{ "information": { "Title": "ejss_model_guards_riddle Guard's Riddle, game to position numbers apart by the number they are in", "Author": [ "Shaun Quek", "Loo Kang Wee", "Francisco Esquembre", "F\u00e9lix Jes\u00fas Garc\u00eda Clemente.", "based on idea by Theresa Heng" ], "AuthorLogo": [ "", "", "", "", "" ], "Password": "", "Keywords": "", "Abstract": "picture of guard is from powerpoint defult images.\npermission to use given by microsoft", "Copyright": "", "Level": "", "Language": "", "Logo": [ "./guards_riddle/Screenshot 2021-06-05 at 12.30.53 PM.png" ], "RunAlways": "true", "ModelTab": "", "ModelTabTitle": "", "ModelName": "", "FixedNavigationBar": "false", "CSSFile": "", "DetectedFiles": [ "./guards_riddle/Screenshot 2021-06-05 at 12.30.53 PM.png" ], "AuxiliaryFiles": [ "./guards_riddle/" ], "HTMLHead": "\n\n\n", "SaveInXMLFormat": "false", "IncludeSource": "true", "IncludeLibrary": "true", "UglifyJS": "false", "PreviewFullModel": "false", "UseInterpreter": "true", "UseDeltaForODE": "false" }, "description": { "pages": [ { "Name": "Intro Page", "Active": "true", "Internal": "false", "Type": "DESCRIPTION_EDITOR", "Locale": "_default_", "Title": "Intro Page", "External": "false", "Code": "\n\n\n

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i < n * 2; i++){\n guardX.push(i * guardWidth), guardY.push(guardHeight);\n initGuardX.push(i * guardWidth);\n guardVal.push(parseInt(i / 2) + 1);\n guardPos.push(-1);\n boxX.push(i * guardWidth), boxY.push(-guardHeight);\n boxPos.push(i);\n boxOccupied.push(false);\n boxFillColor.push('#FFD700');\n textStr.push(parseInt(i / 2) + 1);\n}\n\n// Reset solver state on every reset\nif (typeof _solverTimer !== 'undefined' && _solverTimer) { clearTimeout(_solverTimer); _solverTimer = null; }\nif (typeof _solverRunning !== 'undefined') { _solverRunning = false; _solverPaused = false; _solverIdx = 0; _solverSteps = []; }\nif (typeof _updateSolverUI === 'function') _updateSolverUI(null);\n\n// Expose solver API to HTML buttons (guard against double-init on reset)\nif (!window._solver || !window._solver._initialized) {\n window._solver = {\n _delay: 400, _initialized: true,\n start: function() { _startSolve(); },\n togglePause: function() { _togglePause(); },\n step: function() { _stepOnce(); },\n reset: function() { _resetSolverMode(); },\n setSpeed: function(val) {\n var d=[2000,1200,700,400,200,120,70,30,10];\n var l=['Slowest','Very Slow','Slow','Medium','Normal','Fast','Very Fast','Super Fast','Instant'];\n var idx=Math.max(0,Math.min(8,parseInt(val)-1));\n window._solver._delay=d[idx];\n var lbl=document.getElementById('speedLabel'); if(lbl) lbl.textContent=l[idx];\n }\n };\n}" } ] }, "evolution": { "information": { "FPS": "20", "SPD": "1", "RealTimeVariable": "", "Autoplay": "true" }, "pages": [] }, "fixed_relations": { "pages": [] }, "custom": { "pages": [ { "Name": "Lib Page", "Active": "true", "Internal": "false", "Type": "LIBRARY_EDITOR", "Comment": "", "Code": "//https://developer.mozilla.org/en-US/docs/Web/Guide/API/DOM/Using_full_screen_mode\nfunction toggleFullScreen() {\n if (!document.fullscreenElement && !document.mozFullScreenElement && !document.webkitFullscreenElement && !document.msFullscreenElement) {\n if (document.documentElement.requestFullscreen) { document.documentElement.requestFullscreen(); }\n else if (document.documentElement.msRequestFullscreen) { document.documentElement.msRequestFullscreen(); }\n else if (document.documentElement.mozRequestFullScreen) { document.documentElement.mozRequestFullScreen(); }\n else if (document.documentElement.webkitRequestFullscreen) { document.documentElement.webkitRequestFullscreen(); }\n } else {\n if (document.exitFullscreen) { document.exitFullscreen(); }\n else if (document.msExitFullscreen) { document.msExitFullscreen(); }\n else if (document.mozCancelFullScreen) { document.mozCancelFullScreen(); }\n else if (document.webkitExitFullscreen) { document.webkitExitFullscreen(); }\n }\n}\n\n// === SOLVER ENGINE (Backtracking) ===\nvar _solverSteps, _solverIdx, _solverRunning, _solverPaused, _solverTimer;\n\n// Pre-compute every TRY / BACK / SOLVED / NONE step for the backtracking search\nfunction _buildSteps(numN) {\n var steps = [], board = new Array(2*numN).fill(0), tries = 0, backtracks = 0;\n function bt(rank) {\n if (rank > numN) {\n steps.push({type:'SOLVED',board:board.slice(),tries:tries,backtracks:backtracks,p1:-1,p2:-1,rank:rank});\n return true;\n }\n for (var p1 = 0; 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\n\n \n\n \n\n \n\n
" }, { "name": "Width", "value": "\"30%\"" }, { "name": "Display", "value": "showHint?\"inline\":\"none\"" } ] }, { "Name": "label", "Type": "Label", "Properties": [ { "name": "Text", "value": "\"Rank: 1 to\"" }, { "name": "Width", "value": "\"30%\"" }, { "name": "Font", "value": "font" } ] }, { "Name": "comboBox", "Type": "ComboBox", "Properties": [ { "name": "Options", "value": "[3, 4, 5, 6, 7, 8]" }, { "name": "OnChange", "value": "var selected = _view.comboBox.getProperty(\"SelectedOptions\")[0];\nn = parseInt(selected);\n_reset();\n" }, { "name": "Width", "value": "\"30%\"" }, { "name": "Font", "value": "font" } ] }, { "Name": "reset", "Type": "Button", "Properties": [ { "name": "Text", "value": "\"\u21bbReset\"" }, { "name": "OnClick", "value": "_reset();" }, { "name": "Width", "value": "\"30%\"" }, { "name": "Font", "value": "font" } ] } ] }, { "Name": "mainPanel", "Type": "Panel", "Expanded": "true", "Properties": [], "Children": [ { "Name": "plottingPanel", "Type": "PlottingPanel", "Expanded": "true", "Properties": [ { "name": "Gutters", "value": "[0, 0, 0, 0]" }, { "name": "YScalePrecision", "value": "2" }, { "name": "XFixedTick", "value": "0.5" }, { "name": "Enabled", "value": "true" }, { "name": "OnDoubleClick", "value": "toggleFullScreen()" }, { "name": "SquareAspect", "value": "true" }, { "name": "MaximumY", "value": "guardHeight * 3 / 2" }, { "name": "MaximumX", "value": "guardWidth * n * 2" }, { "name": "YFixedTick", "value": "guardY[0]+guardHeight/2" }, { "name": "YAutoTicks", "value": "false" }, { "name": "MinimumX", "value": "-guardWidth" }, { "name": "MinimumY", "value": "-guardHeight * 3 / 2" }, { "name": "XTickStep", "value": "1" }, { "name": "YTickStep", "value": "guardY[0]+guardHeight/2" }, { "name": "XAutoTicks", "value": "false" }, { "name": "Height", "value": "\"80vh\"" }, { "name": "XScalePrecision", "value": "1" }, { "name": "Width", "value": "\"100%\"" }, { "name": "TLMessage", "value": "solverMessage" } ], "Children": [ { "Name": "boxSet", "Type": "ShapeSet2D", "Properties": [ { "name": "NumberOfElements", "value": "n * 2" }, { "name": "FillColor", "value": "boxFillColor" }, { "name": "SizeX", "value": "guardWidth" }, { "name": "ShapeType", "value": "\"RECTANGLE\"" }, { "name": "X", "value": "boxX" }, { "name": "Y", "value": "boxY" }, { "name": "SizeY", "value": "guardHeight" } ] }, { "Name": "guardSet", "Type": "ShapeSet2D", "Properties": [ { "name": "NumberOfElements", "value": "n * 2" }, { "name": "OnRelease", "value": "var x = guardX[interact], y = guardY[interact];\nvar choosenBox = -1, minDist = thresholdDist * 2;\nfor(var i = 0; i < n * 2; i++){\n if(boxOccupied[i]) continue;\n var curX = boxX[i], curY = boxY[i];\n var dist = (curX - x) ** 2 + (curY - y) ** 2;\n if(dist <= minDist){ choosenBox = i; minDist = dist; }\n}\nif(guardPos[interact] != -1){\n boxOccupied[guardPos[interact]] = false;\n boxFillColor[guardPos[interact]] = '#FFD700';\n score--;\n}\nvar pairCard = interact % 2 == 0 ? interact + 1 : interact - 1;\nif(choosenBox != -1 && (guardPos[pairCard] == -1 || Math.abs(guardPos[pairCard] - boxPos[choosenBox]) == guardVal[interact])){\n guardX[interact] = boxX[choosenBox];\n guardY[interact] = boxY[choosenBox];\n boxOccupied[choosenBox] = true;\n boxFillColor[choosenBox] = '#87CEEB';\n guardPos[interact] = boxPos[choosenBox];\n score++;\n if(score == n * 2){\n _tools.showOkDialog(\"Congratulations, you managed to arrange all the guards correctly!\");\n }\n} else {\n guardX[interact] = initGuardX[interact];\n guardY[interact] = guardHeight;\n guardPos[interact] = -1;\n}" }, { "name": "FillColor", "value": "\"rgba(200,220,208,1)\"" }, { "name": "Sensitivity", "value": "0" }, { "name": "SizeX", "value": "guardWidth" }, { "name": "ShapeType", "value": "\"RECTANGLE\"" }, { "name": "X", "value": "guardX" }, { "name": "Y", "value": "guardY" }, { "name": "SizeY", "value": "guardHeight" }, { "name": "EnabledPosition", "value": "\"ENABLED_ANY\"" }, { "name": "ElementInteracted", "value": "interact" } ] }, { "Name": "textSet", "Type": "TextSet2D", "Properties": [ { "name": "NumberOfElements", "value": "n * 2" }, { "name": "X", "value": "guardX" }, { "name": "Y", "value": "guardY" }, { "name": "Text", "value": "textStr" }, { "name": "Font", "value": "font" } ] }, { "Name": "offset", "Type": "Group2D", "Expanded": "false", "Properties": [], "Children": [ { "Name": "imageSet", "Type": "ImageSet2D", "Properties": [ { "name": "NumberOfElements", "value": "n * 2" }, { "name": "SizeX", "value": "guardWidth" }, { "name": "X", "value": "guardX" }, { "name": "Y", "value": "guardY" }, { "name": "ImageUrl", "value": "imageurl" }, { "name": "SizeY", "value": "guardHeight" } ] } ] } ] } ] }, { "Name": "html", "Type": "Panel", "Properties": [ { "name": "Html", "value": "

Instructions: Choose the number of guard ranks and drag each guard into the yellow boxes.

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Rule: Two guards of rank k must be placed exactly k boxes apart (|pos2 - pos1| = k). Example: two Rank-3 guards must be 3 positions apart.

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\n \ud83c\udfaf Goal: Place all 2n guards into the numbered boxes below\n so that every pair follows the spacing rule.\n

\n\n
\n \ud83d\udccf The Rule: The two guards of rank k must be placed\n exactly k boxes apart.
\n Formally:  |position\u2082 \u2212 position\u2081| = k\n
\n\n \ud83d\udcd6 Example (n = 4, boxes numbered 1\u20138):\n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n
Box #12345678
Guard41134232
\n\n
    \n
  • Rank 1 at boxes 2 & 3 \u2192 apart by 1 \u2713
    • \n
  • Rank 2 at boxes 6 & 8 \u2192 apart by 2 \u2713
    • \n
  • Rank 3 at boxes 4 & 7 \u2192 apart by 3 \u2713
    • \n
  • Rank 4 at boxes 1 & 5 \u2192 apart by 4 \u2713
    • \n
\n\n

\n \ud83d\udca1 Drag a guard from the top row into a yellow box below.\n Invalid placements snap back automatically.\n Use Auto-Solve below to watch the computer find the solution step by step!\n

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" } ] }, { "Name": "solverPanel", "Type": "Panel", "Expanded": "true", "Properties": [ { "name": "Html", "value": "
\n\n

\n \ud83e\udd16 Computer Solver \u2014 Watch the Thinking Process\n

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\n About: The computer uses backtracking search \u2014 it tries each placement in order. If stuck, it undoes the last move and tries the next option (like navigating a maze by always going back when you hit a dead-end).\n
Colour code:\n green = trying now\n  \n pink = backtracked\n  \n blue = placed on path\n
\n\n \n
\n Step: 0 / 0\n Tries: 0\n Backtracks: 0\n
\n\n \n
\n Press Auto-Solve or One Step to start.\n
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\n \n \ud83d\udccb Step Log (click to expand)\n \n\n
\n \n
\n\n
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\n\n \n
\n \ud83e\udde0 When does a solution exist?
\n n=3 \u274c   n=4 \u2705 (4 1 1 3 4 2 3 2)   n=5 \u2705 (2 3 2 5 3 4 1 1 5 4)   n=6 \u274c   n=7 \u274c   n=8 \u2705\n\n
\n Reveal the pattern\n Solutions exist when n mod 4 = 0 or 3 (standard Langford problem). Backtracking proves no solution by exhaustively testing every possibility.\n
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