using System;

public class Program

{

    public static void Main()

    {

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

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

        while(b!=0)

        {

            var oldB = b;

            b = a % b;

            a = oldB;

        }

        Console.WriteLine(a);

​

    }

}