#include <iostream>
#include <queue>
#include <algorithm>
#include <vector>
#include <unordered_set>
#include <string>
#include <fstream>

using namespace std;

int gcd(int a,int b) {
	return !b ? a : gcd(b,a % b);
}

int main()
{
	fstream cin("euclid2.in");
	ofstream cout("euclid2.out");
	int a, b;
	cin >> a >> b;
	cout << gcd(a,b) << "\n";
	return 0;																
}