import java.util.Scanner;

public class Gcd {
    static int gcd(int a, int b) {
        while (b != 0) {
            int t = a % b;
            a = b;
            b = t;
        }
        return Math.abs(a);
    }

    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));
        sc.close();
    }
}