Mentor Group

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;

namespace _08_MentorGroup
{
    class MentorGroup
    {
        static void Main(string[] args)
        {
            Dictionary<string, Mentor> mentors = new Dictionary<string, Mentor>();

            while (true)
            {
                string[] input = Console.ReadLine()
                .Split(new char[] { ' ', ',' }, StringSplitOptions.RemoveEmptyEntries);
                if (input[0] == "end" && input[1] == "of" && input[2] == "dates")
                {
                    break;
                }

                string name = input[0];
                if (!mentors.ContainsKey(name))
                {
                    mentors.Add(name, new Mentor());
                }

                for (int i = 1; i < input.Length; i++)
                {
                    mentors[name].Attendances.Add(DateTime.ParseExact(input[i], "dd/MM/yyyy", DateTimeFormatInfo.InvariantInfo));
                }
            }

            while (true)
            {
                string[] input = Console.ReadLine()
                .Split(new char[] { '-' }, StringSplitOptions.RemoveEmptyEntries);
                if (input[0] == "end of comments")
                {
                    break;
                }

                string name = input[0];
                if (mentors.ContainsKey(name))
                {
                    mentors[name].Comments.Add(input[1]);
                }
            }

            foreach (var mentor in mentors.OrderBy(x => x.Key))
            {
                Console.WriteLine(mentor.Key);
                Console.WriteLine("Comments:");
                foreach (string comment in mentor.Value.Comments)
                {
                    Console.WriteLine($"- {comment}");
                }
                Console.WriteLine("Dates attended:");
                foreach (DateTime date in mentor.Value.Attendances.OrderBy(x => x))
                {
                    Console.WriteLine($"-- {date:dd/MM/yyyy}");
                }
            }
        }
    }

    class Mentor
    {
        public List<string> Comments;
        public List<DateTime> Attendances;

        public Mentor()
        {
            Comments = new List<string>();
            Attendances = new List<DateTime>();
        }
    }
}