&a, &b);

	while(a % b)
	{
		a = a % b;
		swap(&a, &b);
	}

	return b;
}

void swap(int * a, int * b)
{
	int temp = * a;
	*a = *b;
	*b = temp;
}