using System;

class CalculateGCD
{
    static void Main()
    {
        int a = int.Parse(Console.ReadLine());
        int b = int.Parse(Console.ReadLine());
        int reminder = 1;

        while (reminder != 0)
        {
            reminder = a % b;
            a = b;
            b = reminder;
        }

        Console.WriteLine(a);


    }
}