using System;

public class Program

{

    public static void Main()

    {

        int a=int.Parse(Console.ReadLine());

        int b=int.Parse(Console.ReadLine());

        while(b!=0)

        {   

        int obshto=b;

        b=a%b;

        a=obshto;

        }

        Console.WriteLine(a);

    }

}