using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace tes
{
	class contest
	{
		static void Main(string[] args)
		{
			var num = Console.ReadLine().Split(' ').Select(int.Parse).ToArray();
            Console.WriteLine(gcd(num[0],num[1]));
		}
		static int gcd(int a, int b)
        {
            return (a % b == 0) ? a : gcd(a % b, a);
        }

	}
}