#include <stdio.h>
int main()
{
	int n=0 , m=0 ,min,i;
	while (n <= 0||m<=0)
	{
		printf("Vui long nhap n:");
		scanf_s("%d", &n);
		printf("Vui long nhap m:");
		scanf_s("%d", &m);
	}
	min = m;
	if (n<min)
	{
		min = n;
	}
	for (i =min; i>=1; i--)
	{
		
		if (m%i==0 && n%i==0)
		{
			printf("GCD=%d", i);
			break;
		}
	}
	return 1;
}