/// <summary>
/// Cắt tỉa Alpha - Beta
/// </summary>
/// <param name="board">thế cờ hiện tại</param>
/// <param name="alpha">giá trị âm vô cùng</param>
/// <param name="beta">giá trị dương vô cùng</param>
/// <param name="depth">độ sâu tìm kiếm</param>
/// <param name="player">người chơi 1 là Max, -1 là Min</param>
/// <returns></returns>
///
public Computer AlphaBetaPruning(ChessBoard board, int alpha, int beta, int depth, int player)
{
Computer com = new Computer();
if (depth == 0 || board.CheckWinNegativeTeam() || board.CheckWinPositiveTeam())
{
com.Value = board.Value;
com.Board = board.Clone();
return com;
}
if (player == 1)
{
foreach (var b in GenerateBoardPositiveTeam(board))
{
int temp = AlphaBetaPruning(b, alpha, beta, depth - 1, -1).Value;
//Debug.WriteLine("temp1 = {0}, alpha = {1}, depth = {2}", temp, alpha, depth);
i++;
if (temp > alpha)
{
alpha = temp;
com.Value = alpha;
com.Board = b.Clone();
}
if (beta <= alpha) return com;
}
return com;
}
else
{
foreach (var b in GenerateBoardNegativeTeam(board))
{
int temp = AlphaBetaPruning(b, alpha, beta, depth - 1, 1).Value;
i++;
//Debug.WriteLine("temp2 = {0}, beta = {1}, depth = {2}", temp, beta, depth);
if (temp < beta)
{
beta = temp;
com.Board = b.Clone();
com.Value = beta;
}
if (beta <= alpha) return com;
}
return com;
}
}
/// <summary>
/// Allows the game to perform any initialization it needs to before starting to run.
/// This is where it can query for any required services and load any non-graphic
/// related content. Calling base.Initialize will enumerate through any components
/// and initialize them as well.
/// </summary>
protected override void Initialize()
{
// TODO: Add your initialization logic here
board = new ChessBoard();
btnUndo = new Entity(Content.Load<Texture2D>("undo"), new Vector2(0, 650));
computer = new Computer();
base.Initialize();
}
public ChessBoard GetNextBoard(ChessBoard board)
{
Computer com = new Computer();
i = 0;
com = AlphaBetaPruning(board, -10000, 10000, 5, 1);
Debug.WriteLine("Count = " + i);
return com.Board;
}