حالا می خواسم همین پروژه رو با الگوریتم Minimax بدون بهینه سازی با جستجوی حریصانه آلفا-بتا پیاده سازی کنم. متد مربوط به پیاده سازی این الگوریتم به شکل کد زیر هست
private ComputerMove GetBestMove(Board board, int color, int depth, int alpha, int beta)
{
// Initialize the best move.
ComputerMove bestMove = new ComputerMove(-1, -1);
bestMove.rank = -color * Reversi.maxRank;
// Find out how many valid moves we have so we can initialize the
// mobility score.
int validMoves = movement.GetValidMoveCount(color);
// Start at a random position on the board. This way, if two or
// more moves are equally good, we'll take one of them at random.
Random random = new Random();
int rowStart = random.Next(8);
int colStart = random.Next(8);
// Check all valid moves.
int i, j;
for (i = 0; i < 8; i++)
for (j = 0; j < 8; j++)
{
// Get the row and column.
int row = (rowStart + i) % 8;
int col = (colStart + j) % 8;
if (movement.IsValidMove(color, row, col))
{
// Make the move.
ComputerMove testMove = new ComputerMove(row, col);
Board testBoard = new Board(board);
Movement testMovement=new Movement(testBoard);
testMovement.MakeMove(color, testMove.row, testMove.col);
int score = testBoard.WhiteCount - testBoard.BlackCount;
// Check the board.
int nextColor = -color;
int forfeit = 0;
bool isEndGame = false;
int opponentValidMoves = testMovement.GetValidMoveCount(nextColor);
if (opponentValidMoves == 0)
{
// The opponent cannot move, count the forfeit.
forfeit = color;
// Switch back to the original color.
nextColor = -nextColor;
// If that player cannot make a move either, the
// game is over.
if (testMovement.GetValidMoveCount(nextColor)==0)
isEndGame = true;
}
// If we reached the end of the look ahead (end game or
// max depth), evaluate the board and set the move
// rank.
if (isEndGame || depth == this.lookAheadDepth)
{
// For an end game, max the ranking and add on the
// final score.
if (isEndGame)
{
// Negative value for black win.
if (score < 0)
testMove.rank = -Reversi.maxRank + score;
// Positive value for white win.
else if (score > 0)
testMove.rank = Reversi.maxRank + score;
// Zero for a draw.
else
testMove.rank = 0;
}
// It's not an end game so calculate the move rank.
else
testMove.rank =
this.forfeitWeight * forfeit +
this.frontierWeight * (testBoard.BlackFrontierCount - testBoard.WhiteFrontierCount) +
this.mobilityWeight * color * (validMoves - opponentValidMoves) +
this.stabilityWeight * (testBoard.WhiteSafeCount - testBoard.BlackSafeCount) +
score;
}
// Otherwise, perform a look ahead.
else
{
ComputerMove nextMove = this.GetBestMove(testBoard, nextColor, depth + 1, alpha, beta);
// Pull up the rank.
testMove.rank = nextMove.rank;
// Forfeits are cumulative, so if the move did not
// result in an end game, add any current forfeit
// value to the rank.
if (forfeit != 0 && Math.Abs(testMove.rank) < Reversi.maxRank)
testMove.rank += forfeitWeight * forfeit;
// Adjust the alpha and beta values, if necessary.
//computer is white
if (color == Board.White && testMove.rank > beta)
beta = testMove.rank;
if (color == Board.Black && testMove.rank < alpha)
alpha = testMove.rank;
}
// Perform a cutoff if the rank is outside tha alpha-beta range.
if (color == Board.White && testMove.rank > alpha)
{
testMove.rank = alpha;
return testMove;
}
if (color == Board.Black && testMove.rank < beta)
{
testMove.rank = beta;
return testMove;
}
// If this is the first move tested, assume it is the
// best for now.
if (bestMove.row < 0)
bestMove = testMove;
// Otherwise, compare the test move to the current
// best move and take the one that is better for this
// color.
else if (color * testMove.rank > color * bestMove.rank)
bestMove = testMove;
}
}
// Return the best move found.
return bestMove;
}
حالا چه تغییراتی رو باید در این کد اعمال کنم تا تبدیل به Minimax استاندارد بشه
اگر کمکم کنید ممنون می شم
پیاده سازی بازی Reversi با الگوریتم Minimax
پاسخ با نقل قول