#include<stdio.h>
int main(){
    int a,b;
    if(scanf("%d %d",&a,&b)!=2){
        printf("Invalid input");
    }
    if(a<0)a=-a;
    if(b<0)b=-b;
    while(b !=0)
      int temp
      temp = b;
      b=a%b;
      a=temp;
}
 printf("%d",a);
}