ac

import java.util.*;


public class Main {

    public static Scanner sc = new Scanner(System.in);

    static int gcb(int m, int n){
        if(n > m){
            int tmp = m;
            m = n;
            n = tmp;
        }
        return m % n == 0 ? n : gcb(n, m % n);
    }

    public static void main(String[] args) {
        int m = sc.nextInt();
        int n = sc.nextInt();
        int gcb = gcb(m, n);
        System.out.println(gcb);
    }

}

import java.util.*;


public class Main {

    public static Scanner sc = new Scanner(System.in);

    static int gcb(int m, int n){
        if(n > m){
            int tmp = m;
            m = n;
            n = tmp;
        }
        int r = m % n;
        while (r != 0){
            m = n;
            n = r;
            r = m % n;
        }
        return n;
    }

    public static void main(String[] args) {
        int m = sc.nextInt();
        int n = sc.nextInt();
        int gcb = gcb(m, n);
        System.out.println(gcb);
    }

}