using System;
using System.Linq;
namespace abc
{
    class ex
    {
        static void Main(string[] args)
        {
            var ns = Console.ReadLine().Split().Select(x => int.Parse(x)).ToArray();
            int[] d = { 23, 24, 25 };
            Console.WriteLine(d.Count(x => x < ns[0] || x > ns[1]));
        }
    }
}