using System;

public class Program

{

    public static void Main()

    {

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

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

        while (b != 0)

        {var oldB = b;

         b = a % b;

         a = oldB;

         //Console.WriteLine(a);

        }

        if (b == 0)

        {

            Console.WriteLine(a);

        }

    }   

}