9.ForceBook

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

namespace RegularExpressions
{
    class Program
    {
        static void Main(string[] args)
        {
            Dictionary<string, List<string>> forceSideUsers =
                new Dictionary<string, List<string>>();


            while (true)
            {
                string input = Console.ReadLine();

                if (input=="Lumpawaroo")
                {
                    break;
                }
                else
                {
                    if (input.Contains("|"))
                    {
                        string[] forceBook = input.Split(" | ");

                        string forceSide = forceBook[0];
                        string forceUser = forceBook[1];

                        if (!forceSideUsers.ContainsKey(forceSide))
                        {
                            forceSideUsers.Add(forceSide, new List<string>());
                        }

                        if (!forceSideUsers[forceSide].Contains(forceUser))
                        {
                            forceSideUsers[forceSide].Add(forceUser);
                        }

                    }
                    else
                    {
                        string[] forceBook = input.Split(" -> ");

                        string forceSide = forceBook[1];
                        string forceUser = forceBook[0];

                        if (forceSideUsers.ContainsKey(forceSide))
                        {
                            if (!forceSideUsers[forceSide].Contains(forceUser))
                            {
                                forceSideUsers[forceSide].Add(forceUser);
                                Console.WriteLine($"{forceUser} joins the {forceSide} side!");
                            }
                            else
                            {
                                forceSideUsers[forceSide].Remove(forceUser);
                            }
                        }
                    }


                }
            }

            foreach (var kvp in forceSideUsers)
            {
                Console.WriteLine($"Side: {kvp.Key}, Members: {kvp.Value.Count}");

                foreach (var user in kvp.Value)
                {
                    Console.WriteLine($"! {user}");
                }
            }
        }
    }
}