void findEulerTour(std::vector<T_Key>* sortedOutp) {
UASSERT(sortedOutp->empty(), "Output graph must start empty");
if (debug() >= 6) dumpDotFilePrefixed("findEulerTour");
vl_unordered_set<unsigned /*edgeID*/> markedEdges;
// Pick a start node
Vertex* start_vertexp = castVertexp(verticesBeginp());
findEulerTourRecurse(&markedEdges, start_vertexp, sortedOutp);
}
void V3Graph::userClearEdges() {
// Clear user() in all of tree
for (V3GraphVertex* vertexp = verticesBeginp(); vertexp; vertexp=vertexp->verticesNextp()) {
for (V3GraphEdge* edgep = vertexp->outBeginp(); edgep; edgep=edgep->outNextp()) {
edgep->user(0);
edgep->userp(NULL); // Its a union, but might be different size than user()
}
}
}
void V3Graph::clear() {
// Empty it of all points, as if making a new object
// Delete the old edges
for (V3GraphVertex* vertexp = verticesBeginp(); vertexp; vertexp=vertexp->verticesNextp()) {
for (V3GraphEdge* edgep = vertexp->outBeginp(); edgep; /*BELOW*/) {
V3GraphEdge* nextp = edgep->outNextp();
delete edgep;
edgep = nextp;
}
vertexp->outUnlink();
}
// Delete the old vertices
for (V3GraphVertex* vertexp = verticesBeginp(); vertexp; /*BELOW*/) {
V3GraphVertex* nextp = vertexp->verticesNextp();
delete vertexp;
vertexp = nextp;
}
verticesUnlink();
}
void V3Graph::userClearVertices() {
// Clear user() in all of tree
// We may use the userCnt trick in V3Ast later... (but gblCnt would be
// in V3Graph instead of static - which has the complication of finding
// the graph pointer given a vertex.) For now we don't call this often, and
// the extra code on each read of user() would probably slow things
// down more than help.
for (V3GraphVertex* vertexp = verticesBeginp(); vertexp; vertexp=vertexp->verticesNextp()) {
vertexp->user(0);
vertexp->userp(NULL); // Its a union, but might be different size than user()
}
}
void dumpGraph(std::ostream& os, const string& nameComment) const {
// UINFO(0) as controlled by caller
os<<"At "<<nameComment<<", dumping graph. Keys:\n";
for (V3GraphVertex* vxp = verticesBeginp(); vxp; vxp = vxp->verticesNextp()) {
Vertex* tspvp = castVertexp(vxp);
os<<" "<<tspvp->key()<<endl;
for (V3GraphEdge* edgep = tspvp->outBeginp(); edgep; edgep = edgep->outNextp()) {
Vertex* neighborp = castVertexp(edgep->top());
os<<" has edge "<<edgep->user()<<" to "<<neighborp->key()<<endl;
}
}
}
std::vector<T_Key> getOddDegreeKeys() const {
std::vector<T_Key> result;
for (V3GraphVertex* vxp = verticesBeginp(); vxp; vxp = vxp->verticesNextp()) {
Vertex* tspvp = castVertexp(vxp);
vluint32_t degree = 0;
for (V3GraphEdge* edgep = vxp->outBeginp(); edgep; edgep = edgep->outNextp()) {
degree++;
}
if (degree & 1) {
result.push_back(tspvp->key());
}
}
return result;
}
void V3Graph::dump(ostream& os) {
// This generates a file used by graphviz, http://www.graphviz.org
os<<" Graph:\n";
// Print vertices
for (V3GraphVertex* vertexp = verticesBeginp(); vertexp; vertexp=vertexp->verticesNextp()) {
os<<"\tNode: "<<vertexp->name();
if (vertexp->color()) os<<" color="<<vertexp->color();
os<<endl;
// Print edges
for (V3GraphEdge* edgep = vertexp->inBeginp(); edgep; edgep=edgep->inNextp()) {
dumpEdge (os, vertexp, edgep);
}
for (V3GraphEdge* edgep = vertexp->outBeginp(); edgep; edgep=edgep->outNextp()) {
dumpEdge (os, vertexp, edgep);
}
}
}
void V3Graph::dumpDotFile(const string& filename, bool colorAsSubgraph) {
// This generates a file used by graphviz, http://www.graphviz.org
// "hardcoded" parameters:
const auto_ptr<ofstream> logp (V3File::new_ofstream(filename));
if (logp->fail()) v3fatalSrc("Can't write "<<filename);
// Header
*logp<<"digraph v3graph {\n";
*logp<<"\tgraph\t[label=\""<<filename<<"\",\n";
*logp<<"\t\t labelloc=t, labeljust=l,\n";
*logp<<"\t\t //size="<<"\"7.5,10\","<<"\n";
*logp<<"\t\t rankdir="<<dotRankDir()<<"];\n";
// List of all possible subgraphs
typedef multimap<string,V3GraphVertex*> SubgraphMmap;
SubgraphMmap subgraphs;
for (V3GraphVertex* vertexp = verticesBeginp(); vertexp; vertexp=vertexp->verticesNextp()) {
string vertexSubgraph = (colorAsSubgraph && vertexp->color()) ? cvtToStr(vertexp->color()) : "";
subgraphs.insert(make_pair(vertexSubgraph, vertexp));
}
// We use a map here, as we don't want to corrupt anything (userp) in the graph,
// and we don't care if this is slow.
map<V3GraphVertex*,int> numMap;
// Print vertices
int n=0;
string subgr;
for (SubgraphMmap::iterator it = subgraphs.begin(); it!=subgraphs.end(); ++it) {
string vertexSubgraph = it->first;
V3GraphVertex* vertexp = it->second;
numMap[vertexp] = n;
if (subgr != vertexSubgraph) {
if (subgr!="") *logp<<"\t};\n";
subgr = vertexSubgraph;
if (subgr!="") *logp<<"\tsubgraph cluster_"<<subgr<<" {\n";
}
if (subgr!="") *logp<<"\t";
*logp<<"\tn"<<vertexp->dotName()<<(n++)
<<"\t[fontsize=8 "
<<"label=\""<<(vertexp->name()!="" ? vertexp->name() : "\\N");
if (vertexp->rank()) *logp<<" r"<<vertexp->rank();
if (vertexp->fanout()) *logp<<" f"<<vertexp->fanout();
if (vertexp->color()) *logp<<"\\n c"<<vertexp->color();
*logp<<"\"";
*logp<<", color="<<vertexp->dotColor();
if (vertexp->dotStyle()!="") *logp<<", style="<<vertexp->dotStyle();
if (vertexp->dotShape()!="") *logp<<", shape="<<vertexp->dotShape();
*logp<<"];\n";
}
if (subgr!="") *logp<<"\t};\n";
// Print edges
for (V3GraphVertex* vertexp = verticesBeginp(); vertexp; vertexp=vertexp->verticesNextp()) {
for (V3GraphEdge* edgep = vertexp->outBeginp(); edgep; edgep=edgep->outNextp()) {
if (edgep->weight()) {
int fromVnum = numMap[edgep->fromp()];
int toVnum = numMap[edgep->top()];
*logp<<"\tn"<<edgep->fromp()->dotName()<<fromVnum
<<" -> n"<<edgep->top()->dotName()<<toVnum
<<" ["
//<<"fontsize=8 label=\""<<(edgep->name()!="" ? edgep->name() : "\\E")<<"\""
<<"fontsize=8 label=\""<<(edgep->dotLabel()!="" ? edgep->dotLabel() : "")<<"\""
<<" weight="<<edgep->weight()
<<" color="<<edgep->dotColor();
if (edgep->dotStyle()!="") *logp<<" style="<<edgep->dotStyle();
//if (edgep->cutable()) { *logp<<",constraint=false"; } // to rank without following edges
*logp<<"];\n";
}
}
}
// Vertex::m_user end, now unused
// Trailer
*logp << "}\n";
logp->close();
cout << "dot -Tpdf -o ~/a.pdf "<<filename<<endl;
}
void V3Graph::clearColors() {
// Reset colors
for (V3GraphVertex* vertexp = verticesBeginp(); vertexp; vertexp=vertexp->verticesNextp()) {
vertexp->m_color = 0;
}
}
// From *this, populate *mstp with the minimum spanning tree.
// *mstp must be initially empty.
void makeMinSpanningTree(TspGraphTmpl* mstp) {
UASSERT(mstp->empty(), "Output graph must start empty");
// Use Prim's algorithm to efficiently construct the MST.
vl_unordered_set<Vertex*> visited_set;
EdgeCmp cmp;
typedef std::set<V3GraphEdge*, EdgeCmp&> PendingEdgeSet;
// This is the set of pending edges from visited to unvisited
// nodes.
PendingEdgeSet pendingEdges(cmp);
vluint32_t vertCount = 0;
for (V3GraphVertex* vxp = verticesBeginp();
vxp; vxp = vxp->verticesNextp()) {
mstp->addVertex(castVertexp(vxp)->key());
vertCount++;
}
// Choose an arbitrary start vertex and visit it;
// all incident edges from this vertex go into a pending edge set.
Vertex* start_vertexp = castVertexp(verticesBeginp());
visited_set.insert(start_vertexp);
for (V3GraphEdge* edgep = start_vertexp->outBeginp();
edgep; edgep = edgep->outNextp()) {
pendingEdges.insert(edgep);
}
// Repeatedly find the least costly edge in the pending set.
// If it connects to an unvisited node, visit that node and update
// the pending edge set. If it connects to an already visited node,
// discard it and repeat again.
unsigned edges_made = 0;
while (!pendingEdges.empty()) {
typename PendingEdgeSet::iterator firstIt = pendingEdges.begin();
V3GraphEdge* bestEdgep = *firstIt;
pendingEdges.erase(firstIt);
// bestEdgep->fromp() should be already seen
Vertex* from_vertexp = castVertexp(bestEdgep->fromp());
UASSERT(visited_set.find(from_vertexp) != visited_set.end(), "Can't find vertex");
// If the neighbor is not yet visited, visit it and add its edges
// to the pending set.
Vertex* neighborp = castVertexp(bestEdgep->top());
if (visited_set.find(neighborp) == visited_set.end()) {
int bestCost = bestEdgep->weight();
UINFO(6, "bestCost = "<<bestCost
<<" from "<<from_vertexp->key()
<<" to "<<neighborp->key()<<endl);
// Create the edge in our output MST graph
mstp->addEdge(from_vertexp->key(), neighborp->key(), bestCost);
edges_made++;
// Mark this vertex as visited
visited_set.insert(neighborp);
// Update the pending edges with new edges
for (V3GraphEdge* edgep = neighborp->outBeginp();
edgep; edgep = edgep->outNextp()) {
pendingEdges.insert(edgep);
}
} else {
UINFO(6, "Discarding edge to already-visited neighbor "
<<neighborp->key()<<endl);
}
}
UASSERT(edges_made + 1 == vertCount, "Algorithm failed");
UASSERT(visited_set.size() == vertCount, "Algorithm failed");
}
