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

class Program
{
    public void Proc()
    {
        Reader.IsDebug = false;
        long num = long.Parse(Reader.ReadLine());
        long fbz = num / 15;
        long fz = num / 3 - fbz;
        long bz = num / 5 - fbz;
        
        Console.WriteLine((fz+bz) * 2 + (fbz * 4));

    }
    


    public class Reader
    {
        public static bool IsDebug = true;
        private static String PlainInput = @"



15



 
";
        private static System.IO.StringReader Sr = null;
        public static string ReadLine()
        {
            if (IsDebug)
            {
                if (Sr == null)
                {
                    Sr = new System.IO.StringReader(PlainInput.Trim());
                }
                return Sr.ReadLine();
            }
            else
            {
                return Console.ReadLine();
            }
        }
    }
    static void Main()
    {
        Program prg = new Program();
        prg.Proc();
    }
}