#include <cstdio>
using namespace std;

int A,B;

int euclid(int a,int b)
{
    if(b==0)return a;
    return euclid(b,a%b);
}

int main() {


    freopen("euclid2.in","r",stdin);
    freopen("euclid2.out","w",stdout);

    scanf("%d %d",&A,&B);

    printf("%d",euclid(A,B));

    return 0;
}