using System;

public class Program

{

    public static void Main()

    {

        DateTime Start = new DateTime(2018, 10, 31);

        DateTime End = new DateTime(2018, 11, 2);

        int days = (int)(End - Start).TotalDays + 1;

        int holidays = days / 7 * 2;

        int remain = days % 7;

        DateTime dt = End.AddDays(-remain);

        while (dt.Date <= End.Date)

        {

            if (dt.DayOfWeek == DayOfWeek.Saturday || dt.DayOfWeek == DayOfWeek.Sunday)

                holidays++;

            dt = dt.AddDays(1);

        }

        int year = Start.Year;

        do

        {

            dt = new DateTime(year, 12, 25); //is chritsmass right?

            if (dt >= Start && dt <= End && dt.DayOfWeek!=DayOfWeek.Saturday && dt.DayOfWeek != DayOfWeek.Sunday) holidays++;

            dt = new DateTime(year, 7, 4); // 4th of july

            if (dt >= Start && dt <= End && dt.DayOfWeek!=DayOfWeek.Saturday && dt.DayOfWeek != DayOfWeek.Sunday) holidays++;

            dt = new DateTime(year, 10, 31); // holoween

            if (dt >= Start && dt <= End && dt.DayOfWeek!=DayOfWeek.Saturday && dt.DayOfWeek != DayOfWeek.Sunday) holidays++;

            year++;

        } while (year <= End.Year);

        int bussinessDays = days - holidays;

        Console.WriteLine($"holidays : {holidays}");

        Console.WriteLine($"bussinessDays : {bussinessDays}");

    }

}