private void FindTuple(MutablePuzzle puzzle, RegionQueue regions, Region region, SudokuValues placedDigits)
{
var combinations = Helpers.GetCombinationIndices(Puzzle.LineLength, _size);
for (int i = 0; i < combinations.Length; i++)
{
var comb = combinations[i];
if (placedDigits.HasAnyOptions(comb))
{
// skip any tuples that include placed digits
continue;
}
var positions = region.GetPositions(comb);
if (positions.GetOptionCount() != _size)
{
// these digits are placeable in more than tupleSize spots, so not hidden tuple
continue;
}
// we found a hidden tuple!
var options = ArrayPool <int> .Shared.Rent(Puzzle.LineLength);
var count = positions.CopyIndices(options);
var opposite = comb.Invert();
var anyChanged = false;
for (var index = 0; index < count; index++)
{
var cell = region[options[index]];
if (!cell.IsSingle && cell.HasAnyOptions(opposite))
{
var update = region.RemoveOptions(options[index], opposite);
puzzle.RemoveOptions(update);
anyChanged = true;
regions.Enqueue(RegionType.Row, update.Coordinate.Row);
regions.Enqueue(RegionType.Column, update.Coordinate.Column);
regions.Enqueue(RegionType.Box, update.Coordinate.Box);
}
}
ArrayPool <int> .Shared.Return(options);
if (anyChanged)
{
#if DEBUG
Program.Debugger.AddAction($"Hidden {comb} tuple in {region}");
#endif
return;
}
}
}
private void FindTuple(MutablePuzzle puzzle, RegionQueue regions, Region region, SudokuValues placedDigits)
{
var combinations = Helpers.GetCombinationIndices(Puzzle.LineLength, _size);
for (int j = 0; j < combinations.Length; j++)
{
var comb = combinations[j];
if (placedDigits.HasAnyOptions(comb))
{
// skip any tuples that include placed digits
continue;
}
var indices = ArrayPool <int> .Shared.Rent(_size);
var count = comb.CopyIndices(indices);
var possibleValues = SudokuValues.None;
for (int i = 0; i < count; i++)
{
var cell = region[indices[i]];
possibleValues = possibleValues.AddOptions(cell);
}
ArrayPool <int> .Shared.Return(indices);
var optionsCount = possibleValues.GetOptionCount();
if (optionsCount == _size)
{
// we found a tuple!
for (var i = 0; i < Puzzle.LineLength; i++)
{
var otherCell = region[i];
if (otherCell.IsSingle)
{
continue;
}
if (!otherCell.HasAnyOptions(possibleValues))
{
continue;
}
if (comb.HasAnyOptions(SudokuValues.FromIndex(i)))
{
continue;
}
var newCell = region.RemoveOptions(i, possibleValues);
puzzle.RemoveOptions(newCell);
regions.Enqueue(RegionType.Row, newCell.Coordinate.Row);
regions.Enqueue(RegionType.Column, newCell.Coordinate.Column);
regions.Enqueue(RegionType.Box, newCell.Coordinate.Box);
#if DEBUG
Program.Debugger.AddAction($"{possibleValues} tuple in {region}.");
#endif
}
}
}
}
