#include<stdio.h>

int gcd(int a, int b) {
    if (b == 0)
        return a > 0 ? a : -a;
    else
        return gcd(b, a % b);
}

int main() {
    int n, m;
    if (scanf("%d %d", &n, &m) != 2) {
        printf("Invalid input);
        return 0;
    }
    if (n < -100 || n > 100 || m < -100 || m > 100) {
        printf("Invalid input);
        return 0;
    }
    printf("%d\n", gcd(n, m));
    return 0;

    
}