#include <stdio.h>

int main() {
    int a,b,t;
    scanf("%d %d",&a,&b);
    if(a==b){
        printf("%d\n",a);
    }
    if(a<b){
        t=a;
        a=b;
        b=t;
    }
    while(1){
        t=b;
        a=a%b;
        //printf("(%d)\n",b);
        if(a==0){
            printf("%d\n",t);
            return 0;
        }
        else{
            t=a;
            a=b;
            b=t;
        }
       // printf("*%d %d*\n",a,b);
    }
}