using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Please Enter the day");

        string date_type = Console.ReadLine();

        CalculateReportParameterDate(date_type);

    }

    public static DateTime CalculateReportParameterDate(string date_type)

    {

        DateTime? baseDate = null;

        if(date_type == "today")

            baseDate = DateTime.Today;

​

        else if(date_type == "tomorrow")

            baseDate = DateTime.Today.AddDays(1);

        else if(date_type == "yesterday")

            baseDate = DateTime.Today.AddDays(-1);

        else if(date_type == "LBD")

            baseDate = DateTime.Today.AddDays(-1);

        else if(date_type == "NBD")

            baseDate = DateTime.Today.AddDays(1);

        else if(date_type == "CMS")

            baseDate = DateTime.Today.AddDays(1 - DateTime.Today.Day);

        else if(date_type == "CME")

            baseDate = DateTime.Today.AddMonths(1);

        else if(date_type == "CQS")

            baseDate = DateTime.Today.AddMonths(1);

        else if(date_type == "CQE")

            baseDate = DateTime.Today.AddMonths(1);

        else if(date_type == "CYS")

            baseDate = DateTime.Today.AddMonths(1);

        else if(date_type == "CYE")

            baseDate = DateTime.Today.AddMonths(1);

        else if(date_type == "PMS")

            baseDate = DateTime.Today.AddMonths(-1);

        else if(date_type == "PME")

            baseDate = DateTime.Today.AddMonths(-1);

        else if(date_type == "PQS")

            baseDate = DateTime.Today.AddMonths(-1);

        else if(date_type == "PQE")

            baseDate = DateTime.Today.AddMonths(-1);

        else if(date_type == "PYS")

            baseDate = DateTime.Today.AddMonths(-1);

        else if(date_type == "PYE")

            baseDate = DateTime.Today.AddMonths(-1);

        DateTime Date = (DateTime)baseDate;

        return Date;

    }

}