public Dictionary <int, Dictionary <PartialSolution, int> > Forget(TDNode bag, Vertex[] vertices, Dictionary <int, Dictionary <PartialSolution, int> > table)
{
forgetSW.Start();
Dictionary <int, Dictionary <PartialSolution, int> > result = new Dictionary <int, Dictionary <PartialSolution, int> >();
int vertexMask = 0;
foreach (Vertex v in vertices)
{
vertexMask |= (1 << v.Color);
}
byte[] tempUF = new byte[bag.ParentDecomposition.Width];
foreach (KeyValuePair <int, Dictionary <PartialSolution, int> > kvp in table)
{
int subset = kvp.Key;
int newSubset = subset & ~vertexMask;
Dictionary <PartialSolution, int> newDict = null;
if (!result.TryGetValue(newSubset, out newDict))
{
newDict = new Dictionary <PartialSolution, int>();
result.Add(newSubset, newDict);
}
foreach (KeyValuePair <PartialSolution, int> kvp2 in kvp.Value)
{
if (kvp2.Key.CountComponents() != kvp2.Key.CountComponents(newSubset))
{
continue; // Check whether set remains connected
}
VertexSubset newVertexSubset = VertexSubset.Create(bag, newSubset, kvp2.Key.Subset, null);
PartialSolution newPs = new PartialSolution(newVertexSubset, kvp2.Key);
Upsert(newDict, newPs, kvp2.Value);
}
}
foreach (KeyValuePair <int, Dictionary <PartialSolution, int> > kvp in table.ToList())
{
table[kvp.Key] = RankBased.Reduce(kvp.Value, 0.125);
}
forgetSW.Stop();
Program.TableCount += result.Values.Sum((t) => t.Count);
return(result);
}
// Joins two tables that have partial solutions with one type of vertex subset
public Dictionary <PartialSolution, int> JoinTwo(TDNode bag, List <int> verticesInvolved, Dictionary <PartialSolution, int> leftTable, Dictionary <PartialSolution, int> rightTable)
{
Dictionary <PartialSolution, int> newTable = new Dictionary <PartialSolution, int>();
// Reducing before Join is almost certainly beneficial, use a low threshold
leftTable = RankBased.Reduce(leftTable, 0.999);
rightTable = RankBased.Reduce(rightTable, 0.999);
KeyValuePair <PartialSolution, int>[] rightCopy = rightTable.ToArray();
foreach (KeyValuePair <PartialSolution, int> leftSol in leftTable)
{
foreach (KeyValuePair <PartialSolution, int> rightSol in rightCopy)
{
VertexSubset newSubset = VertexSubset.Create(bag, leftSol.Key.Subset.LocalSubset, leftSol.Key.Subset, rightSol.Key.Subset);
PartialSolution newSol = new PartialSolution(newSubset, leftSol.Key);
bool good = true;
foreach (int i in verticesInvolved)
{
byte rep = rightSol.Key.Find(i);
if (rep == i)
{
continue;
}
if (newSol.Find(i) == newSol.Find(rep))
{
good = false; break;
}
newSol.Union(i, rep);
}
if (good)
{
Upsert(newTable, newSol, leftSol.Value + rightSol.Value);
}
}
}
// Do not call reduce here: the forget, introduce or join bag that comes next will take care of it
//newTable = RankBased.Reduce(newTable, 0.5);
return(newTable);
}
public Dictionary <int, Dictionary <PartialSolution, int> > Introduce(TDNode bag, Vertex[] vertices, Dictionary <int, Dictionary <PartialSolution, int> > table)
{
introSW.Start();
Vertex[] terminals = vertices.Where((v) => v.IsTerminal).ToArray();
Vertex[] nonterminals = vertices.Where((v) => !v.IsTerminal).ToArray();
Dictionary <int, Dictionary <PartialSolution, int> > result = new Dictionary <int, Dictionary <PartialSolution, int> >();
for (int i = 0; i < (1 << nonterminals.Length); i++)
{
List <Vertex> toAdd = new List <Vertex>(terminals.Length + i.BitCount());
foreach (Vertex v in terminals)
{
toAdd.Add(v);
}
for (int j = 0; j < nonterminals.Length; j++)
{
if ((i & (1 << j)) != 0)
{
toAdd.Add(nonterminals[j]);
}
}
int addMask = 0;
foreach (Vertex v in toAdd)
{
addMask |= (1 << v.Color);
}
List <Edge> introEdges = new List <Edge>();
foreach (Vertex v in toAdd)
{
foreach (Edge e in v.Adj)
{
if (bag.Bag.Contains(e.To) && !introEdges.Contains(e))
{
introEdges.Add(e);
}
}
}
foreach (KeyValuePair <int, Dictionary <PartialSolution, int> > kvp in table)
{
int subset = kvp.Key;
int newSubset = subset | addMask;
Dictionary <PartialSolution, int> newDict = new Dictionary <PartialSolution, int>();
Dictionary <PartialSolution, int> localTable = RankBased.Reduce(kvp.Value, 0.999);
foreach (KeyValuePair <PartialSolution, int> kvp2 in localTable)
{
VertexSubset newVertexSubset = VertexSubset.Create(bag, newSubset, kvp2.Key.Subset, null);
newDict.Add(new PartialSolution(newVertexSubset, kvp2.Key), kvp2.Value);
}
if (introEdges.Where((e) => (newSubset & (1 << e.To.Color)) != 0).Count() > 2)
{
// Efficient method of introducing multiple edges at once and simultaneously running RankBased Reduce
//newDict = IntroduceEdgesIntoTable(newDict, introEdges.Where((e) => (newSubset & (1 << e.To.Color)) != 0).ToArray());
newDict = IntroduceEdgesIntoTable(newDict, introEdges.Where((e) => (newSubset & (1 << e.To.Color)) != 0).ToArray());
}
else
{
foreach (Edge e in introEdges)
{
if ((newSubset & (1 << e.To.Color)) != 0)
{
newDict = RankBased.Reduce(IntroduceEdge(newDict, e), 0.125);
}
}
}
if (newDict.Count > 0)
{
result.Add(newSubset, newDict);
}
}
}
introSW.Stop();
Program.TableCount += result.Values.Sum((t) => t.Count);
return(result);
}