using System;
using System.Collections.Generic;
namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
#if LocalDebug
            var exStdIn = new System.IO.StreamReader("stdin.txt");
            System.Console.SetIn(exStdIn);
#endif
            var Date = new DateTime(2015, 1, 1);
            var Cnt = 0;

            for (int i = 0; i < 365; i++)
            {
                var DaySum = (Date.Day / 10) + (Date.Day % 10);

                if (Date.Month == DaySum)
                {
                    Cnt++;
                }

                Date = Date.AddDays(1);
            }
            Console.WriteLine(Cnt);

#if LocalDebug
            System.Console.ReadKey();
#endif
        }




        static int GetData()
        {
            return int.Parse(Console.ReadLine());
        }

        static string[] GetList()
        {
            return Console.ReadLine().Split(' ');
        }



    }
}