04. ForceBook

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

namespace ForceBook
{
    class Program
    {
        static void Main(string[] args)
        {
            // Users database
            Dictionary<string, string> forceUsers = new Dictionary<string, string>();
            // Sides members database
            Dictionary<string, int> sidesCount = new Dictionary<string, int>();

            while (true)
            {
                string input = Console.ReadLine();
                if (input == "Lumpawaroo") { break; }

                if (input.Contains(" | "))
                {
                    // Process input
                    string[] tokens = input.Split("|".ToCharArray(), StringSplitOptions.RemoveEmptyEntries);
                    string inputSide = tokens[0].Trim();
                    string inputUser = tokens[1].Trim();

                    // Add non-existing user
                    if (forceUsers.ContainsKey(inputUser) == false)
                    {
                        forceUsers.Add(inputUser, inputSide);

                        if (sidesCount.ContainsKey(inputSide) == false)
                        {
                            sidesCount.Add(inputSide, 0);
                        }
                        sidesCount[inputSide]++;
                    }
                }
                else if (input.Contains("->"))
                {
                    string[] tokens = input.Split("->".ToCharArray(), StringSplitOptions.RemoveEmptyEntries);
                    string inputUser = tokens[0].Trim();
                    string inputSide = tokens[1].Trim();

                    // Add non-existing user
                    if (forceUsers.ContainsKey(inputUser) == false)
                    {
                        forceUsers.Add(inputUser, inputSide);

                        // Add non-existing side
                        if (sidesCount.ContainsKey(inputSide) == false)
                        {
                            sidesCount.Add(inputSide, 0);
                        }
                        // Increment side members
                        sidesCount[inputSide]++;
                    }
                    // Update existing user's side
                    else
                    {
                        string currentSide = forceUsers[inputUser];
                        forceUsers[inputUser] = inputSide;

                        // Add non-existing side
                        if (sidesCount.ContainsKey(inputSide) == false)
                        {
                            sidesCount.Add(inputSide, 0);
                        }
                        // Increment side members
                        sidesCount[inputSide]++;
                        // Decrement former user's side
                        sidesCount[currentSide]--;
                    }

                    Console.WriteLine($"{inputUser} joins the {inputSide} side!");
                }
            }

            // Sort and print
            sidesCount = sidesCount.OrderByDescending(s => s.Value).ThenBy(s => s.Key).ToDictionary(s => s.Key, s => s.Value);
            foreach (var side in sidesCount)
            {
                if (side.Value > 0)
                {
                    Console.WriteLine($"Side: {side.Key}, Members: {side.Value}");
                    var sideUsers = forceUsers.Where(u => u.Value == side.Key).OrderBy(u => u.Key);

                    foreach (var user in sideUsers)
                    {
                        Console.WriteLine($"! {user.Key}");
                    }
                }
            }
        }
    }
}