VertSet intersection(const VertSet &set1, const VertSet &set2) {
VertSet result = VertSet();
for (VertSet_const_IT it = set1.begin(); it != set1.end(); it++) {
if (set2.find(*it) != set2.end()) {
result.insert(*it);
}
}
return result;
}
VertSet Vert::one_ring() {
VertSet result = VertSet();
Edge *e = edge;
do {
result.insert(e->pair->vert);
e = e->pair->prev;
} while(e != edge);
return result;
}
/**
* Return first path found from start vertex to end vertex
* as a vector of edges, or NULL of no such path is found.
*/
bool findDfsVertexPathMarking(vector<Vertex*> &path, Vertex *start, const Vertex *end)
{
mMarks.clear();
path.clear();
if (mEdges.find(start) != mEdges.end()) {
mMarks.insert(start);
path.push_back(start);
return findDfsVertexPathMarkingRec(path, end);
}
return false;
}
/**
* Add an edge if both vertices are non-NULL and distinct
*/
bool addEdge(Vertex *vertA, Vertex *vertB)
{
if (vertA == NULL || vertB == NULL || vertA == vertB)
return false; // no side effects on failure
addVertex(vertA);
addVertex(vertB);
if (mEdges.find(vertA) == mEdges.end()) {
mEdges.insert(EdgeMap::value_type(vertA, new VertSet()));
}
VertSet *nexts = mEdges.at(vertA);
return nexts->insert(vertB).second;
}
VertSet Vert::two_ring() {
VertSet result = VertSet();
VertSet first_ring = edge->vert->one_ring();
for (VertSet_IT it = first_ring.begin(); it != first_ring.end(); it++) {
VertSet temp_ring = (*it)->edge->vert->one_ring();
for (VertSet_IT it = temp_ring.begin(); it != temp_ring.end(); it++) {
result.insert(*it);
}
}
return result;
}
bool findDfsVertexPathMarkingRec(vector<Vertex*> &path, const Vertex *end)
{
Vertex *lastVert = path.back();
if (lastVert == end)
return true;
if (mEdges.find(lastVert) != mEdges.end()) {
VertSet *nexts = mEdges.at(lastVert);
for (VertSet::iterator it = nexts->begin(); it != nexts->end(); ++it) {
Vertex *vert = *it;
if (mMarks.find(vert) == mMarks.end()) {
mMarks.insert(vert);
path.push_back(vert);
bool found = findDfsVertexPathMarkingRec(path, end);
if ( found )
return found;
else
path.pop_back();
}
}
}
return false;
}
bool addVertex(Vertex *vert)
{
return mVerts.insert(vert).second;
}