/// <summary>Initializes a lookup to map each square to its corresponding regions.</summary>
private void InitializeLookup()
{
for (var index = 0; index < Lookup.Length; index++)
{
Lookup[index] = new SudokuRegions();
}
foreach (var region in Regions)
{
foreach (var square in region)
{
Lookup[square].Add(region);
}
}
}
/// <summary>Constructs a Sudoku puzzle based on its size.</summary>
/// <param name="size">
/// The size of a single square.
/// </param>
protected SudokuPuzzle(int size)
{
this.Size2 = size * size;
Grid = new int[Size2, Size2];
Regions = new SudokuRegions();
Lookup = new SudokuRegions[Size2 * Size2];
InitializeGrid(Size2);
InitializeRowRegions(Size2);
InitializeColumnRegions(Size2);
InitializeSubSquareRegions(size);
InitializeLookup();
InitializeIntersected();
}
/// <summary>Gets the Singleton instance of 3x3 puzzle.</summary>
private SudokuPuzzle()
{
const int size = 3;
Size2 = size * size;
Grid = new int[Size2, Size2];
Regions = new SudokuRegions();
Lookup = new SudokuRegions[Size2 * Size2];
InitializeGrid(Size2);
InitializeRowRegions(Size2);
InitializeColumnRegions(Size2);
InitializeSubSquareRegions(size);
InitializeLookup();
InitializeIntersected();
}
/// <summary>Initializes a lookup to map each square to its corresponding regions.</summary>
protected void InitializeLookup()
{
for (var index = 0; index < Lookup.Length; index++)
{
Lookup[index] = new SudokuRegions();
}
foreach (var region in Regions)
{
foreach (var square in region)
{
Lookup[square].Add(region);
}
}
}
/// <summary>Creates a Sudoku region.</summary>
public SudokuRegion(SudokuRegionType type)
{
RegionType = type;
Intersected = new SudokuRegions();
}