static void Main(string[] args) { // This class should be treated as read-only for your purposes, but feel free to see how it works Board game = new Board(); int player = 2; while (!game.IsWinningBoard() && !game.IsCatsGame()) { player = player % 2 + 1; // change the players Console.Out.Write("Input the square number for player " + player + "'s move: "); string squareAsString = Console.In.ReadLine(); int square; while (!Int32.TryParse(squareAsString, out square) && square >= 1 && square <= 9) { Console.Out.WriteLine("An invalid square was entered, please try again."); Console.Out.Write("Input the square number for player " + player + "'s move: "); squareAsString = Console.In.ReadLine(); } game.PrintBoard(); } if (game.IsWinningBoard()) { Console.Out.WriteLine("Player " + player + " is the winner!"); } else { Console.Out.WriteLine("Cat's game!"); } Console.ReadKey(); // stop the console from closing automatically }