using System;
using System.Linq;

public class Program
{
    public static void Main()
    {
        var input = Console.ReadLine().Split(' ').Select(s => int.Parse(s)).ToList();
        var ct = Enumerable.Range(23, 3).Count(x=> x < input[0] || input[1] < x);
        Console.WriteLine("{0}", ct);
        return;
    }
}