private void IterativeDeepening_OnSearchUpdate(object sender, SearchStatistics statistics)
{
// Main search result
_interactiveConsole.WriteLine($" === Depth: {statistics.Depth}, Score: {statistics.Score}, Best: {statistics.PrincipalVariation[0]}, " +
$"Time: {((float) statistics.SearchTime / 1000):F} s");
// Normal search
_interactiveConsole.WriteLine($" Normal search: Nodes: {statistics.Nodes}, Leafs: {statistics.Leafs}, " +
$"Branching factor: {statistics.BranchingFactor:F}, Beta cutoffs: {statistics.BetaCutoffs}");
// Quiescence search
_interactiveConsole.WriteLine($" Q search: Nodes: {statistics.QNodes}, Leafs: {statistics.QLeafs}, " +
$"Branching factor: {statistics.QBranchingFactor:F}, Beta cutoffs: {statistics.QBetaCutoffs}");
// Total
_interactiveConsole.WriteLine($" Total: Nodes: {statistics.TotalNodes} ({((float)statistics.TotalNodesPerSecond / 1000000):F} MN/s), " +
$"Leafs: {statistics.TotalLeafs}, Branching factor: {statistics.TotalBranchingFactor:F}, " +
$"Beta cutoffs: {statistics.TotalBetaCutoffs}");
#if DEBUG
// Beta cutoffs at first move
_interactiveConsole.WriteLine($" Beta cutoffs at first move: {statistics.BetaCutoffsAtFirstMove} ({statistics.BetaCutoffsAtFirstMovePercent:F} %), " +
$"Q Beta cutoffs at first move: {statistics.QBetaCutoffsAtFirstMove} ({statistics.QBetaCutoffsAtFirstMovePercent:F} %)");
// Transposition statistics
_interactiveConsole.WriteLine($" TT: " +
$"Added: {statistics.TTAddedEntries}, " +
$"Replacements: {statistics.TTReplacements} ({statistics.TTReplacesPercent:F} %), " +
$"Hits: {statistics.TTHits} ({statistics.TTHitsPercent:F} %), " +
$"Missed: {statistics.TTNonHits}, " +
$"Filled: {TranspositionTable.GetFillLevel():F} %");
// Pawn hash table statistics
_interactiveConsole.WriteLine($" PHT: " +
$"Added: {statistics.EvaluationStatistics.PHTAddedEntries}, " +
$"Replacements: {statistics.EvaluationStatistics.PHTReplacements} ({statistics.EvaluationStatistics.PHTReplacesPercent:F} %), " +
$"Hits: {statistics.EvaluationStatistics.PHTHits} ({statistics.EvaluationStatistics.PHTHitsPercent:F} %), " +
$"Missed: {statistics.EvaluationStatistics.PHTNonHits}, " +
$"Filled: {PawnHashTable.GetFillLevel():F} %");
// Evaluation hash table statistics
_interactiveConsole.WriteLine($" EHT: " +
$"Added: {statistics.EvaluationStatistics.EHTAddedEntries}, " +
$"Replacements: {statistics.EvaluationStatistics.EHTReplacements} ({statistics.EvaluationStatistics.EHTReplacesPercent:F} %), " +
$"Hits: {statistics.EvaluationStatistics.EHTHits} ({statistics.EvaluationStatistics.EHTHitsPercent:F} %), " +
$"Missed: {statistics.EvaluationStatistics.EHTNonHits}, " +
$"Filled: {EvaluationHashTable.GetFillLevel():F} %");
_interactiveConsole.WriteLine($" Valid TT moves: {statistics.TTValidMoves}, Invalid TT moves: {statistics.TTInvalidMoves}, " +
$"IID hits: {statistics.IIDHits}, Loud generations: {statistics.LoudMovesGenerated}, " +
$"Quiet generations: {statistics.QuietMovesGenerated}");
#endif
_interactiveConsole.WriteLine();
}
public void Run(params string[] parameters)
{
TranspositionTable.Clear();
PawnHashTable.Clear();
EvaluationHashTable.Clear();
KillerHeuristic.Clear();
HistoryHeuristic.Clear();
_uciClient.BoardState.SetDefaultState();
}
private void Test(BoardState boardState, string name, int depth)
{
_interactiveConsole.WriteLine($" == {name}:");
TranspositionTable.Clear();
PawnHashTable.Clear();
EvaluationHashTable.Clear();
KillerHeuristic.Clear();
HistoryHeuristic.Clear();
var context = new SearchContext(boardState)
{
MaxDepth = depth
};
IterativeDeepening.OnSearchUpdate += IterativeDeepening_OnSearchUpdate;
IterativeDeepening.FindBestMove(context);
IterativeDeepening.OnSearchUpdate -= IterativeDeepening_OnSearchUpdate;
_interactiveConsole.WriteLine();
}
public static int FindBestMove(SearchContext context, int depth, int ply, int alpha, int beta)
{
context.Statistics.QNodes++;
if (ply > context.Statistics.SelectiveDepth)
{
context.Statistics.SelectiveDepth = ply;
}
if (context.BoardState.Pieces[context.BoardState.ColorToMove][Piece.King] == 0)
{
context.Statistics.QLeafs++;
return(SearchConstants.NoKingValue);
}
if (context.BoardState.IsKingChecked(ColorOperations.Invert(context.BoardState.ColorToMove)))
{
context.Statistics.QLeafs++;
return(-SearchConstants.NoKingValue);
}
var standPat = 0;
var evaluationEntry = EvaluationHashTable.Get(context.BoardState.Hash);
if (evaluationEntry.IsKeyValid(context.BoardState.Hash))
{
standPat = evaluationEntry.Score;
#if DEBUG
context.Statistics.EvaluationStatistics.EHTHits++;
#endif
}
else
{
standPat = Evaluation.Evaluate(context.BoardState, true, context.Statistics.EvaluationStatistics);
EvaluationHashTable.Add(context.BoardState.Hash, (short)standPat);
#if DEBUG
context.Statistics.EvaluationStatistics.EHTNonHits++;
context.Statistics.EvaluationStatistics.EHTAddedEntries++;
if (evaluationEntry.Key != 0 || evaluationEntry.Score != 0)
{
context.Statistics.EvaluationStatistics.EHTReplacements++;
}
#endif
}
if (standPat >= beta)
{
context.Statistics.QLeafs++;
return(standPat);
}
if (standPat > alpha)
{
alpha = standPat;
}
Span <Move> moves = stackalloc Move[SearchConstants.MaxMovesCount];
Span <short> moveValues = stackalloc short[SearchConstants.MaxMovesCount];
var movesCount = context.BoardState.GetAvailableCaptureMoves(moves);
MoveOrdering.AssignQValues(context.BoardState, moves, moveValues, movesCount);
for (var moveIndex = 0; moveIndex < movesCount; moveIndex++)
{
MoveOrdering.SortNextBestMove(moves, moveValues, movesCount, moveIndex);
if (moveValues[moveIndex] < 0)
{
#if DEBUG
context.Statistics.QSEEPrunes++;
#endif
break;
}
if (standPat + moveValues[moveIndex] + SearchConstants.QFutilityPruningMargin < alpha)
{
#if DEBUG
context.Statistics.QFutilityPrunes++;
#endif
break;
}
context.BoardState.MakeMove(moves[moveIndex]);
var score = -FindBestMove(context, depth - 1, ply + 1, -beta, -alpha);
context.BoardState.UndoMove(moves[moveIndex]);
if (score > alpha)
{
alpha = score;
if (alpha >= beta)
{
#if DEBUG
if (moveIndex == 0)
{
context.Statistics.QBetaCutoffsAtFirstMove++;
}
else
{
context.Statistics.QBetaCutoffsNotAtFirstMove++;
}
#endif
context.Statistics.QBetaCutoffs++;
break;
}
}
}
return(alpha);
}