#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<1||n>100||m<1||m>100)
    printf("Invalid input");
    else
    printf("%d",gcd(n,m));
    return 0;
}