public Move MinMaxRoot(int depth, Game g, bool IsMaximizingPlayer)
{
MoveGenerationResult result = g.GetMoves();
count += result.Moves.Count;
if (result.Endgame == EndgameType.Checkmate)
{
throw new CheckmateException();
}
else if (result.Endgame == EndgameType.Stalemate)
{
throw new StalemateException();
}
double bestMove = -999999 * (g.WhiteToMove ? 1 : -1);
Random r = new Random();
Move bestMoveFound = result.Moves[r.Next(result.Moves.Count - 1)];
string FENFEN = g.ToFENString();
var exceptions = new ConcurrentQueue <Exception>();
ConcurrentBag <Tuple <Move, double> > resultVal = new ConcurrentBag <Tuple <Models.Move, double> >();
Parallel.ForEach(result.Moves, (move) =>
{
Game g2 = new Game(FENFEN);
move = g2.Move(move);
try
{
double value = MiniMax(depth - 1, g2, -1000000, 1000000, !IsMaximizingPlayer, move.To);
resultVal.Add(new Tuple <Move, double>(move, value));
}
catch (Exception w)
{
exceptions.Enqueue(w);
}
g2.Undo();
});
if (exceptions.Count > 0 && resultVal.Count == 0)
{
Exception ex;
exceptions.TryDequeue(out ex);
throw ex;
}
foreach (Tuple <Move, double> moveTuple in resultVal)
{
if ((g.WhiteToMove && (moveTuple.Item1.MaterialScore >= bestMove)) || (!g.WhiteToMove && (moveTuple.Item1.MaterialScore <= bestMove)))
{
bestMove = moveTuple.Item2;
bestMoveFound = moveTuple.Item1;
}
}
return(bestMoveFound);
}
public double MiniMax(int depth, Game g, double alpha, double beta, bool IsMaximizingPlayer, int thisMove)
{
if (depth == 0)
{
return(g.BoardValue());
}
MoveGenerationResult result = g.GetMoves();
if (result.Endgame == EndgameType.Checkmate)
{
if (g.WhiteToMove)
{
return(-10000000);
}
else
{
return(10000000);
}
}
if (result.Endgame == EndgameType.Stalemate)
{
if (g.WhiteToMove)
{
return(10000000);
}
else
{
return(-10000000);
}
}
count += result.Moves.Count;
if (g.WhiteToMove)
{
double bestMove = -999999;
foreach (Move move in result.Moves)
{
g.Move(move);
bestMove = Math.Max(bestMove, MiniMax(depth - 1, g, alpha, beta, !IsMaximizingPlayer, move.To));
g.Undo();
alpha = Math.Max(alpha, bestMove);
if (beta <= alpha)
{
return(bestMove);
}
}
return(bestMove);
}
else
{
double bestMove = 999999;
foreach (Move move in result.Moves)
{
g.Move(move);
bestMove = Math.Min(bestMove, MiniMax(depth - 1, g, alpha, beta, !IsMaximizingPlayer, move.To));
g.Undo();
beta = Math.Min(beta, bestMove);
if (beta <= alpha)
{
return(bestMove);
}
}
return(bestMove);
}
}