题解 | #最大公约数#直接调用库函数

//C++版代码
#include <iostream>
#include <numeric>
using namespace std;
int main() {
    int a, b;
    cin >> a >> b;
    cout << gcd(a, b) << endl;
    return 0;
}
//Java版代码
import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        System.out.println(gcd(a, b));
    }
    private static int gcd(int a, int b) {
//        return b == 0 ? a : gcd(b, a % b);//递归写法
        //迭代写法
        while (b != 0) {
            int temp = a % b;
            a = b;
            b = temp;
        }
        return a;
    }
}
#Python版代码
from math import gcd
a, b = map(int, input().split())
print(gcd(a, b))