#include<fstream>
using namespace std;
int cmmdc(int a, int b)
{
    if (a%b==0)
    {
        return b;
    }
    else
    {
        return cmmdc(b,a%b);
    }
}
int main()
{
    long a,b;
    ifstream in("cmmdc.in");
    ofstream out("cmmdc.out");
    in>>a;
    in>>b;
    if (cmmdc(a,b)<=30000)
    {
        out<<cmmdc(a,b);
        if (cmmdc(a,b)==1)
        {
            out<<"0";
        }
    }
    out.close();
    in.close();
    return 0;
}