#include <cstdio>

inline int gcd(int a, int b)
{
    if(!b) return a;
    return gcd(b, a%b);
}

int main()
{
    freopen("euclid2.in","r",stdin);
    freopen("euclid2.out","w",stdout);
    int a, b;
    scanf("%d %d", &a, &b);
    printf("%d\n", gcd(a,b));
    return 0;
}