void InitMatrix()
{
// counting the number of source nodes and creating field of them
field = new NodeItem[fieldSource.GetLength(0), fieldSource.GetLength(1)];
// counting nodes
int nodeItemCount = 0;
for (int x = 0; x < fieldSource.GetLength(0); x++)
{
for (int y = 0; y < fieldSource.GetLength(1); y++)
{
if (fieldSource[x, y] == 1)
{
NodeItem item = new NodeItem()
{
x = x, y = y
};
field[x, y] = item;
nodeItemCount++;
}
}
}
dancingLinks.InitHeaders(nodeItemCount + figureSet.FigureCount);
// assigning a node to every column header just to make it distinct
ExactCover.Node header = dancingLinks.rootHeader.right;
for (int x = 0; x < field.GetLength(0); x++)
{
for (int y = 0; y < field.GetLength(1); y++)
{
if (field[x, y] != null)
{
header.nodedata = field[x, y];
header = header.right;
}
}
}
// assigning a node containing figure id to header columns
figureNodes = new NodeFigure[figureSet.FigureCount];
for (int i = 0; i < figureSet.FigureCount; i++)
{
var newNode = new NodeFigure()
{
figureId = i
};
header.nodedata = newNode;
// all figure headers are optional
((ExactCover.ColumnHeader)header).optional = true;
header = header.right;
figureNodes[i] = newNode;
}
}
public bool Solve()
{
// matrix doesn't have any rows
if (nLines == 0)
{
return(false);
}
bool result = dancingLinks.Solve();
if (result)
{
// transforming the result to the form of array of chars that can be easily output to screen
Solution = new char[field.GetLength(0), field.GetLength(1)];
// filling all with spaces
for (int x = 0; x < Solution.GetLength(0); x++)
{
for (int y = 0; y < Solution.GetLength(1); y++)
{
Solution[x, y] = ' ';
}
}
foreach (ExactCover.Node figure in dancingLinks.Solution)
{
// finding figure id (type)
int figureId = 0;
ExactCover.Node node = figure;
do
{
if (node.nodedata.GetType() == typeof(NodeFigure))
{
NodeFigure figureType = (NodeFigure)node.nodedata;
if (figureType != null)
{
figureId = figureType.figureId;
break;
}
}
node = node.right;
} while (node != figure);
// placing all nodes in the char[,] array
node = figure;
do
{
if (node.nodedata.GetType() == typeof(NodeItem))
{
NodeItem item = (NodeItem)node.nodedata;
if (item != null)
{
Solution[item.x, item.y] = (char)((int)'A' + figureId);
}
}
node = node.right;
} while (node != figure);
}
}
return(result);
}
void AddFigureToMatrix(long[] figure, int figureId, int fCol, int fRow)
{
int nFigureRows = figure.Length;
ArrayList newRow = new ArrayList();
// adding all five field nodes
for (int row = 0; row < nFigureRows; row++)
{
for (int col = 0; col < 5; col++)
{
if ((figure[row] & (1 << col)) != 0)
{
// add new node to header
NodeItem item = field[row + fRow, col + fCol];
foreach (ExactCover.ColumnHeader colHeader in dancingLinks.columnHeaders)
{
if (colHeader.nodedata == item)
{
ExactCover.Node newNode = new ExactCover.Node()
{
nodedata = item
};
colHeader.Add(newNode);
newRow.Add(newNode);
break;
}
}
}
}
}
// adding figure node
NodeFigure nodeFigure = Array.Find <NodeFigure>(figureNodes, (fNode) => (fNode.figureId == figureId));
foreach (ExactCover.ColumnHeader colHeader in dancingLinks.columnHeaders)
{
if (colHeader.nodedata == nodeFigure)
{
ExactCover.Node newNode = new ExactCover.Node()
{
nodedata = nodeFigure
};
colHeader.Add(newNode);
newRow.Add(newNode);
break;
}
}
// establishing links between nodes in a row through left and right pointers
ExactCover.Node startNode = null;
ExactCover.Node previousNode = null;
for (ExactCover.Node node = dancingLinks.rootHeader.right; node != dancingLinks.rootHeader; node = node.right)
{
foreach (ExactCover.Node rowNode in newRow)
{
if ((startNode == null) && (node.nodedata == rowNode.nodedata))
{
startNode = rowNode;
previousNode = rowNode;
continue;
}
if ((startNode != null) && (node.nodedata == rowNode.nodedata))
{
ExactCover.Node currentNode = rowNode;
previousNode.right = currentNode;
currentNode.left = previousNode;
previousNode = currentNode;
}
}
}
previousNode.right = startNode;
startNode.left = previousNode;
}
void AddFigureToMatrix(long[] figure, int figureId, int fCol, int fRow)
{
int nFigureRows = figure.Length;
ArrayList newRow = new ArrayList();
// adding all five field nodes
for (int row = 0; row < nFigureRows; row++) {
for (int col = 0; col < 5; col++) {
if ( (figure[row] & (1 << col)) != 0) {
// add new node to header
NodeItem item = field[row + fRow, col + fCol];
foreach (ExactCover.ColumnHeader colHeader in dancingLinks.columnHeaders) {
if (colHeader.nodedata == item) {
ExactCover.Node newNode = new ExactCover.Node() { nodedata = item };
colHeader.Add(newNode);
newRow.Add(newNode);
break;
}
}
}
}
}
// adding figure node
NodeFigure nodeFigure = Array.Find<NodeFigure>(figureNodes, (fNode) => ( fNode.figureId == figureId ) );
foreach(ExactCover.ColumnHeader colHeader in dancingLinks.columnHeaders) {
if (colHeader.nodedata == nodeFigure) {
ExactCover.Node newNode = new ExactCover.Node() { nodedata = nodeFigure };
colHeader.Add(newNode);
newRow.Add(newNode);
break;
}
}
// establishing links between nodes in a row through left and right pointers
ExactCover.Node startNode = null;
ExactCover.Node previousNode = null;
for (ExactCover.Node node = dancingLinks.rootHeader.right; node != dancingLinks.rootHeader; node = node.right) {
foreach (ExactCover.Node rowNode in newRow) {
if ((startNode == null) && (node.nodedata == rowNode.nodedata)) {
startNode = rowNode;
previousNode = rowNode;
continue;
}
if ((startNode != null) && (node.nodedata == rowNode.nodedata)) {
ExactCover.Node currentNode = rowNode;
previousNode.right = currentNode;
currentNode.left = previousNode;
previousNode = currentNode;
}
}
}
previousNode.right = startNode;
startNode.left = previousNode;
}
