public void PlayAGame()
{
TicTacToeBot ai = new TicTacToeBot();
TicTacToeBoard board = new TicTacToeBoard();
Random rng = new Random();
bool yourTurn;
Console.WriteLine("Randomizing who starts...");
if (rng.Next(2) == 0)
{
Console.WriteLine("You start!");
yourTurn = true;
}
else
{
Console.WriteLine("AI starts.");
yourTurn = false;
}
int winner = 0;
bool draw = false;
while (winner == 0 && !draw)
{
if (yourTurn)
{
TakeATurn(board);
}
else
{
board.MakeMove(ai.GetBestMove(board), 1);
}
yourTurn = !yourTurn;
winner = board.CheckForWin();
draw = board.CheckForDraw();
}
board.DisplayBoard();
if (winner == 1)
{
Console.WriteLine("AI wins.");
}
else if (winner == 2)
{
Console.WriteLine("You win!");
}
else
{
Console.WriteLine("Draw game.");
}
}
public double AlphaBeta(TicTacToeBoard oldBoard, double alpha, double beta, int player)
{
if (oldBoard.CheckForWin() != 0 || oldBoard.CheckForDraw())
{
return Score(oldBoard);
}
if (player == 1)
{
double val = -10000.0;
for (int i = 1; i <= 9; i++)
{
if (oldBoard.GetMove(i) == 0)
{
TicTacToeBoard newBoard = new TicTacToeBoard(oldBoard);
newBoard.MakeMove(i, player);
val = Math.Max(val, gamma * AlphaBeta(newBoard, alpha, beta, 2));
alpha = Math.Max(alpha, val);
if (beta <= alpha) break;
}
}
return alpha;
}
else
{
double val = 10000.0;
for (int i = 1; i <= 9; i++)
{
if (oldBoard.GetMove(i) == 0)
{
TicTacToeBoard newBoard = new TicTacToeBoard(oldBoard);
newBoard.MakeMove(i, player);
val = Math.Min(val, gamma * AlphaBeta(newBoard, alpha, beta, 1));
beta = Math.Min(val, beta);
if (beta <= alpha) break;
}
}
return beta;
}
}
