lkarch.org/tools/mathisfun/www.mathsisfun.com/games/images/garbochess.js

"use strict";var g_debug=true;var g_timeout=40;var rp_ply=99;var rp_rand='n';function GetFen(){var result="";for(var row=0;row<8;row++){if(row!=0)
result+='../index.html';var empty=0;for(var col=0;col<8;col++){var piece=g_board[((row+2)<<4)+col+4];if(piece==0){empty++;}else{if(empty!=0)
result+=empty;empty=0;var pieceChar=[" ","p","n","b","r","q","k"," "][(piece&0x7)];result+=((piece&colorWhite)!=0)?pieceChar.toUpperCase():pieceChar;}}
if(empty!=0){result+=empty;}}
result+=g_toMove==colorWhite?" w":" b";result+=" ";if(g_castleRights==0){result+="-";}else{if((g_castleRights&1)!=0)
result+="K";if((g_castleRights&2)!=0)
result+="Q";if((g_castleRights&4)!=0)
result+="k";if((g_castleRights&8)!=0)
result+="q";}
result+=" ";if(g_enPassentSquare==-1){result+='-';}else{result+=FormatSquare(g_enPassentSquare);}
return result;}
function GetMoveSAN(move,validMoves){var from=move&0xFF;var to=(move>>8)&0xFF;if(move&moveflagCastleKing)return "O-O";if(move&moveflagCastleQueen)return "O-O-O";var pieceType=g_board[from]&0x7;var result=["","","N","B","R","Q","K",""][pieceType];var dupe=false,rowDiff=true,colDiff=true;if(validMoves==null){validMoves=GenerateValidMoves();}
for(var i=0;i<validMoves.length;i++){var moveFrom=validMoves[i]&0xFF;var moveTo=(validMoves[i]>>8)&0xFF;if(moveFrom!=from&&moveTo==to&&(g_board[moveFrom]&0x7)==pieceType){dupe=true;if((moveFrom&0xF0)==(from&0xF0)){rowDiff=false;}
if((moveFrom&0x0F)==(from&0x0F)){colDiff=false;}}}
if(dupe){if(colDiff){result+=FormatSquare(from).charAt(0);}else if(rowDiff){result+=FormatSquare(from).charAt(1);}else{result+=FormatSquare(from);}}else if(pieceType==piecePawn&&(g_board[to]!=0||(move&moveflagEPC))){result+=FormatSquare(from).charAt(0);}
if(g_board[to]!=0||(move&moveflagEPC)){result+="x";}
result+=FormatSquare(to);if(move&moveflagPromotion){if(move&moveflagPromoteBishop)result+="=B";else if(move&moveflagPromoteKnight)result+="=N";else if(move&moveflagPromoteQueen)result+="=Q";else result+="=R";}
MakeMove(move);if(g_inCheck){result+=GenerateValidMoves().length==0?"#":"+";}
UnmakeMove(move);return result;}
function FormatSquare(square){var letters=['a','b','c','d','e','f','g','h'];return letters[(square&0xF)-4]+((9-(square>>4))+1);}
function FormatMove(move){var result=FormatSquare(move&0xFF)+FormatSquare((move>>8)&0xFF);if(move&moveflagPromotion){if(move&moveflagPromoteBishop)result+="b";else if(move&moveflagPromoteKnight)result+="n";else if(move&moveflagPromoteQueen)result+="q";else result+="r";}
return result;}
function GetMoveFromString(moveString){var moves=GenerateValidMoves();for(var i=0;i<moves.length;i++){if(FormatMove(moves[i])==moveString){return moves[i];}}
console.log("busted! ->"+moveString+" fen:"+GetFen());}
function PVFromHash(move,ply){if(ply==0)
return "";if(move==0){if(g_inCheck)return "checkmate";return "stalemate";}
var pvString=" "+GetMoveSAN(move);MakeMove(move);var hashNode=g_hashTable[g_hashKeyLow&g_hashMask];if(hashNode!=null&&hashNode.lock==g_hashKeyHigh&&hashNode.bestMove!=null){pvString+=PVFromHash(hashNode.bestMove,ply-1);}
UnmakeMove(move);return pvString;}
var g_startTime;var g_nodeCount;var g_qNodeCount;var g_searchValid;var g_globalPly=0;function Search(finishMoveCallback,maxPly,finishPlyCallback){var lastEval;var alpha=minEval;var beta=maxEval;g_globalPly++;g_nodeCount=0;g_qNodeCount=0;g_searchValid=true;var bestMove=0;var value;g_startTime=(new Date()).getTime();var i;for(i=1;i<=maxPly&&g_searchValid;i++){var tmp=AlphaBeta(i,0,alpha,beta);if(!g_searchValid)break;value=tmp;if(value>alpha&&value<beta){alpha=value-500;beta=value+500;if(alpha<minEval)alpha=minEval;if(beta>maxEval)beta=maxEval;}else if(alpha!=minEval){alpha=minEval;beta=maxEval;i--;}
if(g_hashTable[g_hashKeyLow&g_hashMask]!=null){bestMove=g_hashTable[g_hashKeyLow&g_hashMask].bestMove;}
if(finishPlyCallback!=null){finishPlyCallback(bestMove,value,(new Date()).getTime()-g_startTime,i);}}
if(finishMoveCallback!=null){if(rp_rand=='y'){var moves=GenerateValidMoves();bestMove=moves[Math.floor(Math.random()*moves.length)];console.log("*********** garbo random move",bestMove,moves);}
finishMoveCallback(bestMove,value,(new Date()).getTime()-g_startTime,i-1);}}
var minEval=-2000000;var maxEval=+2000000;var minMateBuffer=minEval+2000;var maxMateBuffer=maxEval-2000;var materialTable=[0,800,3350,3450,5000,9750,600000];var pawnAdj=[0,0,0,0,0,0,0,0,-25,105,135,270,270,135,105,-25,-80,0,30,176,176,30,0,-80,-85,-5,25,175,175,25,-5,-85,-90,-10,20,125,125,20,-10,-90,-95,-15,15,75,75,15,-15,-95,-100,-20,10,70,70,10,-20,-100,0,0,0,0,0,0,0,0];var knightAdj=[-200,-100,-50,-50,-50,-50,-100,-200,-100,0,0,0,0,0,0,-100,-50,0,60,60,60,60,0,-50,-50,0,30,60,60,30,0,-50,-50,0,30,60,60,30,0,-50,-50,0,30,30,30,30,0,-50,-100,0,0,0,0,0,0,-100,-200,-50,-25,-25,-25,-25,-50,-200];var bishopAdj=[-50,-50,-25,-10,-10,-25,-50,-50,-50,-25,-10,0,0,-10,-25,-50,-25,-10,0,25,25,0,-10,-25,-10,0,25,40,40,25,0,-10,-10,0,25,40,40,25,0,-10,-25,-10,0,25,25,0,-10,-25,-50,-25,-10,0,0,-10,-25,-50,-50,-50,-25,-10,-10,-25,-50,-50];var rookAdj=[-60,-30,-10,20,20,-10,-30,-60,40,70,90,120,120,90,70,40,-60,-30,-10,20,20,-10,-30,-60,-60,-30,-10,20,20,-10,-30,-60,-60,-30,-10,20,20,-10,-30,-60,-60,-30,-10,20,20,-10,-30,-60,-60,-30,-10,20,20,-10,-30,-60,-60,-30,-10,20,20,-10,-30,-60];var kingAdj=[50,150,-25,-125,-125,-25,150,50,50,150,-25,-125,-125,-25,150,50,50,150,-25,-125,-125,-25,150,50,50,150,-25,-125,-125,-25,150,50,50,150,-25,-125,-125,-25,150,50,50,150,-25,-125,-125,-25,150,50,50,150,-25,-125,-125,-25,150,50,150,250,75,-25,-25,75,250,150];var emptyAdj=[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,];var pieceSquareAdj=new Array(8);var flipTable=new Array(256);function PawnEval(color){var pieceIdx=(color|1)<<4;var from=g_pieceList[pieceIdx++];while(from!=0){from=g_pieceList[pieceIdx++];}}
function Mobility(color){var result=0;var from,to,mob,pieceIdx;var enemy=color==8?0x10:0x8
var mobUnit=color==8?g_mobUnit[0]:g_mobUnit[1];mob=-3;pieceIdx=(color|2)<<4;from=g_pieceList[pieceIdx++];while(from!=0){mob+=mobUnit[g_board[from+31]];mob+=mobUnit[g_board[from+33]];mob+=mobUnit[g_board[from+14]];mob+=mobUnit[g_board[from-14]];mob+=mobUnit[g_board[from-31]];mob+=mobUnit[g_board[from-33]];mob+=mobUnit[g_board[from+18]];mob+=mobUnit[g_board[from-18]];from=g_pieceList[pieceIdx++];}
result+=65*mob;mob=-4;pieceIdx=(color|3)<<4;from=g_pieceList[pieceIdx++];while(from!=0){to=from-15;while(g_board[to]==0){to-=15;mob++;}
if(g_board[to]&enemy){mob++;if(!(g_board[to]&piecePawn)){to-=15;while(g_board[to]==0)to-=15;mob+=mobUnit[g_board[to]]<<2;}}
to=from-17;while(g_board[to]==0){to-=17;mob++;}
if(g_board[to]&enemy){mob++;if(!(g_board[to]&piecePawn)){to-=17;while(g_board[to]==0)to-=17;mob+=mobUnit[g_board[to]]<<2;}}
to=from+15;while(g_board[to]==0){to+=15;mob++;}
if(g_board[to]&enemy){mob++;if(!(g_board[to]&piecePawn)){to+=15;while(g_board[to]==0)to+=15;mob+=mobUnit[g_board[to]]<<2;}}
to=from+17;while(g_board[to]==0){to+=17;mob++;}
if(g_board[to]&enemy){mob++;if(!(g_board[to]&piecePawn)){to+=17;while(g_board[to]==0)to+=17;mob+=mobUnit[g_board[to]]<<2;}}
from=g_pieceList[pieceIdx++];}
result+=44*mob;mob=-4;pieceIdx=(color|4)<<4;from=g_pieceList[pieceIdx++];while(from!=0){to=from-1;while(g_board[to]==0){to--;mob++;}
if(g_board[to]&enemy)mob++;to=from+1;while(g_board[to]==0){to++;mob++;}
if(g_board[to]&enemy)mob++;to=from+16;while(g_board[to]==0){to+=16;mob++;}
if(g_board[to]&enemy)mob++;to=from-16;while(g_board[to]==0){to-=16;mob++;}
if(g_board[to]&enemy)mob++;from=g_pieceList[pieceIdx++];}
result+=25*mob;mob=-2;pieceIdx=(color|5)<<4;from=g_pieceList[pieceIdx++];while(from!=0){to=from-15;while(g_board[to]==0){to-=15;mob++;}
if(g_board[to]&enemy)mob++;to=from-17;while(g_board[to]==0){to-=17;mob++;}
if(g_board[to]&enemy)mob++;to=from+15;while(g_board[to]==0){to+=15;mob++;}
if(g_board[to]&enemy)mob++;to=from+17;while(g_board[to]==0){to+=17;mob++;}
if(g_board[to]&enemy)mob++;to=from-1;while(g_board[to]==0){to--;mob++;}
if(g_board[to]&enemy)mob++;to=from+1;while(g_board[to]==0){to++;mob++;}
if(g_board[to]&enemy)mob++;to=from+16;while(g_board[to]==0){to+=16;mob++;}
if(g_board[to]&enemy)mob++;to=from-16;while(g_board[to]==0){to-=16;mob++;}
if(g_board[to]&enemy)mob++;from=g_pieceList[pieceIdx++];}
result+=22*mob;return result;}
function Evaluate(){var curEval=g_baseEval;var evalAdjust=0;if(g_pieceList[pieceQueen<<4]==0)
evalAdjust-=pieceSquareAdj[pieceKing][g_pieceList[(colorWhite|pieceKing)<<4]];if(g_pieceList[(colorWhite|pieceQueen)<<4]==0)
evalAdjust+=pieceSquareAdj[pieceKing][flipTable[g_pieceList[pieceKing<<4]]];if(g_pieceCount[pieceBishop]>=2)
evalAdjust-=500;if(g_pieceCount[pieceBishop|colorWhite]>=2)
evalAdjust+=500;var mobility=Mobility(8)-Mobility(0);if(g_toMove==0){curEval-=mobility;curEval-=evalAdjust;}else{curEval+=mobility;curEval+=evalAdjust;}
return curEval;}
function ScoreMove(move){var moveTo=(move>>8)&0xFF;var captured=g_board[moveTo]&0x7;var piece=g_board[move&0xFF];var score;if(captured!=0){var pieceType=piece&0x7;score=(captured<<5)-pieceType;}else{score=historyTable[piece&0xF][moveTo];}
return score;}
function QSearch(alpha,beta,ply){g_qNodeCount++;var realEval=g_inCheck?(minEval+1):Evaluate();if(realEval>=beta)
return realEval;if(realEval>alpha)
alpha=realEval;var moves=new Array();var moveScores=new Array();var wasInCheck=g_inCheck;if(wasInCheck){GenerateCaptureMoves(moves,null);GenerateAllMoves(moves);for(var i=0;i<moves.length;i++){moveScores[i]=ScoreMove(moves[i]);}}else{GenerateCaptureMoves(moves,null);for(var i=0;i<moves.length;i++){var captured=g_board[(moves[i]>>8)&0xFF]&0x7;var pieceType=g_board[moves[i]&0xFF]&0x7;moveScores[i]=(captured<<5)-pieceType;}}
for(var i=0;i<moves.length;i++){var bestMove=i;for(var j=moves.length-1;j>i;j--){if(moveScores[j]>moveScores[bestMove]){bestMove=j;}}{var tmpMove=moves[i];moves[i]=moves[bestMove];moves[bestMove]=tmpMove;var tmpScore=moveScores[i];moveScores[i]=moveScores[bestMove];moveScores[bestMove]=tmpScore;}
if(!wasInCheck&&!See(moves[i])){continue;}
if(!MakeMove(moves[i])){continue;}
var value=-QSearch(-beta,-alpha,ply-1);UnmakeMove(moves[i]);if(value>realEval){if(value>=beta)
return value;if(value>alpha)
alpha=value;realEval=value;}}
return realEval;}
function StoreHash(value,flags,ply,move,depth){if(value>=maxMateBuffer)
value+=depth;else if(value<=minMateBuffer)
value-=depth;g_hashTable[g_hashKeyLow&g_hashMask]=new HashEntry(g_hashKeyHigh,value,flags,ply,move);}
function IsHashMoveValid(hashMove){var from=hashMove&0xFF;var to=(hashMove>>8)&0xFF;var ourPiece=g_board[from];var pieceType=ourPiece&0x7;if(pieceType<piecePawn||pieceType>pieceKing)return false;if(g_toMove!=(ourPiece&0x8))
return false;if(g_board[to]!=0&&(g_toMove==(g_board[to]&0x8)))
return false;if(pieceType==piecePawn){if(hashMove&moveflagEPC){return false;}
var dir=to-from;if((g_toMove==colorWhite)!=(dir<0)){return false;}
var row=to&0xF0;if(((row==0x90&&!g_toMove)||(row==0x20&&g_toMove))!=(hashMove&moveflagPromotion)){return false;}
if(dir==-16||dir==16){return g_board[to]==0;}else if(dir==-15||dir==-17||dir==15||dir==17){return g_board[to]!=0;}else if(dir==-32){if(row!=0x60)return false;if(g_board[to]!=0)return false;if(g_board[from-16]!=0)return false;}else if(dir==32){if(row!=0x50)return false;if(g_board[to]!=0)return false;if(g_board[from+16]!=0)return false;}else{return false;}
return true;}else{if(hashMove>>16)return false;return IsSquareAttackableFrom(to,from);}}
function IsRepDraw(){var stop=g_moveCount-1-g_move50;stop=stop<0?0:stop;for(var i=g_moveCount-5;i>=stop;i-=2){if(g_repMoveStack[i]==g_hashKeyLow)
return true;}
return false;}
function MovePicker(hashMove,depth,killer1,killer2){this.hashMove=hashMove;this.depth=depth;this.killer1=killer1;this.killer2=killer2;this.moves=new Array();this.losingCaptures=null;this.moveCount=0;this.atMove=-1;this.moveScores=null;this.stage=0;this.nextMove=function(){if(++this.atMove==this.moveCount){this.stage++;if(this.stage==1){if(this.hashMove!=null&&IsHashMoveValid(hashMove)){this.moves[0]=hashMove;this.moveCount=1;}
if(this.moveCount!=1){this.hashMove=null;this.stage++;}}
if(this.stage==2){GenerateCaptureMoves(this.moves,null);this.moveCount=this.moves.length;this.moveScores=new Array(this.moveCount);for(var i=this.atMove;i<this.moveCount;i++){var captured=g_board[(this.moves[i]>>8)&0xFF]&0x7;var pieceType=g_board[this.moves[i]&0xFF]&0x7;this.moveScores[i]=(captured<<5)-pieceType;}
if(this.atMove==this.moveCount)this.stage++;}
if(this.stage==3){if(IsHashMoveValid(this.killer1)&&this.killer1!=this.hashMove){this.moves[this.moves.length]=this.killer1;this.moveCount=this.moves.length;}else{this.killer1=0;this.stage++;}}
if(this.stage==4){if(IsHashMoveValid(this.killer2)&&this.killer2!=this.hashMove){this.moves[this.moves.length]=this.killer2;this.moveCount=this.moves.length;}else{this.killer2=0;this.stage++;}}
if(this.stage==5){GenerateAllMoves(this.moves);this.moveCount=this.moves.length;for(var i=this.atMove;i<this.moveCount;i++)this.moveScores[i]=ScoreMove(this.moves[i]);if(this.atMove==this.moveCount)this.stage++;}
if(this.stage==6){if(this.losingCaptures!=null){for(var i=0;i<this.losingCaptures.length;i++){this.moves[this.moves.length]=this.losingCaptures[i];}
for(var i=this.atMove;i<this.moveCount;i++)this.moveScores[i]=ScoreMove(this.moves[i]);this.moveCount=this.moves.length;}
if(this.atMove==this.moveCount)this.stage++;}
if(this.stage==7)
return 0;}
var bestMove=this.atMove;for(var j=this.atMove+1;j<this.moveCount;j++){if(this.moveScores[j]>this.moveScores[bestMove]){bestMove=j;}}
if(bestMove!=this.atMove){var tmpMove=this.moves[this.atMove];this.moves[this.atMove]=this.moves[bestMove];this.moves[bestMove]=tmpMove;var tmpScore=this.moveScores[this.atMove];this.moveScores[this.atMove]=this.moveScores[bestMove];this.moveScores[bestMove]=tmpScore;}
var candidateMove=this.moves[this.atMove];if((this.stage>1&&candidateMove==this.hashMove)||(this.stage>3&&candidateMove==this.killer1)||(this.stage>4&&candidateMove==this.killer2)){return this.nextMove();}
if(this.stage==2&&!See(candidateMove)){if(this.losingCaptures==null){this.losingCaptures=new Array();}
this.losingCaptures[this.losingCaptures.length]=candidateMove;return this.nextMove();}
return this.moves[this.atMove];}}
function AllCutNode(ply,depth,beta,allowNull){if(ply<=0){return QSearch(beta-1,beta,0);}
if((g_nodeCount&127)==127){if((new Date()).getTime()-g_startTime>g_timeout){g_searchValid=false;return beta-1;}}
g_nodeCount++;if(IsRepDraw())
return 0;if(minEval+depth>=beta)
return beta;if(maxEval-(depth+1)<beta)
return beta-1;var hashMove=null;var hashNode=g_hashTable[g_hashKeyLow&g_hashMask];if(hashNode!=null&&hashNode.lock==g_hashKeyHigh){hashMove=hashNode.bestMove;if(hashNode.hashDepth>=ply){var hashValue=hashNode.value;if(hashValue>=maxMateBuffer)
hashValue-=depth;else if(hashValue<=minMateBuffer)
hashValue+=depth;if(hashNode.flags==hashflagExact)
return hashValue;if(hashNode.flags==hashflagAlpha&&hashValue<beta)
return hashValue;if(hashNode.flags==hashflagBeta&&hashValue>=beta)
return hashValue;}}
if(!g_inCheck&&allowNull&&beta>minMateBuffer&&beta<maxMateBuffer){if(hashMove==null&&ply<4){var razorMargin=2500+200*ply;if(g_baseEval<beta-razorMargin){var razorBeta=beta-razorMargin;var v=QSearch(razorBeta-1,razorBeta,0);if(v<razorBeta)
return v;}}
if(ply>1&&g_baseEval>=beta-(ply>=4?2500:0)&&(g_pieceCount[pieceBishop|g_toMove]!=0||g_pieceCount[pieceKnight|g_toMove]!=0||g_pieceCount[pieceRook|g_toMove]!=0||g_pieceCount[pieceQueen|g_toMove]!=0)){var r=3+(ply>=5?1:ply/4);if(g_baseEval-beta>1500)r++;g_toMove=8-g_toMove;g_baseEval=-g_baseEval;g_hashKeyLow^=g_zobristBlackLow;g_hashKeyHigh^=g_zobristBlackHigh;var value=-AllCutNode(ply-r,depth+1,-(beta-1),false);g_hashKeyLow^=g_zobristBlackLow;g_hashKeyHigh^=g_zobristBlackHigh;g_toMove=8-g_toMove;g_baseEval=-g_baseEval;if(value>=beta)
return beta;}}
var moveMade=false;var realEval=minEval-1;var inCheck=g_inCheck;var movePicker=new MovePicker(hashMove,depth,g_killers[depth][0],g_killers[depth][1]);for(;;){var currentMove=movePicker.nextMove();if(currentMove==0){break;}
var plyToSearch=ply-1;if(!MakeMove(currentMove)){continue;}
var value;var doFullSearch=true;if(g_inCheck){plyToSearch++;}else{var reduced=plyToSearch-(movePicker.atMove>14?2:1);if(movePicker.stage==5&&movePicker.atMove>5&&ply>=3){value=-AllCutNode(reduced,depth+1,-(beta-1),true);doFullSearch=(value>=beta);}}
if(doFullSearch){value=-AllCutNode(plyToSearch,depth+1,-(beta-1),true);}
moveMade=true;UnmakeMove(currentMove);if(!g_searchValid){return beta-1;}
if(value>realEval){if(value>=beta){var histTo=(currentMove>>8)&0xFF;if(g_board[histTo]==0){var histPiece=g_board[currentMove&0xFF]&0xF;historyTable[histPiece][histTo]+=ply*ply;if(historyTable[histPiece][histTo]>32767){historyTable[histPiece][histTo]>>=1;}
if(g_killers[depth][0]!=currentMove){g_killers[depth][1]=g_killers[depth][0];g_killers[depth][0]=currentMove;}}
StoreHash(value,hashflagBeta,ply,currentMove,depth);return value;}
realEval=value;hashMove=currentMove;}}
if(!moveMade){if(g_inCheck)
return minEval+depth;else
return 0;}
StoreHash(realEval,hashflagAlpha,ply,hashMove,depth);return realEval;}
function AlphaBeta(ply,depth,alpha,beta){if(ply<=0){return QSearch(alpha,beta,0);}
g_nodeCount++;if(depth>0&&IsRepDraw())
return 0;var oldAlpha=alpha;alpha=alpha<minEval+depth?alpha:minEval+depth;beta=beta>maxEval-(depth+1)?beta:maxEval-(depth+1);if(alpha>=beta)
return alpha;var hashMove=null;var hashFlag=hashflagAlpha;var hashNode=g_hashTable[g_hashKeyLow&g_hashMask];if(hashNode!=null&&hashNode.lock==g_hashKeyHigh){hashMove=hashNode.bestMove;}
var inCheck=g_inCheck;var moveMade=false;var realEval=minEval;var movePicker=new MovePicker(hashMove,depth,g_killers[depth][0],g_killers[depth][1]);for(;;){var currentMove=movePicker.nextMove();if(currentMove==0){break;}
var plyToSearch=ply-1;if(!MakeMove(currentMove)){continue;}
if(g_inCheck){plyToSearch++;}
var value;if(moveMade){value=-AllCutNode(plyToSearch,depth+1,-alpha,true);if(value>alpha){value=-AlphaBeta(plyToSearch,depth+1,-beta,-alpha);}}else{value=-AlphaBeta(plyToSearch,depth+1,-beta,-alpha);}
moveMade=true;UnmakeMove(currentMove);if(!g_searchValid){return alpha;}
if(value>realEval){if(value>=beta){var histTo=(currentMove>>8)&0xFF;if(g_board[histTo]==0){var histPiece=g_board[currentMove&0xFF]&0xF;historyTable[histPiece][histTo]+=ply*ply;if(historyTable[histPiece][histTo]>32767){historyTable[histPiece][histTo]>>=1;}
if(g_killers[depth][0]!=currentMove){g_killers[depth][1]=g_killers[depth][0];g_killers[depth][0]=currentMove;}}
StoreHash(value,hashflagBeta,ply,currentMove,depth);return value;}
if(value>oldAlpha){hashFlag=hashflagExact;alpha=value;}
realEval=value;hashMove=currentMove;}}
if(!moveMade){if(inCheck)
return minEval+depth;else
return 0;}
StoreHash(realEval,hashFlag,ply,hashMove,depth);return realEval;}
var colorBlack=0x10;var colorWhite=0x08;var pieceEmpty=0x00;var piecePawn=0x01;var pieceKnight=0x02;var pieceBishop=0x03;var pieceRook=0x04;var pieceQueen=0x05;var pieceKing=0x06;var g_vectorDelta=new Array(256);var g_bishopDeltas=[-15,-17,15,17];var g_knightDeltas=[31,33,14,-14,-31,-33,18,-18];var g_rookDeltas=[-1,+1,-16,+16];var g_queenDeltas=[-1,+1,-15,+15,-17,+17,-16,+16];var g_castleRightsMask=[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,7,15,15,15,3,15,15,11,0,0,0,0,0,0,0,0,15,15,15,15,15,15,15,15,0,0,0,0,0,0,0,0,15,15,15,15,15,15,15,15,0,0,0,0,0,0,0,0,15,15,15,15,15,15,15,15,0,0,0,0,0,0,0,0,15,15,15,15,15,15,15,15,0,0,0,0,0,0,0,0,15,15,15,15,15,15,15,15,0,0,0,0,0,0,0,0,15,15,15,15,15,15,15,15,0,0,0,0,0,0,0,0,13,15,15,15,12,15,15,14,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0];var moveflagEPC=0x2<<16;var moveflagCastleKing=0x4<<16;var moveflagCastleQueen=0x8<<16;var moveflagPromotion=0x10<<16;var moveflagPromoteKnight=0x20<<16;var moveflagPromoteQueen=0x40<<16;var moveflagPromoteBishop=0x80<<16;function MT(){var N=624;var M=397;var MAG01=[0x0,0x9908b0df];this.mt=new Array(N);this.mti=N+1;this.setSeed=function(){var a=arguments;switch(a.length){case 1:if(a[0].constructor===Number){this.mt[0]=a[0];for(var i=1;i<N;++i){var s=this.mt[i-1]^(this.mt[i-1]>>>30);this.mt[i]=((1812433253*((s&0xffff0000)>>>16))<<16)+1812433253*(s&0x0000ffff)+i;}
this.mti=N;return;}
this.setSeed(19650218);var l=a[0].length;var i=1;var j=0;for(var k=N>l?N:l;k!=0;--k){var s=this.mt[i-1]^(this.mt[i-1]>>>30)
this.mt[i]=(this.mt[i]^(((1664525*((s&0xffff0000)>>>16))<<16)+1664525*(s&0x0000ffff)))+a[0][j]+j;if(++i>=N){this.mt[0]=this.mt[N-1];i=1;}
if(++j>=l){j=0;}}
for(var k=N-1;k!=0;--k){var s=this.mt[i-1]^(this.mt[i-1]>>>30);this.mt[i]=(this.mt[i]^(((1566083941*((s&0xffff0000)>>>16))<<16)+1566083941*(s&0x0000ffff)))-i;if(++i>=N){this.mt[0]=this.mt[N-1];i=1;}}
this.mt[0]=0x80000000;return;default:var seeds=new Array();for(var i=0;i<a.length;++i){seeds.push(a[i]);}
this.setSeed(seeds);return;}}
this.setSeed(0x1BADF00D);this.next=function(bits){if(this.mti>=N){var x=0;for(var k=0;k<N-M;++k){x=(this.mt[k]&0x80000000)|(this.mt[k+1]&0x7fffffff);this.mt[k]=this.mt[k+M]^(x>>>1)^MAG01[x&0x1];}
for(var k=N-M;k<N-1;++k){x=(this.mt[k]&0x80000000)|(this.mt[k+1]&0x7fffffff);this.mt[k]=this.mt[k+(M-N)]^(x>>>1)^MAG01[x&0x1];}
x=(this.mt[N-1]&0x80000000)|(this.mt[0]&0x7fffffff);this.mt[N-1]=this.mt[M-1]^(x>>>1)^MAG01[x&0x1];this.mti=0;}
var y=this.mt[this.mti++];y^=y>>>11;y^=(y<<7)&0x9d2c5680;y^=(y<<15)&0xefc60000;y^=y>>>18;return(y>>>(32-bits))&0xFFFFFFFF;}}
var g_board=new Array(256);var g_toMove;var g_castleRights;var g_enPassentSquare;var g_baseEval;var g_hashKeyLow,g_hashKeyHigh;var g_inCheck;var g_moveCount=0;var g_moveUndoStack=new Array();var g_move50=0;var g_repMoveStack=new Array();var g_hashSize=1<<22;var g_hashMask=g_hashSize-1;var g_hashTable;var g_killers;var historyTable=new Array(32);var g_zobristLow;var g_zobristHigh;var g_zobristBlackLow;var g_zobristBlackHigh;var g_mobUnit;var hashflagAlpha=1;var hashflagBeta=2;var hashflagExact=3;function HashEntry(lock,value,flags,hashDepth,bestMove,globalPly){this.lock=lock;this.value=value;this.flags=flags;this.hashDepth=hashDepth;this.bestMove=bestMove;}
function MakeSquare(row,column){return((row+2)<<4)|(column+4);}
function MakeTable(table){var result=new Array(256);for(var i=0;i<256;i++){result[i]=0;}
for(var row=0;row<8;row++){for(var col=0;col<8;col++){result[MakeSquare(row,col)]=table[row*8+col];}}
return result;}
function ResetGame(){g_killers=new Array(128);for(var i=0;i<128;i++){g_killers[i]=[0,0];}
g_hashTable=new Array(g_hashSize);for(var i=0;i<32;i++){historyTable[i]=new Array(256);for(var j=0;j<256;j++)
historyTable[i][j]=0;}
var mt=new MT(0x1badf00d);g_zobristLow=new Array(256);g_zobristHigh=new Array(256);for(var i=0;i<256;i++){g_zobristLow[i]=new Array(16);g_zobristHigh[i]=new Array(16);for(var j=0;j<16;j++){g_zobristLow[i][j]=mt.next(32);g_zobristHigh[i][j]=mt.next(32);}}
g_zobristBlackLow=mt.next(32);g_zobristBlackHigh=mt.next(32);for(var row=0;row<8;row++){for(var col=0;col<8;col++){var square=MakeSquare(row,col);flipTable[square]=MakeSquare(7-row,col);}}
pieceSquareAdj[piecePawn]=MakeTable(pawnAdj);pieceSquareAdj[pieceKnight]=MakeTable(knightAdj);pieceSquareAdj[pieceBishop]=MakeTable(bishopAdj);pieceSquareAdj[pieceRook]=MakeTable(rookAdj);pieceSquareAdj[pieceQueen]=MakeTable(emptyAdj);pieceSquareAdj[pieceKing]=MakeTable(kingAdj);var pieceDeltas=[[],[],g_knightDeltas,g_bishopDeltas,g_rookDeltas,g_queenDeltas,g_queenDeltas];for(var i=0;i<256;i++){g_vectorDelta[i]=new Object();g_vectorDelta[i].delta=0;g_vectorDelta[i].pieceMask=new Array(2);g_vectorDelta[i].pieceMask[0]=0;g_vectorDelta[i].pieceMask[1]=0;}
for(var row=0;row<0x80;row+=0x10)
for(var col=0;col<0x8;col++){var square=row|col;var index=square-(square-17)+128;g_vectorDelta[index].pieceMask[colorWhite>>3]|=(1<<piecePawn);index=square-(square-15)+128;g_vectorDelta[index].pieceMask[colorWhite>>3]|=(1<<piecePawn);index=square-(square+17)+128;g_vectorDelta[index].pieceMask[0]|=(1<<piecePawn);index=square-(square+15)+128;g_vectorDelta[index].pieceMask[0]|=(1<<piecePawn);for(var i=pieceKnight;i<=pieceKing;i++){for(var dir=0;dir<pieceDeltas[i].length;dir++){var target=square+pieceDeltas[i][dir];while(!(target&0x88)){index=square-target+128;g_vectorDelta[index].pieceMask[colorWhite>>3]|=(1<<i);g_vectorDelta[index].pieceMask[0]|=(1<<i);var flip=-1;if(square<target)
flip=1;if((square&0xF0)==(target&0xF0)){g_vectorDelta[index].delta=flip*1;}else if((square&0x0F)==(target&0x0F)){g_vectorDelta[index].delta=flip*16;}else if((square%15)==(target%15)){g_vectorDelta[index].delta=flip*15;}else if((square%17)==(target%17)){g_vectorDelta[index].delta=flip*17;}
if(i==pieceKnight){g_vectorDelta[index].delta=pieceDeltas[i][dir];break;}
if(i==pieceKing)
break;target+=pieceDeltas[i][dir];}}}}
InitializeEval();InitializeFromFen("rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1");}
function InitializeEval(){g_mobUnit=new Array(2);for(var i=0;i<2;i++){g_mobUnit[i]=new Array();var enemy=i==0?0x10:8;var friend=i==0?8:0x10;g_mobUnit[i][0]=1;g_mobUnit[i][0x80]=0;g_mobUnit[i][enemy|piecePawn]=1;g_mobUnit[i][enemy|pieceBishop]=2;g_mobUnit[i][enemy|pieceKnight]=2;g_mobUnit[i][enemy|pieceRook]=4;g_mobUnit[i][enemy|pieceQueen]=6;g_mobUnit[i][enemy|pieceKing]=6;g_mobUnit[i][friend|piecePawn]=0;g_mobUnit[i][friend|pieceBishop]=0;g_mobUnit[i][friend|pieceKnight]=0;g_mobUnit[i][friend|pieceRook]=0;g_mobUnit[i][friend|pieceQueen]=0;g_mobUnit[i][friend|pieceKing]=0;}}
function SetHash(){var result=new Object();result.hashKeyLow=0;result.hashKeyHigh=0;for(var i=0;i<256;i++){var piece=g_board[i];if(piece&0x18){result.hashKeyLow^=g_zobristLow[i][piece&0xF]
result.hashKeyHigh^=g_zobristHigh[i][piece&0xF]}}
if(!g_toMove){result.hashKeyLow^=g_zobristBlackLow;result.hashKeyHigh^=g_zobristBlackHigh;}
return result;}
function InitializeFromFen(fen){var chunks=fen.split(' ');for(var i=0;i<256;i++)
g_board[i]=0x80;var row=0;var col=0;var pieces=chunks[0];for(var i=0;i<pieces.length;i++){var c=pieces.charAt(i);if(c=='../index.html'){row++;col=0;}else{if(c>='0'&&c<='9'){for(var j=0;j<parseInt(c);j++){g_board[MakeSquare(row,col)]=0;col++;}}else{var isBlack=c>='a'&&c<='z';var piece=isBlack?colorBlack:colorWhite;if(!isBlack)
c=pieces.toLowerCase().charAt(i);switch(c){case 'p':piece|=piecePawn;break;case 'b':piece|=pieceBishop;break;case 'n':piece|=pieceKnight;break;case 'r':piece|=pieceRook;break;case 'q':piece|=pieceQueen;break;case 'k':piece|=pieceKing;break;}
g_board[MakeSquare(row,col)]=piece;col++;}}}
InitializePieceList();g_toMove=chunks[1].charAt(0)=='w'?colorWhite:0;var them=8-g_toMove;g_castleRights=0;if(chunks[2].indexOf('K')!=-1){if(g_board[MakeSquare(7,4)]!=(pieceKing|colorWhite)||g_board[MakeSquare(7,7)]!=(pieceRook|colorWhite)){return 'Invalid FEN: White kingside castling not allowed';}
g_castleRights|=1;}
if(chunks[2].indexOf('Q')!=-1){if(g_board[MakeSquare(7,4)]!=(pieceKing|colorWhite)||g_board[MakeSquare(7,0)]!=(pieceRook|colorWhite)){return 'Invalid FEN: White queenside castling not allowed';}
g_castleRights|=2;}
if(chunks[2].indexOf('k')!=-1){if(g_board[MakeSquare(0,4)]!=(pieceKing|colorBlack)||g_board[MakeSquare(0,7)]!=(pieceRook|colorBlack)){return 'Invalid FEN: Black kingside castling not allowed';}
g_castleRights|=4;}
if(chunks[2].indexOf('q')!=-1){if(g_board[MakeSquare(0,4)]!=(pieceKing|colorBlack)||g_board[MakeSquare(0,0)]!=(pieceRook|colorBlack)){return 'Invalid FEN: Black queenside castling not allowed';}
g_castleRights|=8;}
g_enPassentSquare=-1;if(chunks[3].indexOf('-')==-1){var col=chunks[3].charAt(0).charCodeAt()-'a'.charCodeAt();var row=8-(chunks[3].charAt(1).charCodeAt()-'0'.charCodeAt());g_enPassentSquare=MakeSquare(row,col);}
var hashResult=SetHash();g_hashKeyLow=hashResult.hashKeyLow;g_hashKeyHigh=hashResult.hashKeyHigh;g_baseEval=0;for(var i=0;i<256;i++){if(g_board[i]&colorWhite){g_baseEval+=pieceSquareAdj[g_board[i]&0x7][i];g_baseEval+=materialTable[g_board[i]&0x7];}else if(g_board[i]&colorBlack){g_baseEval-=pieceSquareAdj[g_board[i]&0x7][flipTable[i]];g_baseEval-=materialTable[g_board[i]&0x7];}}
if(!g_toMove)g_baseEval=-g_baseEval;g_move50=0;g_inCheck=IsSquareAttackable(g_pieceList[(g_toMove|pieceKing)<<4],them);if(IsSquareAttackable(g_pieceList[(them|pieceKing)<<4],g_toMove)){return 'Invalid FEN: Can capture king';}
if(GenerateValidMoves().length==0){return g_inCheck?'Checkmate':'Stalemate';}
return '';}
var g_pieceIndex=new Array(256);var g_pieceList=new Array(2*8*16);var g_pieceCount=new Array(2*8);function InitializePieceList(){for(var i=0;i<16;i++){g_pieceCount[i]=0;for(var j=0;j<16;j++){g_pieceList[(i<<4)|j]=0;}}
for(var i=0;i<256;i++){g_pieceIndex[i]=0;if(g_board[i]&(colorWhite|colorBlack)){var piece=g_board[i]&0xF;g_pieceList[(piece<<4)|g_pieceCount[piece]]=i;g_pieceIndex[i]=g_pieceCount[piece];g_pieceCount[piece]++;}}}
function MakeMove(move){var me=g_toMove>>3;var otherColor=8-g_toMove;var flags=move&0xFF0000;var to=(move>>8)&0xFF;var from=move&0xFF;var captured=g_board[to];var piece=g_board[from];var epcEnd=to;if(flags&moveflagEPC){epcEnd=me?(to+0x10):(to-0x10);captured=g_board[epcEnd];g_board[epcEnd]=pieceEmpty;}
g_moveUndoStack[g_moveCount]=new UndoHistory(g_enPassentSquare,g_castleRights,g_inCheck,g_baseEval,g_hashKeyLow,g_hashKeyHigh,g_move50,captured);g_moveCount++;g_enPassentSquare=-1;if(flags){if(flags&moveflagCastleKing){if(IsSquareAttackable(from+1,otherColor)||IsSquareAttackable(from+2,otherColor)){g_moveCount--;return false;}
var rook=g_board[to+1];g_hashKeyLow^=g_zobristLow[to+1][rook&0xF];g_hashKeyHigh^=g_zobristHigh[to+1][rook&0xF];g_hashKeyLow^=g_zobristLow[to-1][rook&0xF];g_hashKeyHigh^=g_zobristHigh[to-1][rook&0xF];g_board[to-1]=rook;g_board[to+1]=pieceEmpty;g_baseEval-=pieceSquareAdj[rook&0x7][me==0?flipTable[to+1]:(to+1)];g_baseEval+=pieceSquareAdj[rook&0x7][me==0?flipTable[to-1]:(to-1)];var rookIndex=g_pieceIndex[to+1];g_pieceIndex[to-1]=rookIndex;g_pieceList[((rook&0xF)<<4)|rookIndex]=to-1;}else if(flags&moveflagCastleQueen){if(IsSquareAttackable(from-1,otherColor)||IsSquareAttackable(from-2,otherColor)){g_moveCount--;return false;}
var rook=g_board[to-2];g_hashKeyLow^=g_zobristLow[to-2][rook&0xF];g_hashKeyHigh^=g_zobristHigh[to-2][rook&0xF];g_hashKeyLow^=g_zobristLow[to+1][rook&0xF];g_hashKeyHigh^=g_zobristHigh[to+1][rook&0xF];g_board[to+1]=rook;g_board[to-2]=pieceEmpty;g_baseEval-=pieceSquareAdj[rook&0x7][me==0?flipTable[to-2]:(to-2)];g_baseEval+=pieceSquareAdj[rook&0x7][me==0?flipTable[to+1]:(to+1)];var rookIndex=g_pieceIndex[to-2];g_pieceIndex[to+1]=rookIndex;g_pieceList[((rook&0xF)<<4)|rookIndex]=to+1;}}
if(captured){var capturedType=captured&0xF;g_pieceCount[capturedType]--;var lastPieceSquare=g_pieceList[(capturedType<<4)|g_pieceCount[capturedType]];g_pieceIndex[lastPieceSquare]=g_pieceIndex[epcEnd];g_pieceList[(capturedType<<4)|g_pieceIndex[lastPieceSquare]]=lastPieceSquare;g_pieceList[(capturedType<<4)|g_pieceCount[capturedType]]=0;g_baseEval+=materialTable[captured&0x7];g_baseEval+=pieceSquareAdj[captured&0x7][me?flipTable[epcEnd]:epcEnd];g_hashKeyLow^=g_zobristLow[epcEnd][capturedType];g_hashKeyHigh^=g_zobristHigh[epcEnd][capturedType];g_move50=0;}else if((piece&0x7)==piecePawn){var diff=to-from;if(diff<0)diff=-diff;if(diff>16){g_enPassentSquare=me?(to+0x10):(to-0x10);}
g_move50=0;}
g_hashKeyLow^=g_zobristLow[from][piece&0xF];g_hashKeyHigh^=g_zobristHigh[from][piece&0xF];g_hashKeyLow^=g_zobristLow[to][piece&0xF];g_hashKeyHigh^=g_zobristHigh[to][piece&0xF];g_hashKeyLow^=g_zobristBlackLow;g_hashKeyHigh^=g_zobristBlackHigh;g_castleRights&=g_castleRightsMask[from]&g_castleRightsMask[to];g_baseEval-=pieceSquareAdj[piece&0x7][me==0?flipTable[from]:from];g_pieceIndex[to]=g_pieceIndex[from];g_pieceList[((piece&0xF)<<4)|g_pieceIndex[to]]=to;if(flags&moveflagPromotion){var newPiece=piece&(~0x7);if(flags&moveflagPromoteKnight)
newPiece|=pieceKnight;else if(flags&moveflagPromoteQueen)
newPiece|=pieceQueen;else if(flags&moveflagPromoteBishop)
newPiece|=pieceBishop;else
newPiece|=pieceRook;g_hashKeyLow^=g_zobristLow[to][piece&0xF];g_hashKeyHigh^=g_zobristHigh[to][piece&0xF];g_board[to]=newPiece;g_hashKeyLow^=g_zobristLow[to][newPiece&0xF];g_hashKeyHigh^=g_zobristHigh[to][newPiece&0xF];g_baseEval+=pieceSquareAdj[newPiece&0x7][me==0?flipTable[to]:to];g_baseEval-=materialTable[piecePawn];g_baseEval+=materialTable[newPiece&0x7];var pawnType=piece&0xF;var promoteType=newPiece&0xF;g_pieceCount[pawnType]--;var lastPawnSquare=g_pieceList[(pawnType<<4)|g_pieceCount[pawnType]];g_pieceIndex[lastPawnSquare]=g_pieceIndex[to];g_pieceList[(pawnType<<4)|g_pieceIndex[lastPawnSquare]]=lastPawnSquare;g_pieceList[(pawnType<<4)|g_pieceCount[pawnType]]=0;g_pieceIndex[to]=g_pieceCount[promoteType];g_pieceList[(promoteType<<4)|g_pieceIndex[to]]=to;g_pieceCount[promoteType]++;}else{g_board[to]=g_board[from];g_baseEval+=pieceSquareAdj[piece&0x7][me==0?flipTable[to]:to];}
g_board[from]=pieceEmpty;g_toMove=otherColor;g_baseEval=-g_baseEval;if((piece&0x7)==pieceKing||g_inCheck){if(IsSquareAttackable(g_pieceList[(pieceKing|(8-g_toMove))<<4],otherColor)){UnmakeMove(move);return false;}}else{var kingPos=g_pieceList[(pieceKing|(8-g_toMove))<<4];if(ExposesCheck(from,kingPos)){UnmakeMove(move);return false;}
if(epcEnd!=to){if(ExposesCheck(epcEnd,kingPos)){UnmakeMove(move);return false;}}}
g_inCheck=false;if(flags<=moveflagEPC){var theirKingPos=g_pieceList[(pieceKing|g_toMove)<<4];g_inCheck=IsSquareAttackableFrom(theirKingPos,to);if(!g_inCheck){g_inCheck=ExposesCheck(from,theirKingPos);if(!g_inCheck){if(epcEnd!=to){g_inCheck=ExposesCheck(epcEnd,theirKingPos);}}}}else{g_inCheck=IsSquareAttackable(g_pieceList[(pieceKing|g_toMove)<<4],8-g_toMove);}
g_repMoveStack[g_moveCount-1]=g_hashKeyLow;g_move50++;return true;}
function UnmakeMove(move){g_toMove=8-g_toMove;g_baseEval=-g_baseEval;g_moveCount--;g_enPassentSquare=g_moveUndoStack[g_moveCount].ep;g_castleRights=g_moveUndoStack[g_moveCount].castleRights;g_inCheck=g_moveUndoStack[g_moveCount].inCheck;g_baseEval=g_moveUndoStack[g_moveCount].baseEval;g_hashKeyLow=g_moveUndoStack[g_moveCount].hashKeyLow;g_hashKeyHigh=g_moveUndoStack[g_moveCount].hashKeyHigh;g_move50=g_moveUndoStack[g_moveCount].move50;var otherColor=8-g_toMove;var me=g_toMove>>3;var them=otherColor>>3;var flags=move&0xFF0000;var captured=g_moveUndoStack[g_moveCount].captured;var to=(move>>8)&0xFF;var from=move&0xFF;var piece=g_board[to];if(flags){if(flags&moveflagCastleKing){var rook=g_board[to-1];g_board[to+1]=rook;g_board[to-1]=pieceEmpty;var rookIndex=g_pieceIndex[to-1];g_pieceIndex[to+1]=rookIndex;g_pieceList[((rook&0xF)<<4)|rookIndex]=to+1;}else if(flags&moveflagCastleQueen){var rook=g_board[to+1];g_board[to-2]=rook;g_board[to+1]=pieceEmpty;var rookIndex=g_pieceIndex[to+1];g_pieceIndex[to-2]=rookIndex;g_pieceList[((rook&0xF)<<4)|rookIndex]=to-2;}}
if(flags&moveflagPromotion){piece=(g_board[to]&(~0x7))|piecePawn;g_board[from]=piece;var pawnType=g_board[from]&0xF;var promoteType=g_board[to]&0xF;g_pieceCount[promoteType]--;var lastPromoteSquare=g_pieceList[(promoteType<<4)|g_pieceCount[promoteType]];g_pieceIndex[lastPromoteSquare]=g_pieceIndex[to];g_pieceList[(promoteType<<4)|g_pieceIndex[lastPromoteSquare]]=lastPromoteSquare;g_pieceList[(promoteType<<4)|g_pieceCount[promoteType]]=0;g_pieceIndex[to]=g_pieceCount[pawnType];g_pieceList[(pawnType<<4)|g_pieceIndex[to]]=to;g_pieceCount[pawnType]++;}else{g_board[from]=g_board[to];}
var epcEnd=to;if(flags&moveflagEPC){if(g_toMove==colorWhite)
epcEnd=to+0x10;else
epcEnd=to-0x10;g_board[to]=pieceEmpty;}
g_board[epcEnd]=captured;g_pieceIndex[from]=g_pieceIndex[to];g_pieceList[((piece&0xF)<<4)|g_pieceIndex[from]]=from;if(captured){var captureType=captured&0xF;g_pieceIndex[epcEnd]=g_pieceCount[captureType];g_pieceList[(captureType<<4)|g_pieceCount[captureType]]=epcEnd;g_pieceCount[captureType]++;}}
function ExposesCheck(from,kingPos){var index=kingPos-from+128;if((g_vectorDelta[index].pieceMask[0]&(1<<(pieceQueen)))!=0){var delta=g_vectorDelta[index].delta;var pos=kingPos+delta;while(g_board[pos]==0)pos+=delta;var piece=g_board[pos];if(((piece&(g_board[kingPos]^0x18))&0x18)==0)
return false;var backwardIndex=pos-kingPos+128;return(g_vectorDelta[backwardIndex].pieceMask[(piece>>3)&1]&(1<<(piece&0x7)))!=0;}
return false;}
function IsSquareOnPieceLine(target,from){var index=from-target+128;var piece=g_board[from];return(g_vectorDelta[index].pieceMask[(piece>>3)&1]&(1<<(piece&0x7)))?true:false;}
function IsSquareAttackableFrom(target,from){var index=from-target+128;var piece=g_board[from];if(g_vectorDelta[index].pieceMask[(piece>>3)&1]&(1<<(piece&0x7))){var inc=g_vectorDelta[index].delta;do{from+=inc;if(from==target)
return true;}while(g_board[from]==0);}
return false;}
function IsSquareAttackable(target,color){var inc=color?-16:16;var pawn=(color?colorWhite:colorBlack)|1;if(g_board[target-(inc-1)]==pawn)
return true;if(g_board[target-(inc+1)]==pawn)
return true;for(var i=2;i<=6;i++){var index=(color|i)<<4;var square=g_pieceList[index];while(square!=0){if(IsSquareAttackableFrom(target,square))
return true;square=g_pieceList[++index];}}
return false;}
function GenerateMove(from,to){return from|(to<<8);}
function GenerateMove(from,to,flags){return from|(to<<8)|flags;}
function GenerateValidMoves(){var moveList=new Array();var allMoves=new Array();GenerateCaptureMoves(allMoves,null);GenerateAllMoves(allMoves);for(var i=allMoves.length-1;i>=0;i--){if(MakeMove(allMoves[i])){moveList[moveList.length]=allMoves[i];UnmakeMove(allMoves[i]);}}
return moveList;}
function GenerateAllMoves(moveStack){var from,to,piece,pieceIdx;pieceIdx=(g_toMove|1)<<4;from=g_pieceList[pieceIdx++];while(from!=0){GeneratePawnMoves(moveStack,from);from=g_pieceList[pieceIdx++];}
pieceIdx=(g_toMove|2)<<4;from=g_pieceList[pieceIdx++];while(from!=0){to=from+31;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);to=from+33;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);to=from+14;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);to=from-14;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);to=from-31;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);to=from-33;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);to=from+18;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);to=from-18;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);from=g_pieceList[pieceIdx++];}
pieceIdx=(g_toMove|3)<<4;from=g_pieceList[pieceIdx++];while(from!=0){to=from-15;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to-=15;}
to=from-17;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to-=17;}
to=from+15;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to+=15;}
to=from+17;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to+=17;}
from=g_pieceList[pieceIdx++];}
pieceIdx=(g_toMove|4)<<4;from=g_pieceList[pieceIdx++];while(from!=0){to=from-1;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to--;}
to=from+1;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to++;}
to=from+16;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to+=16;}
to=from-16;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to-=16;}
from=g_pieceList[pieceIdx++];}
pieceIdx=(g_toMove|5)<<4;from=g_pieceList[pieceIdx++];while(from!=0){to=from-15;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to-=15;}
to=from-17;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to-=17;}
to=from+15;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to+=15;}
to=from+17;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to+=17;}
to=from-1;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to--;}
to=from+1;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to++;}
to=from+16;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to+=16;}
to=from-16;while(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);to-=16;}
from=g_pieceList[pieceIdx++];}
{pieceIdx=(g_toMove|6)<<4;from=g_pieceList[pieceIdx];to=from-15;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);to=from-17;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);to=from+15;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);to=from+17;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);to=from-1;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);to=from+1;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);to=from-16;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);to=from+16;if(g_board[to]==0)moveStack[moveStack.length]=GenerateMove(from,to);if(!g_inCheck){var castleRights=g_castleRights;if(!g_toMove)
castleRights>>=2;if(castleRights&1){if(g_board[from+1]==pieceEmpty&&g_board[from+2]==pieceEmpty){moveStack[moveStack.length]=GenerateMove(from,from+0x02,moveflagCastleKing);}}
if(castleRights&2){if(g_board[from-1]==pieceEmpty&&g_board[from-2]==pieceEmpty&&g_board[from-3]==pieceEmpty){moveStack[moveStack.length]=GenerateMove(from,from-0x02,moveflagCastleQueen);}}}}}
function GenerateCaptureMoves(moveStack,moveScores){var from,to,piece,pieceIdx;var inc=(g_toMove==8)?-16:16;var enemy=g_toMove==8?0x10:0x8;pieceIdx=(g_toMove|1)<<4;from=g_pieceList[pieceIdx++];while(from!=0){to=from+inc-1;if(g_board[to]&enemy){MovePawnTo(moveStack,from,to);}
to=from+inc+1;if(g_board[to]&enemy){MovePawnTo(moveStack,from,to);}
from=g_pieceList[pieceIdx++];}
if(g_enPassentSquare!=-1){var inc=(g_toMove==colorWhite)?-16:16;var pawn=g_toMove|piecePawn;var from=g_enPassentSquare-(inc+1);if((g_board[from]&0xF)==pawn){moveStack[moveStack.length]=GenerateMove(from,g_enPassentSquare,moveflagEPC);}
from=g_enPassentSquare-(inc-1);if((g_board[from]&0xF)==pawn){moveStack[moveStack.length]=GenerateMove(from,g_enPassentSquare,moveflagEPC);}}
pieceIdx=(g_toMove|2)<<4;from=g_pieceList[pieceIdx++];while(from!=0){to=from+31;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from+33;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from+14;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from-14;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from-31;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from-33;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from+18;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from-18;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);from=g_pieceList[pieceIdx++];}
pieceIdx=(g_toMove|3)<<4;from=g_pieceList[pieceIdx++];while(from!=0){to=from;do{to-=15;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from;do{to-=17;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from;do{to+=15;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from;do{to+=17;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);from=g_pieceList[pieceIdx++];}
pieceIdx=(g_toMove|4)<<4;from=g_pieceList[pieceIdx++];while(from!=0){to=from;do{to--;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from;do{to++;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from;do{to-=16;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from;do{to+=16;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);from=g_pieceList[pieceIdx++];}
pieceIdx=(g_toMove|5)<<4;from=g_pieceList[pieceIdx++];while(from!=0){to=from;do{to-=15;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from;do{to-=17;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from;do{to+=15;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from;do{to+=17;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from;do{to--;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from;do{to++;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from;do{to-=16;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from;do{to+=16;}while(g_board[to]==0);if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);from=g_pieceList[pieceIdx++];}
{pieceIdx=(g_toMove|6)<<4;from=g_pieceList[pieceIdx];to=from-15;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from-17;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from+15;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from+17;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from-1;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from+1;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from-16;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);to=from+16;if(g_board[to]&enemy)moveStack[moveStack.length]=GenerateMove(from,to);}}
function MovePawnTo(moveStack,start,square){var row=square&0xF0;if((row==0x90)||(row==0x20)){moveStack[moveStack.length]=GenerateMove(start,square,moveflagPromotion|moveflagPromoteQueen);moveStack[moveStack.length]=GenerateMove(start,square,moveflagPromotion|moveflagPromoteKnight);moveStack[moveStack.length]=GenerateMove(start,square,moveflagPromotion|moveflagPromoteBishop);moveStack[moveStack.length]=GenerateMove(start,square,moveflagPromotion);}else{moveStack[moveStack.length]=GenerateMove(start,square,0);}}
function GeneratePawnMoves(moveStack,from){var piece=g_board[from];var color=piece&colorWhite;var inc=(color==colorWhite)?-16:16;var to=from+inc;if(g_board[to]==0){MovePawnTo(moveStack,from,to,pieceEmpty);if((((from&0xF0)==0x30)&&color!=colorWhite)||(((from&0xF0)==0x80)&&color==colorWhite)){to+=inc;if(g_board[to]==0){moveStack[moveStack.length]=GenerateMove(from,to);}}}}
function UndoHistory(ep,castleRights,inCheck,baseEval,hashKeyLow,hashKeyHigh,move50,captured){this.ep=ep;this.castleRights=castleRights;this.inCheck=inCheck;this.baseEval=baseEval;this.hashKeyLow=hashKeyLow;this.hashKeyHigh=hashKeyHigh;this.move50=move50;this.captured=captured;}
var g_seeValues=[0,1,3,3,5,9,900,0,0,1,3,3,5,9,900,0];function See(move){var from=move&0xFF;var to=(move>>8)&0xFF;var fromPiece=g_board[from];var fromValue=g_seeValues[fromPiece&0xF];var toValue=g_seeValues[g_board[to]&0xF];if(fromValue<=toValue){return true;}
if(move>>16){return true;}
var us=(fromPiece&colorWhite)?colorWhite:0;var them=8-us;var inc=(fromPiece&colorWhite)?-16:16;if(((g_board[to+inc+1]&0xF)==(piecePawn|them))||((g_board[to+inc-1]&0xF)==(piecePawn|them))){return false;}
var themAttacks=new Array();var captureDeficit=fromValue-toValue;SeeAddKnightAttacks(to,them,themAttacks);if(themAttacks.length!=0&&captureDeficit>g_seeValues[pieceKnight]){return false;}
g_board[from]=0;for(var pieceType=pieceBishop;pieceType<=pieceQueen;pieceType++){if(SeeAddSliderAttacks(to,them,themAttacks,pieceType)){if(captureDeficit>g_seeValues[pieceType]){g_board[from]=fromPiece;return false;}}}
if(((g_board[to-inc+1]&0xF)==(piecePawn|us))||((g_board[to-inc-1]&0xF)==(piecePawn|us))){g_board[from]=fromPiece;return true;}
SeeAddSliderAttacks(to,them,themAttacks,pieceKing);var usAttacks=new Array();SeeAddKnightAttacks(to,us,usAttacks);for(var pieceType=pieceBishop;pieceType<=pieceKing;pieceType++){SeeAddSliderAttacks(to,us,usAttacks,pieceType);}
g_board[from]=fromPiece;var seeValue=toValue-fromValue;for(;;){var capturingPieceValue=1000;var capturingPieceIndex=-1;for(var i=0;i<themAttacks.length;i++){if(themAttacks[i]!=0){var pieceValue=g_seeValues[g_board[themAttacks[i]]&0x7];if(pieceValue<capturingPieceValue){capturingPieceValue=pieceValue;capturingPieceIndex=i;}}}
if(capturingPieceIndex==-1){return true;}
seeValue+=capturingPieceValue;if(seeValue<0){return false;}
var capturingPieceSquare=themAttacks[capturingPieceIndex];themAttacks[capturingPieceIndex]=0;SeeAddXrayAttack(to,capturingPieceSquare,us,usAttacks,themAttacks);capturingPieceValue=1000;capturingPieceIndex=-1;for(var i=0;i<usAttacks.length;i++){if(usAttacks[i]!=0){var pieceValue=g_seeValues[g_board[usAttacks[i]]&0x7];if(pieceValue<capturingPieceValue){capturingPieceValue=pieceValue;capturingPieceIndex=i;}}}
if(capturingPieceIndex==-1){return false;}
seeValue-=capturingPieceValue;if(seeValue>=0){return true;}
capturingPieceSquare=usAttacks[capturingPieceIndex];usAttacks[capturingPieceIndex]=0;SeeAddXrayAttack(to,capturingPieceSquare,us,usAttacks,themAttacks);}}
function SeeAddXrayAttack(target,square,us,usAttacks,themAttacks){var index=square-target+128;var delta=-g_vectorDelta[index].delta;if(delta==0)
return;square+=delta;while(g_board[square]==0){square+=delta;}
if((g_board[square]&0x18)&&IsSquareOnPieceLine(target,square)){if((g_board[square]&8)==us){usAttacks[usAttacks.length]=square;}else{themAttacks[themAttacks.length]=square;}}}
function SeeAddKnightAttacks(target,us,attacks){var pieceIdx=(us|pieceKnight)<<4;var attackerSq=g_pieceList[pieceIdx++];while(attackerSq!=0){if(IsSquareOnPieceLine(target,attackerSq)){attacks[attacks.length]=attackerSq;}
attackerSq=g_pieceList[pieceIdx++];}}
function SeeAddSliderAttacks(target,us,attacks,pieceType){var pieceIdx=(us|pieceType)<<4;var attackerSq=g_pieceList[pieceIdx++];var hit=false;while(attackerSq!=0){if(IsSquareAttackableFrom(target,attackerSq)){attacks[attacks.length]=attackerSq;hit=true;}
attackerSq=g_pieceList[pieceIdx++];}
return hit;}
function BuildPVMessage(bestMove,value,timeTaken,ply){var totalNodes=g_nodeCount+g_qNodeCount;return "Ply:"+ply+" Score:"+value+" Nodes:"+totalNodes+" NPS:"+((totalNodes/(timeTaken/1000))|0)+" "+PVFromHash(bestMove,15);}
function FinishPlyCallback(bestMove,value,timeTaken,ply){postMessage("pv "+BuildPVMessage(bestMove,value,timeTaken,ply));}
function FinishMoveLocalTesting(bestMove,value,timeTaken,ply){if(bestMove!=null){MakeMove(bestMove);postMessage(FormatMove(bestMove));}}
var needsReset=true;self.onmessage=function(e){if(e.data=="go"||needsReset){ResetGame();needsReset=false;if(e.data=="go")return;}
if(e.data.match("^position")=="position"){ResetGame();var result=InitializeFromFen(e.data.substr(9,e.data.length-9));if(result.length!=0){postMessage("message "+result);}}else if(e.data.match("^search")=="search"){var parts=e.data.split(' ');if(parts.length>1)g_timeout=parts[1];if(parts.length>2)rp_ply=parts[2];if(parts.length>2)rp_rand=parts[3];Search(FinishMoveLocalTesting,rp_ply,FinishPlyCallback);}else if(e.data=="analyze"){g_timeout=99999999999;Search(null,rp_ply,FinishPlyCallback);}else if(e.data.match("^move")=="move"){MakeMove(GetMoveFromString(e.data.substr(5,e.data.length-5)));}}