public PuzzleSet([NotNull] PuzzleSet other)
{
if (other == null)
{
throw new ArgumentNullException(nameof(other));
}
MaxValue = other.MaxValue;
Bits = new BitArray(other.Bits);
}
/// <summary>
/// Analyzes the puzzle's values to determine its current status.
/// </summary>
/// <param name="puzzle"></param>
/// <returns>The state of the puzzle.</returns>
public static PuzzleStatus GetPuzzleStatus(this Puzzle puzzle)
{
if (puzzle == null)
{
throw new ArgumentNullException(nameof(puzzle));
}
// buffer for tracking used numbers in a ror, column or box
var puzzleSize = puzzle.Size.ToInt32();
PuzzleSet numbersUsed;
// Make sure every column contains the right numbers. It's ok if a column has holes
// as long as those cells have possibilities, in which case it's a puzzle in progress.
// However, two numbers can't be used in the same column, even if there are holes.
foreach (var row in puzzle.ByRow())
{
numbersUsed = new PuzzleSet(puzzle.Size);
foreach (var cell in row)
{
if (cell.Value.HasValue)
{
var value = cell.Value.Value;
if (numbersUsed.Contains(value))
{
return(PuzzleStatus.Invalid);
}
numbersUsed.Add(value);
}
}
}
// Same for columns
foreach (var col in puzzle.ByCol())
{
numbersUsed = new PuzzleSet(puzzle.Size);
foreach (var cell in col)
{
if (cell.Value.HasValue)
{
var value = cell.Value.Value;
if (numbersUsed.Contains(value))
{
return(PuzzleStatus.Invalid);
}
numbersUsed.Add(value);
}
}
}
// Same for boxes
foreach (var box in puzzle.ByBox())
{
numbersUsed = new PuzzleSet(puzzle.Size);
foreach (var cell in box)
{
if (cell.Value.HasValue)
{
var value = cell.Value.Value;
if (numbersUsed.Contains(value))
{
return(PuzzleStatus.Invalid);
}
numbersUsed.Add(value);
}
}
}
// Now figure out if this is a solved puzzle or a work in progress
// based on if there are any holes
for (var row = 0; row < puzzleSize; row++)
{
for (var col = 0; col < puzzleSize; col++)
{
var coord = new PuzzleCoordinate(row, col);
if (!puzzle[coord].HasValue)
{
return(PuzzleStatus.InProgress);
}
}
}
// If we made it this far, this state is a valid solution! Woo hoo!
return(PuzzleStatus.Solved);
}