#include <bits/stdc++.h>

using namespace std;

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

int main() {
	int a, b;
	cout << "Nhap a, b: ";
	cin >> a >> b;
	cout << "Ket qua: " << ucln(a, b);
	return 0;
}