public bool VerifyColumn(int columnNumber)
{
CellCoordinate cell = new CellCoordinate(0, columnNumber);
Del handler = cell.MoveToNextCellInColumn;
return(Verify(handler));
}
public bool FillBoard(CellCoordinate cell)
{
if (IsCellEmpty(cell))
{
iterations++;
foreach (int value in Enumerable.Range(1, 9))
{
if (!TrySetCell(cell, value))
{
continue;
}
Print();
if (FillBoard(cell))
{
return(true);
}
}
ClearCell(cell);
return(false);
}
if (cell.MoveToNextCellInGrid())
{
return(FillBoard(cell));
}
return(true);
}
public bool VerifyRow(int rowNumber)
{
CellCoordinate cell = new CellCoordinate(rowNumber, 0);
Del handler = cell.MoveToNextCellInRow;
return(Verify(handler));
}
public bool VerifyBlock(int blockNumber)
{
int rowOffset = (blockNumber / 3) * 3;
int columnOffset = (blockNumber % 3) * 3;
CellCoordinate cell = new CellCoordinate(rowOffset, columnOffset);
Del handler = cell.MoveToNextCellInBlock;
return(Verify(handler));
}
public void DeleteRandomCell()
{
CellCoordinate cell = new CellCoordinate();
do
{
cell.Randomize();
} while (IsCellEmpty(cell));
ClearCell(cell);
}
public bool IncreaseCellValue(CellCoordinate cell)
{
if (board[cell.row, cell.column] < 9)
{
board[cell.row, cell.column]++;
return(true);
}
board[cell.row, cell.column] = 0;
return(false);
}
public bool TrySetCell(CellCoordinate cell, int value)
{
SetCell(cell, value);
return(VerifyBoard());
}
public bool IsCellEmpty(CellCoordinate cell)
{
return(board[cell.row, cell.column] == 0);
}
public void ClearCell(CellCoordinate cell)
{
board[cell.row, cell.column] = 0;
}
public int GetCell(CellCoordinate cell)
{
return(board[cell.row, cell.column]);
}
public void SetCell(CellCoordinate cell, int value)
{
board[cell.row, cell.column] = value;
}
public void Solve()
{
CellCoordinate cell = new CellCoordinate();
FillBoard(cell);
}