#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("cmmdc.in");
ofstream fout("cmmdc.out");
int main()
{
    int a,b;
    fin>>a;
    fin>>b;
    if(a==0)
    fout<<b;
    if(b==0)
    fout<<a;
    if(a==1 || b==1)
    fout<<1;
     while(a!=b)
	{
		if(a>b)
		{
        a=a-b;
		}
		else
		{
        b=b-a;
		}
	}
	fout<<a;
	return 0;
}