#include<iostream>
using namespace std;
int main()
{
	int a,b,GCD,r=1;
	cin>>a>>b;  
    a=a>b?a:b;
    b=b<a?b:a;
  	while(r!=0)
  	{ 
    	r=a%b;
    	a=b;
    	b=r;
  	}
  	GCD=a;
	cout<<"GCD="<<GCD;
	return 0; 
}