<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title></title>
<style type="text/css">
body
{
font-size: 0.9em;
font-family: verdana, arial, sans-serif;
background-color: #FAEBD7;
}
button
{
width: 90px;
margin-top: 8px;
}
canvas
{
background-color: #fffff0;
padding-bottom:10px;
display:block;
}
#sudoku
{
margin-left:auto;
margin-right:auto;
width: 945px;
height:900px;
background-color: #fefefe;
padding:10px;
}
#banner
{
position: relative;
left: 0px;
top:0px;
padding: 10px;
}
#help
{
top:60px;
font-size: 10px;
width: 220px;
float: right;
}
#main
{
top:60px;
padding: 10px;
float:left;
}
#big
{
font-size: 32px;
color:#448844;
}
#small
{
display:block;
font-size: 10px;
}
#help li
{
padding-bottom: 6px;
}
h2
{
color: #444444;
text-align:center;
}
td.help li
{
padding-bottom: 6px;
font-size: 0.7em;
}
</style>
<script type="text/javascript" >
// Please leave this notice intact.
// Code developed by Ron de Jong 2011.
// You are free to use this code for whatever purpose.
// Converts global co-ords used in mouse events to relative to element
function relMouseCoords(event) {
var totalOffsetX = 0;
var totalOffsetY = 0;
var canvasX = 0;
var canvasY = 0;
var currentElement = this;
do {
totalOffsetX += currentElement.offsetLeft;
totalOffsetY += currentElement.offsetTop;
}
while (currentElement = currentElement.offsetParent)
canvasX = event.pageX - totalOffsetX;
canvasY = event.pageY - totalOffsetY;
return { x: canvasX, y: canvasY }
}
HTMLCanvasElement.prototype.relMouseCoords = relMouseCoords;
// Javascript doesn't have 'contains' so added here for later readability
Array.prototype.contains = function (element) {
for (var i = 0; i < this.length; i++) {
if (this[i] == element) {
return true;
}
}
return false;
}
var SquareSize = 3;
var BoardSize = SquareSize * SquareSize;
function AllowedValues(n) {
this._mask = n;
}
AllowedValues.prototype.getSingle = function () {
// Count number of on bits from 1..9
var single = 0;
var count = 0;
for (var i = 1; i <= BoardSize; i++)
if ((this._mask & (1 << i)) != 0) {
count++;
single = i;
}
return count == 1 ? single : 0;
};
// Used when the answer is known at the Cell, level this sets the only allowed value to be that answer
AllowedValues.prototype.setSingle = function (n) {
this._mask = 1 << n;
};
AllowedValues.prototype.count = function () {
// Count number of on bits from 1..9
var count = 0;
for (var i = 1; i <= BoardSize; i++)
if ((this._mask & (1 << i)) != 0)
count++;
return count;
};
AllowedValues.prototype.isAllowed = function (n) {
return n >= 1 && n <= BoardSize && ((this._mask & (1 << n)) != 0);
};
AllowedValues.prototype.removeValues = function (bm) {
this._mask &= ~bm._mask;
};
AllowedValues.prototype.allowedValuesArray = function () {
var ret = new Array();
for (var i = 1; i <= BoardSize; i++)
if (((1 << i) & this._mask) != 0)
ret.push(i);
return ret;
};
AllowedValues.prototype.clone = function () {
return new AllowedValues(this._mask);
};
function Cell(value) {
this._value = value; // 0 means unassigned
this._allowed = new AllowedValues(0x3e); // all possible
this._answer = 0; // no answer
this._given = false;
}
Cell.prototype.clone = function (value) {
var clone = new Cell();
clone._value = this._value;
clone._allowed = this._allowed.clone();
clone._answer = this._answer;
clone._given = this._given;
return clone;
};
Cell.prototype.single = function (value) {
this._value = value; // value user (or auto solve functions) has assigned as a possible answer
this._allowed = new AllowedValues(0x3e); // the allowed values as a bit mask
this._answer = 0; // calculated as the only possible correct value
};
Cell.prototype.valueMask = function () {
return this._value == 0 ? 0 : 1 << this._value;
};
Cell.prototype.hasAnswer = function () {
return this._answer != 0;
};
Cell.prototype.getAnswer = function () {
return this._answer;
};
Cell.prototype.setAnswer = function (n) {
if (n < 0 || n > 9)
throw "Illegal value not in the range 1..9.";
this._answer = n;
};
Cell.prototype.getValue = function () {
return this._value;
};
Cell.prototype.setValue = function (n) {
if (n < 0 || n > 9)
throw "Illegal value not in the range 1..9.";
if (n != 0 && !this._allowed.isAllowed(n))
throw "Not allowed.";
this._value = n;
this._given = false;
};
Cell.prototype.setGiven = function (n) {
if (n < 0 || n > 9)
throw "Illegal value not in the range 1..9.";
this._value = n;
this._given = n != 0;
this._answer = 0;
};
Cell.prototype.isGiven = function () {
return this._given;
};
Cell.prototype.isAssigned = function () {
return this._value != 0;
};
Cell.prototype.clear = function () {
this._value = 0; // means unassigned
this._allowed = new AllowedValues(0x3E); // all possible
this._answer = 0;
this._given = 0;
};
Cell.prototype.isAllowed = function (value) {
return this._allowed.isAllowed(value);
};
Cell.prototype.setAllowed = function (value) {
this._allowed = new AllowedValues(value);
};
Cell.prototype.getAllowedClone = function (value) {
return this._allowed.clone();
};
var SibType = { "Row": 1, "Col": 2, "Square": 3 };
function Location(row, col) {
this.row = row;
this.col = col;
}
Location.empty = new Location(-1, -1);
Location.prototype.isEmpty = function () {
return this.row < 0;
};
Location.prototype.modulo = function (n) {
if (n < 0)
return n + BoardSize;
return n % BoardSize;
};
Location.prototype.left = function () {
return new Location(this.row, this.modulo(this.col - 1));
};
Location.prototype.right = function () {
return new Location(this.row, this.modulo(this.col + 1));
};
Location.prototype.up = function () {
return new Location(this.modulo(this.row - 1), this.col);
};
Location.prototype.down = function () {
return new Location(this.modulo(this.row + 1), this.col);
};
Location.prototype.toString = function () {
return "Row=" + String(this.row) + "Col=" + String(this.col);
};
Location.prototype.getSquare = function () {
return 3 * Math.floor(this.row / 3) + Math.floor(this.col / 3);
};
Location.prototype.equals = function (a) {
return a.row == this.row && a.col == this.col;
};
Location.prototype.notEquals = function (a) {
return a.row != this.row || a.col != this.col;
};
// Enumerator for locations of all cells
Location.grid = function () {
var locs = new Array();
for (var i = 0; i < BoardSize; i++)
for (var j = 0; j < BoardSize; j++)
locs.push(new Location(i, j));
return locs;
};
// Enumerator for locations of cell siblings in the same row
Location.prototype.rowSibs = function () {
var locs = new Array();
for (var i = 0; i < BoardSize; i++)
if (i != this.col)
locs.push(new Location(this.row, i));
return locs;
};
// Enumerator for locations of cell siblings in the same column
Location.prototype.colSibs = function () {
var locs = new Array();
for (var i = 0; i < BoardSize; i++)
if (i != this.row)
locs.push(new Location(i, this.col));
return locs;
};
// Enumerator for locations of cell siblings in the same square
Location.prototype.squareSibs = function () {
var locs = new Array();
var baseRow = 3 * Math.floor(this.row / 3); // this is how to convert float to an "int" - Javascript doesn't have ints!
var baseCol = 3 * Math.floor(this.col / 3);
for (var i = 0; i < SquareSize; i++) {
var r = baseRow + i;
for (var j = 0; j < SquareSize; j++) {
var c = baseCol + j;
if (r != this.row || c != this.col)
locs.push(new Location(r, c));
}
}
return locs;
};
Location.prototype.getSibs = function (type) {
switch (type) {
case SibType.Row:
return this.rowSibs();
case SibType.Col:
return this.colSibs();
case SibType.Square:
return this.squareSibs();
}
};
function Board() {
function MultiDimArray(rows, cols) {
var a = new Array(rows);
for (var i = 0; i < rows; i++) {
a[i] = new Array(cols);
for (var j = 0; j < cols; j++)
a[i][j] = new Cell();
}
return a;
}
this._digits = MultiDimArray(BoardSize, BoardSize);
this._isSolved = false;
this._isValid = false;
}
Board.prototype.clone = function () {
var clone = new Board();
clone._isSolved = this._isSolved;
clone._isValid = this._isValid;
clone._digits = new Array(BoardSize);
for (var i = 0; i < BoardSize; i++) {
clone._digits[i] = new Array(BoardSize);
for (var j = 0; j < BoardSize; j++)
clone._digits[i][j] = this._digits[i][j].clone();
}
return clone;
};
Board.prototype.copyTo = function (target) {
target._isSolved = this._isSolved;
target._isValid = this._isValid;
for (var i = 0; i < BoardSize; i++)
for (var j = 0; j < BoardSize; j++)
target._digits[i][j] = this._digits[i][j].clone();
};
Board.prototype.getCell = function (loc) {
return this._digits[loc.row][loc.col];
};
Board.prototype.setCell = function (loc, value) {
this._digits[loc.row][loc.col] = value;
};
Board.prototype.clear = function () {
for (var i = 0; i < BoardSize; i++)
for (var j = 0; j < BoardSize; j++)
this._digits[i][j].clear();
this.updateAllowed();
};
Board.prototype.reset = function () {// return Baord to only the givens
for (var i = 0; i < BoardSize; i++)
for (var j = 0; j < BoardSize; j++) {
var cell = this._digits[i][j];
if (!cell.isGiven())
cell.clear();
}
this.updateAllowed();
};
Board.prototype.checkIsValidSibs = function (loc, digit, locs) {
for (var i = 0; i < locs.length; i++) {
var loc = locs[i];
var cell = this._digits[loc.row][loc.col];
if (cell.getAnswer() == digit)
return false;
}
return true;
};
Board.prototype.checkIsValid = function (loc, digit) {
// Checks if the digit can go in that location by checking it doesn't
// exist in either the row, col or square siblings
if (!this.checkIsValidSibs(loc, digit, loc.colSibs()))
return false;
if (!this.checkIsValidSibs(loc, digit, loc.rowSibs()))
return false;
if (!this.checkIsValidSibs(loc, digit, loc.squareSibs()))
return false;
return true;
};
Board.prototype.acceptPossibles = function () {
var more = false;
var locs = Location.grid();
for (var i = 0; i < locs.length; i++) {
var loc = locs[i];
var cell = this._digits[loc.row][loc.col];
if (!cell.isAssigned() && cell.hasAnswer() && this.checkIsValid(loc, cell.getAnswer())) {
cell.setValue(cell.getAnswer()); // if unassigned and has the answer then assign the answer
more = true;
}
}
return more;
};
Board.prototype.checkForHiddenSingles = function (loc, st) {
// Check each cell - if not assigned and has no answer then check its siblings
// get all its allowed then remove all the allowed
var cell = this.getCell(loc);
if (!cell.isAssigned() && !cell.hasAnswer()) {
var allowed = cell.getAllowedClone(); // copy of bit mask of allowed values for this cell
var locs = loc.getSibs(st);
for (var i = 0; i < locs.length; i++) {
var sib = locs[i];
var sibCell = this.getCell(sib);
if (!sibCell.isAssigned())
allowed.removeValues(sibCell.getAllowedClone()); // remove allowed values from siblings
}
var answer = allowed.getSingle(); // if there is only one allowed value left (i.e. this cell is the only one amonsgt its sibs with this allowed value)
// then apply it as the answer. Note getSingle will return 0 (i.e. no anser) if the number of allowed values is not exactly one
if (answer != 0) {
cell.setAnswer(answer);
return true; // no need to check others sibling collections
}
}
return false;
};
Board.prototype.findCellWithFewestChoices = function () {
var minLocation = Location.empty;
var minCount = 9;
var locs = Location.grid();
for (var i = 0; i < locs.length; i++) {
var loc = locs[i];
var cell = this.getCell(loc);
if (!cell.isAssigned()) {
var count = cell.getAllowedClone().count();
if (count < minCount) {
minLocation = loc;
minCount = count;
}
}
}
return minLocation;
};
Board.prototype.updateAllowed = function () {
// Called whenever the user sets a value or via auto solve
// Updates the allowed values for each cell based on existing digits
// entered in a cell's row, col or square
var cols = new Array(BoardSize);
var rows = new Array(BoardSize);
var squares = new Array(BoardSize);
// First aggregate assigned values to rows, cols, squares
var locs = Location.grid();
for (var i = 0; i < locs.length; i++) {
var loc = locs[i];
// Disallow for all cells in this row
var contains = this.getCell(loc).valueMask();
rows[loc.row] |= contains;
cols[loc.col] |= contains;
squares[loc.getSquare()] |= contains;
}
// For each cell, aggregate the values already set in that row, col and square.
// Since the aggregate is a bitmask, the bitwise inverse of that is therefore the allowed values.
this._isValid = true;
this._isSolved = true;
for (var i = 0; i < locs.length; i++) {
var loc = locs[i];
// Set allowed values
var contains = rows[loc.row] | cols[loc.col] | squares[loc.getSquare()];
var cell = this.getCell(loc);
cell.setAllowed(~contains); // set allowed values to what values are not already set in this row, col or square
cell.setAnswer(0); //clear any previous answers
// As an extra step look for "naked singles", i.e. cells that have only one allowed value, and use
// that to set the answer (note this is different from the "value" as this can only be assigned
// by the user or any auto solve functions like "accept singles"
if (!cell.isAssigned()) {
this._isSolved = false;
var mask = new AllowedValues(~contains);
var count = mask.count();
if (count == 0)
this._isValid = false;
else if (count == 1)
cell.setAnswer(mask.getSingle());
}
}
// Step 2: Look for "hidden singles".
// For each row, col, square, count number of times each digit appears.
// If any appear once then set that as the answer for that cell.
// Count in rows
for (var i = 0; i < locs.length; i++) {
var loc = locs[i];
if (!this.checkForHiddenSingles(loc, SibType.Row))// first check row sibs for a hiddne single
if (!this.checkForHiddenSingles(loc, SibType.Col))// then check cols
this.checkForHiddenSingles(loc, SibType.Square); // then check square
}
// TO DO: Add code here to detect naked/hidden doubles/triples/quads
};
Board.prototype.trySolve = function (loc, value) {// empty Location allowed
if (!loc.isEmpty())// assign a value to a location if provided
{
var cell = this.getCell(loc);
if (!cell.isAllowed(value))
throw "Internal error.";
cell.setValue(value);
}
do {
this.updateAllowed();
if (!this._isValid)
return false;
} while (this.acceptPossibles()); // keep doing deterministic answers
if (this._isSolved)
return true;
if (!this._isValid)
return false;
// No deterministic solutions, find cell with the fewest choices and try each one in turn
// until success.
var locChoice = this.findCellWithFewestChoices();
if (locChoice.isEmpty())
return false;
var cell = this.getCell(locChoice);
var allowedValues = cell._allowed.allowedValuesArray();
for (var i = 0; i < allowedValues.length; i++) {
var val = allowedValues[i];
var board = this.clone();
if (board.trySolve(locChoice, val)) {
board.copyTo(this);
return true;
}
}
return false;
};
Board.prototype.toString = function () {
var text = "";
for (var row = 0; row < BoardSize; row++)
for (var col = 0; col < BoardSize; col++) {
var val = this._digits[row][col].getValue();
text += val == 0 ? "." : String(val);
}
return text;
};
Board.prototype.setString = function (value) {
// Assumes all input is digits 1..9 or ./space
if (value.length != (BoardSize * BoardSize))
return false; //Input string is not of length 81
var n = 0;
for (var row = 0; row < BoardSize; row++)
for (var col = 0; col < BoardSize; col++) {
var ch = parseInt(value.charAt(n++)); // converts '0' to 0 etc
var cell = this._digits[row][col];
cell.setGiven(!isNaN(ch) ? ch : 0);
}
this.updateAllowed();
return true;
};
</script>
</head>
<body>
<div id='sudoku'>
<div id='banner'>
<span id='big'>Free Sudoku Solver!</span>
<span id='small'>Solves even the most difficult puzzles and provides optional hints as a training aid.</span>
</div>
<div id='main'>
<table>
<tr>
<td>
<canvas id='canvas2' width='541' height='55' title="Click here to set the currently selected digit">Canvas is not supported by this browser.</canvas>
<canvas id='canvas1' width='541' height='541'>Canvas is not supported by this browser.</canvas>
<input id='tbSerial' style='width: 538px; background-color: #faf0e6; margin-top: 10px;'/>
<br/><br/>
<span id="extraInfo" style='font-size:0.7em; color: #696969;'></span><br/>
</td>
<td style="width: 135px">
<button onclick="clearGame()" title='Clears all cells including givens. Use this initially when entering a new problem.' >Clear</button><br/>
<button onclick="loadText()" title='Loads the digits from the textbox below the board in order left to right, top to bottom. Click this after entering a problem to convert them to givens' >Load</button><br/>
<button id="btnReset" onclick="reset()" title='Clears all user entered cells. The givens are NOT cleared.'>Reset</button><br/>
<button id="btnAccept" onclick="acceptPossibles()" title='Makes all singles into values' >Accept</button><br/>
<button id="btnHint" onclick="hint()" title='Enters the answer to the currently selected cell' >Hint</button><br/>
<button id="btnUndo" onclick="undo()" title='Undoes the last user action except load, clear and reset'>Undo</button><br/>
<button id="btnSolve" onclick="solve()" title='If possible, it will solve the problem. The amount of time taken to solve is displayed below.' >Solve</button><br/><br/>
Show allowed: <input id='chbAllowed' type="checkbox" checked='yes' title='Untick this to hide allowed values'/><br/>
Show singles: <input id='chbShowSingles' type="checkbox" checked='yes' title='Untick this to hide naked and hidden singles - these are shown in red'/><br/>
<span id="message" style="width: 130; color: Red; "></span><br/>
</td>
<td class="help">
<h2>Instructions</h2>
<ul >
<li>Hit the Clear button and enter the Sudoku 'givens' manually. You can do this by
clicking on a cell, or use the keyboard arrow keys, then type the digit from '1' to '9'.
The Delete key or the '0' key will clear a cell. You can also enter a digit or clear it by clicking in the row
of digits above the board.</li>
<li>When you are finished hit the Load button. The givens will now appear in blue.</li>
<li>Hitting the Reset button will now undo all changes and take you back to the original givens.</li>
<li>The allowed digits are shown as a small light gray digit in the background of each cell. You can turn this off by unticking the 'Show allowed' option.</li>
<li>If an allowed digit is the only possible digit (these are called singles) then it is highlighted in red.
You can turn this off by unticking the 'Show singles' option.</li>
<li>Hitting the Accept button will convert singles to actual entered digits.</li>
<li>The Hint button will fill in the current selected cell with the correct digit.</li>
<li>Clicking in a cell with a digit entered will highlight the same digit anywhere alse in red.</li>
<li>Solve of course will solve the entire puzzle.</li>
<li>Undo will undo the last user action such as entering a digit or htting the Accept button.</li>
</ul>
</td>
</tr>
</table>
<script type="text/javascript" >
var CellSize = 60;
var SubCellSize = 18;
var canvas1 = document.getElementById("canvas1");
var canvas2 = document.getElementById("canvas2");
var chbAllowed = document.getElementById("chbAllowed");
var chbShowSingles = document.getElementById("chbShowSingles");
var tbSerial = document.getElementById("tbSerial");
var extraInfo = document.getElementById("extraInfo");
var board1 = new Board();
var selectRow = 0;
var selectCol = 0;
var showAllowed = true;
var showSingles = true;
var undoStack = Array();
function undo() {
var tos = undoStack.pop();
if (tos) {
board1 = tos;
updateUI();
}
}
function clearUndo() {
undoStack= Array();
}
function pushBoard() {
undoStack.push(board1.clone());
}
function checkStatus() {
extraInfo.innerHTML = "";
if (!board1._isValid)
message.innerHTML = "*Invalid*";
else if (board1._isSolved)
message.innerHTML = "*Solved*";
else
message.innerHTML = "";
}
function drawGrid() {
// Only ever called once!
var context = canvas1.getContext('2d');
context.strokeStyle = '#808080';
for (var i = 0; i <= BoardSize; i++) {
context.beginPath();
var thick = i % 3 == 0;
// Draw vertical lines
context.lineWidth = thick ? 2 : 1;
context.moveTo(i * CellSize + 0.5, 0.5);
context.lineTo(i * CellSize + 0.5, BoardSize * CellSize + 0.5);
// Draw horizontal lines
context.moveTo(0.5, i * CellSize + 0.5);
context.lineTo(BoardSize * CellSize + 0.5, i * CellSize + 0.5);
context.stroke();
}
}
function drawCells() {
var context = canvas1.getContext('2d');
context.font = "12pt Calibri"; // small text
context.textAlign = "center";
context.textBaseline = "middle";
var normalColor = "#aaaaaa";
var singleColor = "#ff143c";
// Draw background for selected cell
for (var row = 0; row < BoardSize; row++)
for (var col = 0; col < BoardSize; col++) {
// Draw background of selected cell
if (row == selectRow && col == selectCol) {
var margin = 2;
context.beginPath();
context.rect(col * CellSize + margin + 0.5, row * CellSize + margin + 0.5, CellSize - 2 * margin, CellSize - 2 * margin);
context.fillStyle = "#ffe4e1";
context.fill()
}
}
context.fillStyle = "#999999"; // text color - light
// Draw allowed values
if (showAllowed)
for (var row = 0; row < BoardSize; row++)
for (var col = 0; col < BoardSize; col++) {
var cell = board1.getCell(new Location(row, col));
if (!cell.isAssigned()) {
var allowedValues = cell._allowed.allowedValuesArray();
for (var i = 0; i < allowedValues.length; i++) {
var val = allowedValues[i];
var x = (col + 0.5) * CellSize; // center of cell for textAlign center, textBaseline middle
var y = (row + 0.5) * CellSize;
var subRow = Math.floor((val - 1) / 3) - 1;
var subCol = Math.floor((val - 1) % 3) - 1;
x += subCol * SubCellSize;
y += subRow * SubCellSize;
var hiddenSingle = allowedValues.length != 1 && val == cell.getAnswer(); // naked single would have only one allowed value
context.fillStyle = normalColor; // show hidden single in purple
if (showSingles && val == cell.getAnswer())
context.fillStyle = singleColor; // show hidden single in purple
context.fillText(val, x, y);
}
}
}
// New if a digit is selected then make all cells with the same digit foreground red
var selectCell = board1.getCell(new Location(selectRow, selectCol));
var selectValue = selectCell.getValue();
// Draw values last
context.font = "32pt Calibri";
context.textAlign = "center";
context.textBaseline = "middle";
var normalForeColor = "#191929";
var sameDigitForeColor = "#F91919";
context.fillStyle = normalForeColor; // text color - dark
for (var row = 0; row < BoardSize; row++)
for (var col = 0; col < BoardSize; col++) {
var cell = board1.getCell(new Location(row, col));
var x = (col + 0.5) * CellSize; // center of cell for textAlign center, textBaseline middle
var y = (row + 0.5) * CellSize;
var sameDigit = cell.getValue() == selectValue && selectValue != 0;
// Draw value
var value = cell.getValue();
if (value != 0) {
context.fillStyle = cell.isGiven() ? "#2200aa" : "#696969"; // show "givens" in a darker color
if (sameDigit)// then override
context.fillStyle = sameDigitForeColor; // text color - dark
context.fillText(value, x, y);
}
}
}
function drawCanvas() {
canvas1.width = canvas1.width;
drawGrid();
drawCells();
}
function updateUI() {
drawCanvas();
checkStatus();
tbSerial.value = board1.toString();
}
function readOptions() {
showAllowed = chbAllowed.checked;
showSingles = chbShowSingles.checked;
drawCanvas();
}
chbAllowed.onclick = readOptions;
chbShowSingles.onclick = readOptions;
function selectCell(row, col) {
selectRow = row;
selectCol = col;
drawCanvas();
}
function moveSelection(row, col) {
selectRow += row;
selectCol += col;
if (selectRow < 0)
selectRow = 8;
else if (selectRow > 8)
selectRow = 0;
if (selectCol < 0)
selectCol = 8;
else if (selectCol > 8)
selectCol = 0;
drawCanvas();
}
function setDigitInCell(digit) {
var cell = board1.getCell(new Location(selectRow, selectCol));
message.innerHTML = "";
if (cell.isGiven())
return;
if (digit != 0 && !cell.isAllowed(digit)) {
message.innerHTML = "Digit not allowed";
return;
}
pushBoard();
cell.setValue(digit);
board1.updateAllowed();
updateUI();
}
canvas1.onmousedown = function canvasMouseDown(ev) {
var x = ev.pageX - this.offsetLeft;
var y = ev.pageY - this.offsetTop;
var coords = this.relMouseCoords(ev);
selectCell(Math.floor(coords.y / CellSize), Math.floor(coords.x / CellSize));
}
document.onkeydown = function (ev) {
switch (ev.keyCode) {
case 37: // left arrow
moveSelection(0, -1);
break;
case 38: // up arrow
moveSelection(-1, 0);
break;
case 39: // right arrow
moveSelection(0, 1);
break;
case 40: // down arrow
moveSelection(1, 0);
break;
default:
var key = Number(ev.keyCode);
var digit = key >= 96 ? key - 96 : key - 48;// handle keypad digits as well
if (digit >= 0 && digit <= 9)
setDigitInCell(digit);
break;
}
}
function loadText() {
var ret = board1.setString(tbSerial.value);
updateUI();
if (!ret)
message.innerHTML = "String is not of length 81";
}
function clearGame() {
clearUndo();
board1.clear();
updateUI();
}
function acceptPossibles() {
pushBoard();
board1.acceptPossibles();
board1.updateAllowed();
updateUI();
}
function hint() {
// First check if we had calculated a solution, if not do so now
solution = board1.clone();
if (solution.trySolve(Location.empty, 0)) {
// There is a solution to the board from its current state
var cell = solution.getCell(new Location(selectRow, selectCol));
if (!cell.isGiven())
setDigitInCell(cell.getValue());
}
}
function reset() {
clearUndo();
board1.reset();
updateUI();
}
function solve() {
pushBoard();
var n = new Date(); // Grab new copy of date
var s = n.getTime(); // Grab current millisecond #
board1.trySolve(Location.empty, 0);
var diff = new Date().getTime() - s;
updateUI();
extraInfo.innerHTML = "Solve took " + String(diff) + " milliseconds";
}
//http://magictour.free.fr/sudoku.htm for list of hard Sudoku puzzles
// http://www.sudokuwiki.org/sudoku.htm good on-line solver accepting serial format
//board1.setString("7.8...3.....2.1...5.........4.....263...8.......1...9..9.6....4....7.5..........."); //very hard
board1.setString("7.8...3.....2.1...5..7..2...4.....263.948...7...1...9..9.6....4....7.5....5......"); // medium
updateUI();
var digCellSize = 54;
// New stuff - draw a digit selector in canvas above board
function initDigitSource() {
// Only ever called once!
var context = canvas2.getContext('2d');
context.strokeStyle = '#808080';
var SourceSize = BoardSize + 1;
for (var i = 0; i <= SourceSize; i++) {
context.beginPath();
// Draw vertical lines
context.lineWidth = 1;
context.moveTo(i * digCellSize + 0.5, 0.5);
context.lineTo(i * digCellSize + 0.5, digCellSize + 0.5);
context.stroke();
}
for (var i = 0; i <= 1; i++) {
context.beginPath();
// Draw horizontal lines
context.lineWidth = 1;
context.moveTo(0.5, i * digCellSize + 0.5);
context.lineTo(SourceSize * digCellSize + 0.5, i * digCellSize + 0.5);
context.stroke();
}
context.font = "24pt Calibri";
context.textAlign = "center";
context.textBaseline = "middle";
var normalForeColor = "#708090";
context.fillStyle = normalForeColor; // text color - dark
for (var col = 0; col < SourceSize; col++) {
var x = (col + 0.5) * digCellSize; // center of cell for textAlign center, textBaseline middle
var y = 0.5 * digCellSize;
var value = col < 9 ? col + 1 : "Del";
context.fillStyle = normalForeColor; // show "givens" in a darker color
context.fillText(value, x, y);
}
}
initDigitSource();
canvas2.onmousedown = function canvasMouseDown(ev) {
var x = ev.pageX - this.offsetLeft;
var y = ev.pageY - this.offsetTop;
var coords = this.relMouseCoords(ev);
var dig = Math.floor(coords.x / digCellSize) + 1;
if (dig == 10)
dig = 0;
setDigitInCell(dig);
}
</script>
</div>
</div>
</body>
</html>
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