#include <iostream>
using namespace std;
int a, b, sa, sb, d, i, r;
int main()
{
cin >> a >> b;
sa=0;
while(a!=0)
{
sa=sa+a%10;
a=a/10;
}
sb=0;
while(b!=0)
{
sb=sb+b%10;
b=b/10;
}
d = sa;
i = sb;
r=d%i;
while(r!=0)
{
d=i;
i=r;
r=d%i;
}
cout << i;
return 0;
}