{"id":60630,"date":"2023-09-03T03:01:39","date_gmt":"2023-09-02T17:01:39","guid":{"rendered":"http:\/\/www.rjmprogramming.com.au\/ITblog\/?p=60630"},"modified":"2023-09-03T19:14:50","modified_gmt":"2023-09-03T09:14:50","slug":"chess-game-check-logic-tutorial","status":"publish","type":"post","link":"https:\/\/www.rjmprogramming.com.au\/ITblog\/chess-game-check-logic-tutorial\/","title":{"rendered":"Chess Game Check Logic Tutorial"},"content":{"rendered":"
\"Chess<\/a>

Chess Game Check Logic Tutorial<\/p><\/div>\n

Finally, after the recent Chess Game Correspondence Tutorial<\/a>, today, we tackle …<\/p>\n


\nChess check logic
\n<\/code><\/p>\n

… regarding …<\/p>\n

\n
    \n
  • castling<\/font><\/li>\n
  • knowing when your King is in check or somebody has put your King in check<\/li>\n
  • knowing when an illegal move has happened regarding leaving your own King in check<\/li>\n
  • knowing when it’s Checkmate (or perhaps even Stalemate)<\/li>\n<\/ul>\n<\/blockquote>\n

    … and the illegal move whereby a King might get too close to the other King, we’re checking for within the same logic, working it that the Javascript global variable isbad<\/i> is set true<\/i> when a move is illegal because it puts your own King in check ..<\/p>\n


    \n function anybw(asq, thebrd, bwenemy, alertallowed) {
    \n thebrd+='&';
    \n isbad=false;
    \n iswrong=false;
    \n var bwfriend=bwenemy.replace('w','!').replace('b','W').replace('!', 'b').toLowerCase();
    \n var okfornow=true, startat=eval('' + asq), twos=[];
    \n var startrow=Math.floor(eval(-1 + asq) \/ 8);
    \n var startcol=Math.floor(eval(-1 + asq) % 8);
    \n var lastcol=-1, lastrow=-1;
    \n var kposa=[18,-18,17,-17,15,-15,6,-6,10,10];
    \n var pposa=[9,7];
    \n var kgposa=[9,8,7,-1,1,-7,-8,-9];
    \n var ikposa=0;
    \n if (asq == thissquare) {
    \n asq=asq;
    \n }
    \n if (bwfriend == 'w') {
    \n pposa=[-9,-7];
    \n }
    \n

    \n \/\/alert('Checking ' + bwfriend + ' King at ' + asq);
    \n
    \n \/\/ Horizontal check
    \n startat=eval(-1 + asq);
    \n while (startat >= 1 && startat <= 64 && startrow == Math.floor(eval(-1 + startat) \/ 8)) {
    \n if (thebrd.indexOf('_' + startat + 'w') != -1) {
    \n twos=thebrd.split('_' + startat + 'w');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('R') != -1) {
    \n isbad=true;
    \n \/\/alert(1);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + 'b') != -1) {
    \n twos=thebrd.split('_' + startat + 'b');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('R') != -1) {
    \n isbad=true;
    \n \/\/alert(2);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + '&') != -1) {
    \n twos=thebrd.split('_' + startat + '&');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('R') != -1) {
    \n isbad=true;
    \n \/\/alert(3);
    \n return asq;
    \n }
    \n }
    \n }
    \n startat--;
    \n }
    \n startat=eval(1 + asq);
    \n while (startat >= 1 && startat <= 64 && startrow == Math.floor(eval(-1 + startat) \/ 8)) {
    \n if (thebrd.indexOf('_' + startat + 'w') != -1) {
    \n twos=thebrd.split('_' + startat + 'w');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('R') != -1) {
    \n isbad=true;
    \n \/\/alert(11);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + 'b') != -1) {
    \n twos=thebrd.split('_' + startat + 'b');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('R') != -1) {
    \n isbad=true;
    \n \/\/alert(12);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + '&') != -1) {
    \n twos=thebrd.split('_' + startat + '&');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('R') != -1) {
    \n isbad=true;
    \n \/\/alert(13);
    \n return asq;
    \n }
    \n }
    \n }
    \n startat++;
    \n }
    \n
    \n \/\/ Vertical check
    \n startat=eval(-8 + asq);
    \n while (startat >= 1 && startat <= 64 && startcol == Math.floor(eval(-1 + startat) % 8)) {
    \n if (thebrd.indexOf('_' + startat + 'w') != -1) {
    \n twos=thebrd.split('_' + startat + 'w');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('R') != -1) {
    \n isbad=true;
    \n \/\/alert(21);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + 'b') != -1) {
    \n twos=thebrd.split('_' + startat + 'b');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('R') != -1) {
    \n isbad=true;
    \n \/\/alert(22);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + '&') != -1) {
    \n twos=thebrd.split('_' + startat + '&');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('R') != -1) {
    \n isbad=true;
    \n \/\/alert(23);
    \n return asq;
    \n }
    \n }
    \n }
    \n startat-=8;
    \n }
    \n startat=eval(8 + asq);
    \n while (startat >= 1 && startat <= 64 && startcol == Math.floor(eval(-1 + startat) % 8)) {
    \n if (thebrd.indexOf('_' + startat + 'w') != -1) {
    \n twos=thebrd.split('_' + startat + 'w');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('R') != -1) {
    \n isbad=true;
    \n \/\/alert(24);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + 'b') != -1) {
    \n twos=thebrd.split('_' + startat + 'b');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('R') != -1) {
    \n isbad=true;
    \n \/\/alert(25);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + '&') != -1) {
    \n twos=thebrd.split('_' + startat + '&');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('R') != -1) {
    \n isbad=true;
    \n \/\/alert(26);
    \n return asq;
    \n }
    \n }
    \n }
    \n startat+=8;
    \n }
    \n
    \n \/\/ Diagonal check
    \n lastcol=Math.floor(eval(-1 + asq) % 8);
    \n lastrow=Math.floor(eval(-1 + asq) \/ 8);
    \n startat=eval(-9 + asq);
    \n while (startat >= 1 && startat <= 64 && Math.abs(lastcol - Math.floor(eval(-1 + startat) % 8)) == 1 && Math.abs(lastrow - Math.floor(eval(-1 + startat) \/ 8)) == 1) {
    \n if (thebrd.indexOf('_' + startat + 'w') != -1) {
    \n twos=thebrd.split('_' + startat + 'w');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('B') != -1) {
    \n isbad=true;
    \n \/\/alert('31 ' + bwfriend + ' ' + twos[0].slice(-3) + ' ' + startat + ' ' + asq);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + 'b') != -1) {
    \n twos=thebrd.split('_' + startat + 'b');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('B') != -1) {
    \n isbad=true;
    \n \/\/alert(32);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + '&') != -1) {
    \n twos=thebrd.split('_' + startat + '&');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('B') != -1) {
    \n isbad=true;
    \n \/\/alert(33);
    \n return asq;
    \n }
    \n }
    \n }
    \n lastcol=Math.floor(eval(-1 + startat) % 8);
    \n lastrow=Math.floor(eval(-1 + startat) \/ 8);
    \n startat-=9;
    \n }
    \n lastcol=Math.floor(eval(-1 + asq) % 8);
    \n lastrow=Math.floor(eval(-1 + asq) \/ 8);
    \n startat=eval(-7 + asq);
    \n while (startat >= 1 && startat <= 64 && Math.abs(lastcol - Math.floor(eval(-1 + startat) % 8)) == 1 && Math.abs(lastrow - Math.floor(eval(-1 + startat) \/ 8)) == 1) { \/\/ && startcol == Math.floor(eval(-1 + startat) % 8)) {
    \n if (thebrd.indexOf('_' + startat + 'w') != -1) {
    \n twos=thebrd.split('_' + startat + 'w');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('B') != -1) {
    \n isbad=true;
    \n \/\/alert(41);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + 'b') != -1) {
    \n twos=thebrd.split('_' + startat + 'b');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('B') != -1) {
    \n isbad=true;
    \n \/\/alert(42);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + '&') != -1) {
    \n twos=thebrd.split('_' + startat + '&');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('B') != -1) {
    \n isbad=true;
    \n \/\/alert(43);
    \n return asq;
    \n }
    \n }
    \n }
    \n lastcol=Math.floor(eval(-1 + startat) % 8);
    \n lastrow=Math.floor(eval(-1 + startat) \/ 8);
    \n startat-=7;
    \n }
    \n lastcol=Math.floor(eval(-1 + asq) % 8);
    \n lastrow=Math.floor(eval(-1 + asq) \/ 8);
    \n startat=eval(9 + asq);
    \n while (startat >= 1 && startat <= 64 && Math.abs(lastcol - Math.floor(eval(-1 + startat) % 8)) == 1 && Math.abs(lastrow - Math.floor(eval(-1 + startat) \/ 8)) == 1) { \/\/ && startcol == Math.floor(eval(-1 + startat) % 8)) {
    \n if (thebrd.indexOf('_' + startat + 'w') != -1) {
    \n twos=thebrd.split('_' + startat + 'w');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('B') != -1) {
    \n isbad=true;
    \n \/\/alert(44);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + 'b') != -1) {
    \n twos=thebrd.split('_' + startat + 'b');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('B') != -1) {
    \n isbad=true;
    \n \/\/alert(45);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + '&') != -1) {
    \n twos=thebrd.split('_' + startat + '&');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('B') != -1) {
    \n isbad=true;
    \n \/\/alert(46);
    \n return asq;
    \n }
    \n }
    \n }
    \n lastcol=Math.floor(eval(-1 + startat) % 8);
    \n lastrow=Math.floor(eval(-1 + startat) \/ 8);
    \n startat+=9;
    \n }
    \n lastcol=Math.floor(eval(-1 + asq) % 8);
    \n lastrow=Math.floor(eval(-1 + asq) \/ 8);
    \n startat=eval(7 + asq);
    \n while (startat >= 1 && startat <= 64 && Math.abs(lastcol - Math.floor(eval(-1 + startat) % 8)) == 1 && Math.abs(lastrow - Math.floor(eval(-1 + startat) \/ 8)) == 1) { \/\/ && startcol == Math.floor(eval(-1 + startat) % 8)) {
    \n \/\/alert('checking square ' + startat);
    \n if (thebrd.indexOf('_' + startat + 'w') != -1) {
    \n twos=thebrd.split('_' + startat + 'w');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('B') != -1) {
    \n isbad=true;
    \n \/\/alert(51);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + 'b') != -1) {
    \n twos=thebrd.split('_' + startat + 'b');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('B') != -1) {
    \n isbad=true;
    \n \/\/alert(52);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + '&') != -1) {
    \n twos=thebrd.split('_' + startat + '&');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n break;
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('Q') != -1 || twos[0].slice(-3).indexOf('B') != -1) {
    \n isbad=true;
    \n \/\/alert(53);
    \n return asq;
    \n }
    \n }
    \n }
    \n lastcol=Math.floor(eval(-1 + startat) % 8);
    \n lastrow=Math.floor(eval(-1 + startat) \/ 8);
    \n startat+=7;
    \n }
    \n
    \n \/\/ Knight check
    \n for (ikposa=0; ikposa<kposa.length; ikposa++) {
    \n startat=eval(kposa[ikposa] + asq);
    \n if (startat >= 1 && startat <= 64 && startrow != Math.floor(eval(-1 + startat) \/ 8) && startcol != Math.floor(eval(-1 + startat) % 8)) {
    \n if (thebrd.indexOf('_' + startat + 'w') != -1) {
    \n twos=thebrd.split('_' + startat + 'w');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n twos[0]=twos[0];
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('K1') != -1 || twos[0].slice(-3).indexOf('K2') != -1) {
    \n isbad=true;
    \n \/\/alert(61);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + 'b') != -1) {
    \n twos=thebrd.split('_' + startat + 'b');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n twos[0]=twos[0];
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('K1') != -1 || twos[0].slice(-3).indexOf('K2') != -1) {
    \n isbad=true;
    \n \/\/alert(62);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + '&') != -1) {
    \n twos=thebrd.split('_' + startat + '&');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n twos[0]=twos[0];
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('K1') != -1 || twos[0].slice(-3).indexOf('K2') != -1) {
    \n isbad=true;
    \n \/\/alert(63);
    \n return asq;
    \n }
    \n }
    \n }
    \n }
    \n }
    \n
    \n \/\/ Pawn check
    \n for (ikposa=0; ikposa<pposa.length; ikposa++) {
    \n startat=eval(pposa[ikposa] + asq);
    \n if (startat >= 1 && startat <= 64 && startrow != Math.floor(eval(-1 + startat) \/ 8) && startcol != Math.floor(eval(-1 + startat) % 8)) {
    \n if (thebrd.indexOf('_' + startat + 'w') != -1) {
    \n twos=thebrd.split('_' + startat + 'w');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n twos[0]=twos[0];
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('P') != -1) {
    \n isbad=true;
    \n \/\/alert(71);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + 'b') != -1) {
    \n twos=thebrd.split('_' + startat + 'b');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n twos[0]=twos[0];
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('P') != -1) {
    \n isbad=true;
    \n \/\/alert(72);
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + '&') != -1) {
    \n twos=thebrd.split('_' + startat + '&');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n twos[0]=twos[0];
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('P') != -1) {
    \n isbad=true;
    \n \/\/alert(73);
    \n return asq;
    \n }
    \n }
    \n }
    \n }
    \n }
    \n

    \n \/\/ King too near King check
    \n for (ikgposa=0; ikgposa<kgposa.length; ikgposa++) {
    \n startat=eval(kgposa[ikgposa] + asq);
    \n if (startat >= 1 && startat <= 64 && startrow != Math.floor(eval(-1 + startat) \/ 8) && startcol != Math.floor(eval(-1 + startat) % 8)) {
    \n if (thebrd.indexOf('_' + startat + 'w') != -1) {
    \n twos=thebrd.split('_' + startat + 'w');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n twos[0]=twos[0];
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('K') != -1 && twos[0].slice(-3).indexOf('K1') == -1 && twos[0].slice(-3).indexOf('K2') == -1) {
    \n iswrong=true;
    \n if (alertallowed) { alert('Kings can not be this close together.'); }
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + 'b') != -1) {
    \n twos=thebrd.split('_' + startat + 'b');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n twos[0]=twos[0];
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('K') != -1 && twos[0].slice(-3).indexOf('K1') == -1 && twos[0].slice(-3).indexOf('K2') == -1) {
    \n iswrong=true;
    \n if (alertallowed) { alert('Kings can not be this close together.'); }
    \n return asq;
    \n }
    \n }
    \n } else if (thebrd.indexOf('_' + startat + '&') != -1) {
    \n twos=thebrd.split('_' + startat + '&');
    \n if (twos[0].slice(-3).indexOf(bwfriend) != -1) {
    \n twos[0]=twos[0];
    \n } else if (twos[0].slice(-3).indexOf(bwenemy) != -1) {
    \n if (twos[0].slice(-3).indexOf('K') != -1 && twos[0].slice(-3).indexOf('K1') == -1 && twos[0].slice(-3).indexOf('K2') == -1) {
    \n iswrong=true;
    \n if (alertallowed) { alert('Kings can not be this close together.'); }
    \n return asq;
    \n }
    \n }
    \n }
    \n }
    \n }
    \n
    \n return asq;
    \n }
    \n<\/code><\/p>\n

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