private static IEnumerable <int?[]> generateCombinations(bool isCol, int rowCol, int[] clue, IEnumerable <UniquenessConstraint> furtherRestrictions, int gridWidth, int gridHeight, int minValue, int maxValue)
{
var combinations = new List <int?[]>();
var affectedCenterCells = Enumerable.Range(0, isCol ? gridHeight : gridWidth).Select(ix => isCol ? rowCol + gridWidth * ix : ix + gridWidth * rowCol).ToArray();
bool combinationAcceptable(int?[] combination)
{
if (furtherRestrictions == null)
{
return(true);
}
foreach (var uniq in furtherRestrictions)
{
for (var i = 0; i < uniq.AffectedCells.Length; i++)
{
if (combination[uniq.AffectedCells[i]] != null)
{
for (var j = i + 1; j < uniq.AffectedCells.Length; j++)
{
if (combination[uniq.AffectedCells[j]] == combination[uniq.AffectedCells[i]])
{
return(false);
}
}
}
}
}
return(true);
}
switch (clue.Length)
{
case 0:
return(Enumerable.Empty <int?[]>());
case 1:
{
for (var i1 = 0; i1 < affectedCenterCells.Length; i1++)
{
var comb = new int?[gridWidth * gridHeight];
var neigh1 = PuzzleUtil.Orthogonal(affectedCenterCells[i1], gridWidth, gridHeight).ToArray();
foreach (var numbers in PuzzleUtil.Combinations(minValue, maxValue, neigh1.Length, allowDuplicates: true).Where(c => c.Sum() == clue[0]))
{
for (var i = 0; i < neigh1.Length; i++)
{
comb[neigh1[i]] = numbers[i];
}
if (combinationAcceptable(comb))
{
combinations.Add((int?[])comb.Clone());
}
}
}
break;
}
case 2:
{
for (var i1 = 0; i1 < affectedCenterCells.Length; i1++)
{
var comb = new int?[gridWidth * gridHeight];
var neigh1 = PuzzleUtil.Orthogonal(affectedCenterCells[i1], gridWidth, gridHeight).ToArray();
foreach (var numbers in PuzzleUtil.Combinations(minValue, maxValue, neigh1.Length, allowDuplicates: true).Where(c => c.Sum() == clue[0]))
{
for (var i = 0; i < neigh1.Length; i++)
{
comb[neigh1[i]] = numbers[i];
}
if (!combinationAcceptable(comb))
{
continue;
}
for (var i2 = i1 + 1; i2 < affectedCenterCells.Length; i2++)
{
var neigh2 = PuzzleUtil.Orthogonal(affectedCenterCells[i2], gridWidth, gridHeight).ToArray();
foreach (var numbers2 in PuzzleUtil.Combinations(minValue, maxValue, neigh2.Length, allowDuplicates: true).Where(c => c.Sum() == clue[1]))
{
var comb2 = (int?[])comb.Clone();
for (var i = 0; i < neigh2.Length; i++)
{
if (comb2[neigh2[i]] != null && comb2[neigh2[i]] != numbers2[i])
{
goto busted2;
}
comb2[neigh2[i]] = numbers2[i];
}
if (combinationAcceptable(comb2))
{
combinations.Add(comb2);
}
}
busted2 :;
}
}
}
break;
}
default:
throw new NotImplementedException("NeighborSumConstraint currently only supports up to 2 numbers per clue.");
}
return(combinations);
}
private bool isUnique(int[] rowSums, int[] rowVoltorbs, int[] colSums, int[] colVoltorbs, int[] givenCells)
{
var puzzle = new Puzzle(25, 0, 3);
for (var i = 0; i < 5; i++)
{
puzzle.AddConstraint(new CombinationsConstraint(Enumerable.Range(0, 5).Select(j => j + 5 * i), PuzzleUtil.Combinations(0, 3, 5, true).Where(c => c.Sum() == rowSums[i] && c.Count(v => v == 0) == rowVoltorbs[i])));
puzzle.AddConstraint(new CombinationsConstraint(Enumerable.Range(0, 5).Select(j => i + 5 * j), PuzzleUtil.Combinations(0, 3, 5, true).Where(c => c.Sum() == colSums[i] && c.Count(v => v == 0) == colVoltorbs[i])));
}
for (var gcIx = 0; gcIx < givenCells.Length; gcIx++)
{
puzzle.AddConstraint(new GivenConstraint(givenCells[gcIx], 0));
}
bool[] voltorbs = null;
foreach (var solution in puzzle.Solve())
{
if (voltorbs == null)
{
voltorbs = solution.Select(v => v == 0).ToArray();
}
else
{
for (var i = 0; i < solution.Length; i++)
{
if ((solution[i] == 0) != voltorbs[i])
{
return(false);
}
}
}
}
return(true);
}