//copy constructor
public PossibilitySet(PossibilitySet toCopy)
{
foreach (HashSet <int> set in toCopy)
{
Add(new HashSet <int>(set));
}
}
//Make this instance a deep copy of toCopy
private void copy(gridSquare toCopy)
{
this.x = toCopy.x;
this.y = toCopy.y;
this.knownValue = toCopy.knownValue;
for (int i = 1; i <= 9; ++i)
{
this.possibilities[i] = toCopy.possibilities[i];
}
this.possList = new List <int>(toCopy.possList);
this.solveType = toCopy.solveType;
this.setList = new PossibilitySet(toCopy.setList);
}
//initialize/return to freshly constructed state
public void setToInitialState()
{
knownValue = 0;
for (int i = 1; i <= 9; ++i)
{
possibilities[i] = true;
}
possList = new List <int> {
1, 2, 3, 4, 5, 6, 7, 8, 9
};
setList = new PossibilitySet(new HashSet <int>(possList), maxSetLength);
solveType = SudokuGrid.SolveType.Unsolved;
}
//scan for and use aligned matched sets to eliminate other possibilities
private bool matchedSetEliminationScan()
{
bool madeChanges = false;
//scan for sets in box, in col, in row
//check by each section type
foreach (iterateBy iterType in Enum.GetValues(typeof(iterateBy)))
{
//for each section:
for (int s = 0; s < 9; s++)
{
if (unsolvedValues[(int)iterType, s].Count == 0)
{
continue; //section already completely solved
}
PossibilitySet sectionPossibilities = new PossibilitySet(unsolvedValues[(int)iterType, s], 8);
foreach (HashSet <int> set in sectionPossibilities)
{
HashSet <int> matchIndices = new HashSet <int>();
//for each element in section
for (int e = 0; e < 9; e++)
{
bool match = true;
for (int i = 1; i <= 9; i++)
{
if (!set.Contains(i) && iterCoords(iterType, s, e).isPossible(i))
{
match = false;
break;
}
}
if (match)
{
matchIndices.Add(e);
}
}
if (matchIndices.Count == set.Count)
{
bool tempMadeChanges = false;
//values in set can ONLY be in squares that contain only values in set
//so eliminate set values all other places in section
for (int eE = 0; eE < 9; eE++)
{
if (matchIndices.Contains(eE))
{
continue;
}
foreach (int i in set)
{
tempMadeChanges |= iterCoords(iterType, s, eE).eliminate(i);
}
}
if (tempMadeChanges)
{
madeChanges = true;
}
}
}
}
}
return(madeChanges);
}
