#include<stdio.h>
#include<stdlib.h>
int gcd(int a,int b){
    while(b!=0){
        int temp=b;
        b=a%b;
        a=temp;
    }
    return abs(a);
}
int main(){
    int n,m;
    if(scanf("%d %d",&n ,&m)!=2||n<-100||n>100)||m<-100||m>100){
        printf("Invalid input");
    }else{
        printf("%d",gcd(n,m));
    }
    return 0;
    
}