private bool SetCellPossibilityToFalse(SudokuCell cell, int number)
{
if (cell.Number > 0) return false;
if (cell.PossibleNumbers[number])
{
cell.PossibleNumbers[number] = false;
bool isSolved = cell.IsSolved();
if (!CheckValid())
{
int thisIsTheSpotToCheck = 10;
}
if (isSolved) SolvedCellCleanup(cell);
return isSolved;
}
return false;
}
private void SolvedCellCleanup(SudokuCell solvedCell)
{
string values = solvedCell.Possibilities;
List<SudokuCell> horiz = GetCellGroupingFor(solvedCell, CellGroupingType.Horizontal);
CleanOtherCells(horiz, values);
List<SudokuCell> verts = GetCellGroupingFor(solvedCell, CellGroupingType.Vertical);
CleanOtherCells(verts, values);
List<SudokuCell> sqrs = GetCellGroupingFor(solvedCell, CellGroupingType.Square);
CleanOtherCells(sqrs, values);
}
private void Print(SudokuCell[,] data)
{
for (int row = 0; row < 9; row++)
{
for (int col = 0; col < 9; col++)
{
string print;
if (data[col, row].Number == 0)
{
print = "- ";
}
else
{
print = String.Format("{0} ", data[col, row].Number);
}
Console.Write(print);
}
Console.WriteLine();
}
Console.WriteLine("\t Number left: {0}", CountNumberLeft(data));
}
private void PrintBig(SudokuCell[,] data)
{
string longdash = new string('─', 11);
Console.WriteLine("┌{0}┬{0}┬{0}┐", "───┬───┬───");
for (int row = 0; row < 9; row++)
{
for (int subrow = 1; subrow <= 3; subrow++)
{
Console.Write("│");
for (int col = 0; col < 9; col++)
{
for (int possibleNbr = (1 + (subrow - 1) * 3); possibleNbr <= (subrow * 3); possibleNbr++)
{
if (data[col, row].Number == 0)
Console.Write((data[col, row].PossibleNumbers[possibleNbr]) ? (possibleNbr).ToString() : " ");
else
Console.Write(data[col, row].Number.ToString());
}
Console.Write("│");
}
Console.WriteLine();
//if (subrow < 3)
// Console.WriteLine("│{0}│{0}│{0}│", longdash);
}
if ((row + 1) % 3 == 0)
{
if (row < 8)
Console.WriteLine("├{0}┼{0}┼{0}┤", "───┼───┼───");
}
else
{
Console.WriteLine("├{0}┼{0}┼{0}┤", "───┼───┼───");
}
}
Console.WriteLine("└{0}┴{0}┴{0}┘", "───┴───┴───");
Console.WriteLine();
}
private void LoadStringData(string raw)
{
for (int x = 0; x < 9; x++)
{
for (int y = 0; y < 9; y++)
{
int idx = y * 9 + x;
originalData[x, y] = new SudokuCell(raw.Substring(idx, 1), x, y);
}
}
}
private List<SudokuCell> GetCellGroupingFor(SudokuCell cell, CellGroupingType type)
{
int col = cell.Col;
int row = cell.Row;
List<SudokuCell> cells = new List<SudokuCell>();
switch (type)
{
case CellGroupingType.Horizontal:
for (int i = 0; i < 9; i++)
{
cells.Add(solvedData[i, row]);
}
break;
case CellGroupingType.Vertical:
for (int i = 0; i < 9; i++)
{
cells.Add(solvedData[col, i]);
}
break;
case CellGroupingType.Square:
int gridCol = col / 3;
int gridRow = row / 3;
int gridX = 3 * gridCol;
int gridY = 3 * gridRow;
for (int x = gridX; x - gridX < 3; x++)
{
for (int y = gridY; y - gridY < 3; y++)
{
cells.Add(solvedData[x, y]);
}
}
break;
}
return cells;
}
private int CountNumberLeft(SudokuCell[,] data)
{
int numLeft = 0;
for (int row = 0; row < 9; row++)
{
for (int col = 0; col < 9; col++)
{
if (data[col, row].Number == 0)
{
numLeft++;
}
}
}
return numLeft;
}
public bool SolveSudoku(int thisProblemNumber, bool debug)
{
PrintBig(originalData);
// we'll start at the beginning and
// use solvedData as our work area.
for (int x = 0; x < 9; x++)
{
for (int y = 0; y < 9; y++)
{
solvedData[x, y] = new SudokuCell(originalData[x, y].Number, x, y);
}
}
int round = 1;
int thisRoundNumLeft = -1;
int lastRoundNumLeft = -1;
do
{
//Check Horizontals
for (int row = 0; row < 9; row++)
{
// get list of cells for this column
List<SudokuCell> cells = GetCellGroupingFor(solvedData[0, row], CellGroupingType.Horizontal);
// apply logic to this independant grouping
NarrowDownIndependantCellGrouping(cells, CellGroupingType.Horizontal);
}
//Check Verticals
for (int col = 0; col < 9; col++)
{
// get list of cells for this column
List<SudokuCell> cells = GetCellGroupingFor(solvedData[col, 0], CellGroupingType.Vertical);
// apply logic to this independant grouping
NarrowDownIndependantCellGrouping(cells, CellGroupingType.Vertical);
}
// Check Square Groups
for (int gridRow = 0; gridRow < 3; gridRow++)
{
for (int gridCol = 0; gridCol < 3; gridCol++)
{
// create a list of cells for this group
List<SudokuCell> cells = GetCellGroupingFor(solvedData[gridCol * 3, gridRow * 3], CellGroupingType.Square);
// apply logic to this independant grouping
NarrowDownIndependantCellGrouping(cells, CellGroupingType.Square);
}
}
// **** NOTE ****
// SEE: http://www.sudokuessentials.com/sudoku_tips.html
// **** NOTE ****
if (debug)
{
Console.WriteLine("After Round {0}:", round);
PrintBig(solvedData);
}
thisRoundNumLeft = CountNumberLeft(solvedData);
round++;
if (thisRoundNumLeft == lastRoundNumLeft)
{
Console.WriteLine("!!!!!!!!!!!!!!!!! Not making any headway on {0} !!!!!!!!", thisProblemNumber);
if (debug) PrintBig(solvedData);
if (CheckValid())
{
bool guessedCorrect = false;
// now make guesses and solve each guess
for (int row = 0; row < 10; row++)
{
if (guessedCorrect) break;
for (int col = 0; col < 10; col++)
{
if (guessedCorrect) break;
if (solvedData[col, row].Number == 0)
{
for (int i = 1; i < 10; i++)
{
string theseUsed = solvedData[col, row].Possibilities;
if (theseUsed.Substring(i, 1) != "-")
{
Sudoku newPuzzle = new Sudoku(solvedData);
newPuzzle.originalData[col, row].Number = i;
guessedCorrect = newPuzzle.SolveSudoku(thisProblemNumber, debug);
if (guessedCorrect)
{
solvedData = newPuzzle.solvedData;
}
}
if (guessedCorrect) break;
}
}
}
}
}
break;
}
lastRoundNumLeft = thisRoundNumLeft;
} while (!IsCompletelySolved);
if (!debug) PrintBig(solvedData);
return CheckValid();
}
public Sudoku(SudokuCell[,] original_data)
{
for (int x = 0; x < 9; x++)
{
for (int y = 0; y < 9; y++)
{
int idx = y * 9 + x;
originalData[x, y] = new SudokuCell(original_data[x, y].Number, x, y);
}
}
}