UCLN

/*
 * UCLN.cpp
 *
 * Copyright 2014 by nguyenvanquan7826
 *
 * Email : [email protected]
 * Blog : nguyenvanquan7826.wordpress.com
 *
 */

#include <iostream>

using namespace std;

int UCLN(int a, int b){
    if (a%b == 0) return b;
    return (UCLN(b, a%b));
}

int main (int argc, char **argv)
{
    int a, b;
    cin >> a >> b;
    cout << UCLN(a, b);
    return 0;
}