public (List <SudokuCell>, List <int>, List <int>, List <int>) GrabSubgroup(int targetNumber)
{
List <SudokuCell> possibleCells = XGrab(targetNumber); //the list of cells with targetNumber as possibility
List <int> retrievedRowIndices = SudokuCellExtensions.DeriveRowNums(possibleCells); //the rows of the cells with targetNumber as possibility
List <int> retrievedColIndices = SudokuCellExtensions.DeriveColNums(possibleCells); //the columns of the cells with targetNumber as possibility
List <int> retrievedSGIndices = SudokuCellExtensions.DeriveSGNums(possibleCells); //the subgrids of the cells with targetNumber as possibility
return(possibleCells, retrievedRowIndices, retrievedColIndices, retrievedSGIndices);
}
private static SudokuCell[,] LoadDataFromFile(string path)
{
using var streamReader = new StreamReader(path);
var data = streamReader.ReadToEnd();
var byteData = Encoding.UTF8.GetBytes(data);
try
{
return(SudokuCellExtensions.ConvertToSudokuCellArray(byteData));
}
catch
{
return(null);
}
}
public void SubgroupExculsion(int targetNum)
{
(List <SudokuCell> candidateCells, List <int> rowInds, List <int> colInds, List <int> sgInds) = GrabSubgroup(targetNum);
Dictionary <int, List <SudokuCell> > rowPossCs = new Dictionary <int, List <SudokuCell> >();
Dictionary <int, List <SudokuCell> > colPossCs = new Dictionary <int, List <SudokuCell> >();
Dictionary <int, List <SudokuCell> > sgPossCs = new Dictionary <int, List <SudokuCell> >();
Dictionary <SGUnitIntersectKey, List <SudokuCell> > sgIntersects = new Dictionary <SGUnitIntersectKey, List <SudokuCell> >(); //an empty dictionary to store the SGUnitIntersectKey, List<SudokuCell> pairs
foreach (int rowInd in rowInds) //for each row in the returned list of row indices
{
var rQuery = candidateCells.Select(x => x).Where(y => y.rowNumber == rowInd); //select all cells in candidateCells where the rowNumber matches the current row index
rowPossCs[rowInd] = rQuery.ToList(); //store the list of cells in the appropriate row number in dictionary.
}
foreach (int colInd in colInds)
{
var cQuery = candidateCells.Select(x => x).Where(y => y.colNumber == colInd);
colPossCs[colInd] = cQuery.ToList();
}
foreach (int sgInd in sgInds)
{
var sgQuery = candidateCells.Select(x => x).Where(y => y.sgNumber == sgInd);
sgPossCs[sgInd] = sgQuery.ToList();
List <int> sgRs = SudokuCellExtensions.DeriveRowIndicesFromSG(sgInd);
List <int> sgCs = SudokuCellExtensions.DeriveColIndicesFromSG(sgInd);
foreach (int key in rowPossCs.Keys)
{
if (sgRs.Contains(key))
{
SGUnitIntersectKey rca = new SGUnitIntersectKey(sgInd, UnitType.row, key);
List <SudokuCell> intersectVals = GetSGIntersect(sgPossCs[sgInd], rowPossCs[key]);
if (intersectVals != null)
{
if (intersectVals.Count > 1)
{
sgIntersects[rca] = intersectVals;
}
}
}
}
foreach (int key in colPossCs.Keys)
{
if (sgCs.Contains(key))
{
SGUnitIntersectKey cca = new SGUnitIntersectKey(sgInd, UnitType.column, key);
List <SudokuCell> intersectVals = GetSGIntersect(sgPossCs[sgInd], colPossCs[key]);
if (intersectVals != null)
{
if (intersectVals.Count > 1)
{
sgIntersects[cca] = intersectVals;
}
}
}
}
}
List <SGUnitIntersectKey> targetedSubgroupKeys = sgIntersects.Keys.ToList();
foreach (SGUnitIntersectKey sgIK in targetedSubgroupKeys)
{
List <SudokuCell> openSGs = candidateCells.Select(x => x).Where(y => y.sgNumber == sgIK.sgValue).ToList();
foreach (SudokuCell openSGCell in openSGs)
{
if (!sgIntersects[sgIK].Contains(openSGCell))
{
sudoku.discardedValuesTable.AddDiscardedValue(openSGCell, targetNum);
}
}
}
}
