#include<fstream>
#include<iostream>
using namespace std;
ifstream in("cmmdc.in");
ofstream out("cmmdc.out");
int cmmdc(int a,int b)
{
    int aux;
    while(b!=0)
    {
        aux=b;
        b=a%b;
        a=aux;
    }
    return a;
}
int main()
{
    int n;
    long int x,y;
    in>>x>>y;
    if(cmmdc(x,y)==1)
        out<<"0";
    else
    out<<cmmdc(x,y);

}