#include "stdafx.h"
#include <iostream>
using namespace std;
int nod (int a, int b)
{
int r = 1;
while (r != 0) {
r = a % b;
a = b;
b = r;
}
return a;
}
int _tmain(int argc, _TCHAR* argv[])
{
int a, b;
cin >> a;
cin >> b;
cout << nod(a, b) << endl;
system("pause");
return 0;
}