RoliTheCoder

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

namespace RoliTheCoder
{
    class Program
    {
        static void Main(string[] args)
        {
            var input = Console.ReadLine();

            var eventId = new Dictionary<int, string>();
            var eventParticipands = new Dictionary<string, HashSet<string>>();

            while (input != "Time for Code")
            {
                var info = input.Split(new char[] { ' ' },StringSplitOptions.RemoveEmptyEntries).ToList();

                if (info[1].StartsWith("#"))
                {
                    var id = int.Parse(info[0]);
                    string eventName = info[1].Substring(1);
                    var participants = info.Skip(2).ToList();

                    if (eventId.ContainsKey(id)==false)
                    {
                        eventId.Add(id, eventName);
                        eventParticipands.Add(eventName, new HashSet<string>());
                    }

                    if (eventId.ContainsKey(id) && eventId[id]==eventName)
                    {

                        foreach (var participand in participants)
                        {
                            eventParticipands[eventName].Add(participand);
                        }
                    }


                }
                input = Console.ReadLine();
            }

            foreach (var eventName in eventParticipands.OrderByDescending(x=>x.Value.Count()).ThenBy(x=>x.Key))
            {
                Console.WriteLine($"{eventName.Key} - {eventName.Value.Count()}");

                foreach (var item in eventName.Value.OrderBy(x=>x))
                {
                    Console.WriteLine(item);
                }

            }

        }
    }
}