title: At least one object must implement IComparable
body: <pre><code>using System;
  using System.Xml;
  using System.Collections.Generic;
  using System.Linq;
  using System.Text;
  
  namespace ConsoleApplication1
  {
      class Program
      {
          static void Main(string[] args)
          {
              SortedSet&lt;Player&gt; PlayerList = new SortedSet&lt;Player&gt;();
  
              while (true)
              {
                  string Input;
                  Console.WriteLine("What would you like to do?");
                  Console.WriteLine("1. Create new player and score.");
                  Console.WriteLine("2. Display Highscores.");
                  Console.WriteLine("3. Write out to XML file.");
                  Console.Write("Input Number: ");
                  Input = Console.ReadLine();
                  if (Input == "1")
                  {
                      Player player = new Player();
                      string PlayerName;
                      string Score;
  
                      Console.WriteLine();
                      Console.WriteLine("-=CREATE NEW PLAYER=-");
                      Console.Write("Player name: ");
                      PlayerName = Console.ReadLine();
                      Console.Write("Player score: ");
                      Score = Console.ReadLine();
  
                      player.Name = PlayerName;
                      player.Score = Convert.ToInt32(Score);
  
                      //====================================
                      //ERROR OCCURS HERE
                      //====================================
                      PlayerList.Add(player);
  
  
                      Console.WriteLine("Player \"" + player.Name + "\" with the score of \"" + player.Score + "\" has been created successfully!" );
                      Console.WriteLine();
                  }
                  else
                  {
                      Console.WriteLine("INVALID INPUT");
                  }
              }
          }
      }
  }
  </code></pre>
  
  <p>So i keep getting the "</p>
  
  <blockquote>
    <p>At least one object must implement IComparable.</p>
  </blockquote>
  
  <p>" when trying to add a second player, the first one works, but the second one doesn't.
  I also MUST use <code>SortedSet</code> because that is the requirement for the work, it's school work.</p>