using System;

using System.Collections;

using System.Collections.Generic;

public class Program

{

        class Client

        {

        private static int counter;

        private static Random rand = new Random();

        public int Number

        {

          get;private set;

        }

          public int ServiceTime

          {

            get;private set;

          }

            public Client()

        {

           counter++;

           Number = counter;

           ServiceTime = rand.Next(1, 5);

        }

​

        }

    public static void Main()

    {

        Queue<Client> clients = new Queue<Client>();

        int totalTime = 0;

        while (true)

        {

          string input = Console.ReadLine();

          if (input == "exit")

          {

            break;

          }

            else if(input == "add")

            {

              Client client = new Client ();

              clients.Enqueue(client);

               Console.WriteLine("Client {0} added to queue, Estimated wait time: {1} minutes", client.Number,client.ServiceTime);

            }

            else if(input=="next")

            {

              if(clients.Count==0)

              {

              Console.WriteLine("no clients on queue");

              }

                else

                {

                Client currentClient = new Client();

                totalTime += currentClient.ServiceTime;

                     Console.WriteLine("Client {0} Served time {1} minutes", currentClient.Number, currentClient.ServiceTime);

                }

            }

            else if(input == "count")

            {

               Console.WriteLine("Count of clients on queue is {0} ", clients.Count);

               Console.WriteLine("Total wait time: {0} ", totalTime + " Minutes");

            }

            else

            {

            Console.WriteLine("Invalid command ! ");

            }

        }

    }

}