private uint DoExtraSearch(SolverParam param)
{
uint walk = 0;
Random rnd = new Random();
Stroke stroke = puzzleData;
int nbVerses = stroke.Verses.Count;
Stack <int> proposal = new Stack <int>(),
candidate = new Stack <int>(Enumerable.Reverse(Enumerable.Range(0, nbVerses)));
List <Verse> result = new List <Verse>();
List <int>[] visited = new List <int> [nbVerses];
for (int vv = 0; vv < nbVerses; ++vv)
{
visited[vv] = new List <int>();
}
while (candidate.Count > 0)
{
int curIdx = candidate.Pop();
List <int> curVisisted = visited[curIdx];
// Existing verses construct the constraints.
List <int[]> constraints = stroke.Anchors;
int requiredLength = stroke.Verses[curIdx].Length;
bool foundOne = true;
// Look up in the data.
int s = 0;
Verse v = new Verse();
if (stroke.Verses[curIdx].Content[0] != 0xFF)
{
// Fixed verse.
s = dictDataMatrices[requiredLength].FindIndex(
(x) =>
{
bool found = true;
for (int i = 0; i < requiredLength; ++i)
{
if (x[i] != stroke.Verses[curIdx].Content[i])
{
found = false;
break;
}
}
return(found);
});
}
else
{
// Variant verse.
for (s = 0; s < dictDataMatrices[requiredLength].Count; ++s)
{
if (param.MaxStep > 0 && walk > param.MaxStep)
{
return(walk);
}
// Prevent replicate verses.
foundOne = true;
if (usedIndices[requiredLength].Contains(s) || curVisisted.Contains(s))
{
foundOne = false;
continue;
}
++walk;
ushort[] content = dictDataMatrices[requiredLength][s];
foreach (int[] a in constraints)
{
if (a[4] == 0xFF)
{
// Variant anchor.
if (proposal.Contains(a[0]) && curIdx == a[2])
{
ushort trait = content[a[3]],
check = result[a[0]].Content[a[1]];
if (trait != check)
{
foundOne = false;
break;
}
}
}
else
{
// Fixed anchor.
if (a[0] == curIdx && content[a[1]] != a[4])
{
foundOne = false;
break;
}
if (a[2] == curIdx && content[a[3]] != a[4])
{
foundOne = false;
break;
}
}
// For each search, check the constraints.
}
if (foundOne)
{
break;
}
}
}
if (foundOne)
{
// Next step.
curVisisted.Add(s);
v.Length = requiredLength;
v.Content = dictDataMatrices[requiredLength][s];
result.Add(v);
proposal.Push(curIdx);
}
else
{
// Trace back.
curVisisted.Clear();
result.RemoveAt(result.Count - 1);
int lastIdx = proposal.Pop();
candidate.Push(curIdx);
candidate.Push(lastIdx);
}
}
// Get result.
stroke.Verses = result;
for (int i = 0; i < nbVerses; ++i)
{
int requiredLength = stroke.Verses[i].Length;
int usedIdx = visited[i][visited[i].Count - 1];
if (!param.Reuse)
{
usedIndices[requiredLength].Add(usedIdx);
}
}
stroke.IsCompleted = true;
return(walk);
}
public void ClearPuzzleData()
{
puzzleData = null;
}