using System;

using System.Collections.Generic;               

public class Program

{

    static TimeSpan  TimeLeft;

    static Dictionary<string, DateTime> flightSchedule = new Dictionary<string, DateTime>(){

                                                        {"ZW346", Convert.ToDateTime("03:54:10")},

                                                        {"AT489", Convert.ToDateTime("16:30:00")},

                                                        {"CT489", Convert.ToDateTime("23:30:00")},

                                                        {"BR267", Convert.ToDateTime("21:15:30")}};

    public static string flightStatus(string flightNo)

    {

        if(flightSchedule.ContainsKey(flightNo))

        {

            if(DateTime.Now < flightSchedule[flightNo])

            {

                TimeLeft = flightSchedule[flightNo] - DateTime.Now;

                //Console.WriteLine(DateTime.UtcNow);

                return "Time To Flight "+TimeLeft.ToString();

            }

            else

            {

                return "Flight Already Left";

            }

        }

        else

        {

            return "Invalid";

        }

    }

    public static void Main()

    {

        Console.WriteLine("Enter the Flight Number : ");

        string FlightNumber = Console.ReadLine();

        Console.WriteLine(Program.flightStatus(FlightNumber));

    }

}