public Tuple <Move, int> runMinMax(Board board, string activePlayer, uint depth, bool max, int alpha, int beta, putScore put)
{
// Prints number of searched moves
put(1);
string nonActivePlayer = "";
if (activePlayer == "white")
{
nonActivePlayer = "black";
}
else
{
nonActivePlayer = "white";
}
// First check if this is leaf node
if (depth <= 0)
{
return(new Tuple <Move, int>(null, (max ? board.getScore(activePlayer) : board.getScore(nonActivePlayer))));
}
// Not a leaf node, branch out
List <Move> moves = new List <Move>();
// Get moves from active player
if (activePlayer == "white")
{
moves = ChessForms.rules.Rules.getWhiteMoves(board);
}
else
{
moves = ChessForms.rules.Rules.getBlackMoves(board);
}
// Check if no legal moves
if (moves.Count == 0)
{
return(new Tuple <Move, int>(null, (max ? MINIMUM : MAXIMUM)));
}
// Assume horrible best
int bestScore = (max ? MINIMUM : MAXIMUM);
Tuple <Move, int> bestResult = new Tuple <Move, int>(null, bestScore);
// Loop through all moves and minmax them
Board nextBoard = new Board(board.getTurn());
Tuple <Move, int> nextResult;
foreach (Move move in moves)
{
nextBoard.Copy(board);
nextBoard.makeMove(activePlayer, move);
nextResult = runMinMax(nextBoard, nonActivePlayer, depth - 1, !max, alpha, beta, put);
// If new best result, then change bestResult.
if ((nextResult.Item2 > bestResult.Item2 && max) ||
(nextResult.Item2 < bestResult.Item2 && !max))
{
bestResult = new Tuple <Move, int>(move, nextResult.Item2);
}
// Alpha-Beta pruning
if (max)
{
alpha = Math.Max(alpha, bestResult.Item2);
}
else
{
beta = Math.Min(beta, bestResult.Item2);
}
if (beta <= alpha)
{
// Need not explore subtree.
break;
}
// Run events to not stall the entire application while searching.
Application.DoEvents();
}
return(bestResult);
}
public Tuple<Move, int> runMinMax(Board board, string activePlayer, uint depth, bool max, int alpha, int beta, putScore put)
{
// Prints number of searched moves
put(1);
string nonActivePlayer = "";
if (activePlayer == "white")
{
nonActivePlayer = "black";
}
else
{
nonActivePlayer = "white";
}
// First check if this is leaf node
if (depth <= 0)
{
return new Tuple<Move, int>(null, (max ? board.getScore(activePlayer) : board.getScore(nonActivePlayer)));
}
// Not a leaf node, branch out
List<Move> moves = new List<Move>();
// Get moves from active player
if (activePlayer == "white")
{
moves = ChessForms.rules.Rules.getWhiteMoves(board);
}
else
{
moves = ChessForms.rules.Rules.getBlackMoves(board);
}
// Check if no legal moves
if (moves.Count == 0)
{
return new Tuple<Move, int>(null, (max ? MINIMUM : MAXIMUM));
}
// Assume horrible best
int bestScore = (max ? MINIMUM : MAXIMUM);
Tuple<Move, int> bestResult = new Tuple<Move, int>(null, bestScore);
// Loop through all moves and minmax them
Board nextBoard = new Board(board.getTurn());
Tuple<Move, int> nextResult;
foreach (Move move in moves)
{
nextBoard.Copy(board);
nextBoard.makeMove(activePlayer, move);
nextResult = runMinMax(nextBoard, nonActivePlayer, depth - 1, !max, alpha, beta, put);
// If new best result, then change bestResult.
if ((nextResult.Item2 > bestResult.Item2 && max) ||
(nextResult.Item2 < bestResult.Item2 && !max))
{
bestResult = new Tuple<Move, int>(move, nextResult.Item2);
}
// Alpha-Beta pruning
if (max)
{
alpha = Math.Max(alpha, bestResult.Item2);
}
else
{
beta = Math.Min(beta, bestResult.Item2);
}
if (beta <= alpha)
{
// Need not explore subtree.
break;
}
// Run events to not stall the entire application while searching.
Application.DoEvents();
}
return bestResult;
}
