//
// Integer-based representation of the main hypergraph
//
public PebblerHypergraph <T, A> GetPebblerHypergraph()
{
//
// Strictly create the nodes
//
PebblerHyperNode <T, A>[] pebblerNodes = new PebblerHyperNode <T, A> [vertices.Count];
for (int v = 0; v < vertices.Count; v++)
{
pebblerNodes[v] = vertices[v].CreatePebblerNode();
}
//
// Non-redundantly create all hyperedges
//
for (int v = 0; v < vertices.Count; v++)
{
foreach (HyperEdge <A> edge in vertices[v].edges)
{
// Only add once to all nodes when this is the 'minimum' source node
if (v == edge.sourceNodes.Min())
{
PebblerHyperEdge <A> newEdge = new PebblerHyperEdge <A>(edge.sourceNodes, edge.targetNode, edge.annotation);
foreach (int src in edge.sourceNodes)
{
pebblerNodes[src].AddEdge(newEdge);
}
}
}
}
return(new PebblerHypergraph <T, A>(pebblerNodes));
}
//
// The combination of new information may lead to other given information being deducible
//
//
// foreach given in the problem
// find all edges with target given
// foreach edge with target with given
// if (all of the source nodes in edge are in the given OR path) then
// if this is a minimal edge (fewer sources better) then
// save edge
// if (found edge) then
// AddEdge to problem
// move target given to path
//
private void PerformDeducibilityCheck(HyperEdgeMultiMap <A> edgeDatabase)
{
// All the givens and path nodes for this problem; this includes the new edgeSources
List <int> problemGivensAndPath = new List <int>(this.givens);
problemGivensAndPath.AddRange(this.path);
// foreach given in the problem
List <int> tempGivens = new List <int>(this.givens); // Make a copy because we may be modifying it below
foreach (int given in tempGivens)
{
PebblerHyperEdge <A> savedEdge = null;
// find all edges with target given
List <PebblerHyperEdge <A> > forwardEdges = edgeDatabase.GetBasedOnGoal(given);
if (forwardEdges != null)
{
// foreach edge with target with given
foreach (PebblerHyperEdge <A> edge in forwardEdges)
{
// if (all of the source nodes in edge are in the given OR path) then
if (Utilities.Subset <int>(problemGivensAndPath, edge.sourceNodes))
{
// if this is a minimal edge (fewer sources better) then
if (savedEdge == null)
{
savedEdge = edge;
}
else if (edge.sourceNodes.Count < savedEdge.sourceNodes.Count)
{
savedEdge = edge;
}
}
}
if (savedEdge != null)
{
// if (Utilities.PROBLEM_GEN_DEBUG) System.Diagnostics.Debug.WriteLine("CTA: Found another edge which can deduce givens." + savedEdge);
// Add the found edge to the problem
this.AddEdge(savedEdge);
// move target given to path: (1) remove from givens; (2) add to path
this.givens.Remove(savedEdge.targetNode);
Utilities.AddUnique <int>(this.path, savedEdge.targetNode);
}
}
}
}
public Problem(PebblerHyperEdge <A> edge)
{
givens = new List <int>(edge.sourceNodes);
goal = edge.targetNode;
path = new List <int>();
edges = new List <PebblerHyperEdge <A> >();
edges.Add(edge);
suppressedGivens = new List <int>();
graph = new DiGraph();
graph.AddHyperEdge(givens, goal);
}
private void AddEdge(PebblerHyperEdge <A> edge)
{
// Add to the graph
graph.AddHyperEdge(edge.sourceNodes, edge.targetNode);
if (this.edges.Contains(edge))
{
return;
}
// Add in an ordered manner according to the target node.
int e = 0;
for ( ; e < this.edges.Count; e++)
{
if (edge.targetNode < this.edges[e].targetNode)
{
break;
}
}
this.edges.Insert(e, edge);
}
