Exercise8GreatestCommonDivisor

using System;

class Exercise8GreatestCommonDivisor
{
    static int GCD(int a, int b)
    {
        if (b == 0)
        {
            return a;
        }
        else
        {
            return GCD(b, a % b);
        }
    }
    static void Main()
    {
        int a = int.Parse(Console.ReadLine());
        int b = int.Parse(Console.ReadLine());
        Console.WriteLine(GCD(a, b));
    }
}