// Prompt the user for input, displaying an error message if the previous input was invalid.
private string RequestInput(bool error)
{
Console.Clear();
Console.WriteLine(board.GetBoardAsString());
if (error)
{
Console.WriteLine("That was not a valid move. Please try again.");
}
Console.WriteLine($"{(turn ? "White" : "Black")}, type \"EXIT\" to end the game, or enter the cell in which to place your next piece (for example, \"I9\"):");
return(Console.ReadLine());
}