hy

#include <iostream>
using namespace std;
int z(int a, int b){
while(a != b){
if(a > b){
a = a - b;
}
else{
b = b - a;
}
}
return a;
}
int main()
{
int a, b;
cin >> a >> b;
cout << z(a, b);
return 0;
}