static bool Graph_divide(Graph& graph, size_t loops, PositionList* position_tbl) {
typedef std::set< size_t > NodeList;
NodeList nodes;
// nodes
for (Graph::const_iterator i = graph.begin(); i != graph.end(); ++i) {
nodes.insert(i->first);
}
while (!nodes.empty()) {
// BFS
Graph component;
std::deque< size_t > Q = boost::assign::list_of(*nodes.begin());
while (!Q.empty()) {
size_t xi = Q.front();
Q.pop_front();
if (nodes.find(xi) == nodes.end()) {
continue;
}
nodes.erase(xi);
Graph::const_iterator i = graph.find(xi);
if (i != graph.end()) {
for (Children::const_iterator j = i->second.children.begin(); j != i->second.children.end(); ++j) {
Graph_addEdge(component, xi, j->first, j->second);
Q.push_back(j->first);
}
for (Parents::const_iterator j = i->second.parents.begin(); j != i->second.parents.end(); ++j) {
Q.push_back(*j);
}
}
}
LOG4CXX_TRACE(logger, boost::format("component:%d/%d") % component.size() % graph.size());
if (!Graph_solve(component, loops, position_tbl)) {
LOG4CXX_ERROR(logger, "solve component failed");
return false;
}
}
return true;
}
Node * extractBestNode() {
// TODO use a better datastructure
if(nodes.empty()) {
return NULL;
}
NodeList::iterator best = nodes.begin();
float cost = std::numeric_limits<float>::max();
for(NodeList::iterator i = nodes.begin(); i != nodes.end(); ++i) {
if((*i)->getCost() < cost) {
cost = (*i)->getCost();
best = i;
}
}
Node * node = *best;
nodes.erase(best);
return node;
}
Edges *MaxAcyclicSubgraph::find_subgraph() {
Edges *Ea = new Edges;
stack< NodeList::iterator > toRemove;
NodeList *copy = copy_graph();
Node *node = NULL;
COLA_ASSERT(!copy->empty());
COLA_ASSERT(!edges->empty());
#ifdef COPY_ADJ_DEBUG
cout << "COPY OF MATRIX: " << endl;
printNodes(copy);
#endif
// while the graph is not empty
while (!copy->empty()) {
COLA_ASSERT(toRemove.empty());
// do we have any sinks
for (NodeList::iterator ni = copy->begin(); ni != copy->end(); ni++) {
// is is a sink if there are no outgoing edges
node = *ni;
if (node->outgoing.empty()) {
#ifdef RUN_DEBUG
cout << "vertex(" << node->id << ") is a SINK" << endl;
#endif
// append it's incoming edges to Ea
for (unsigned j = 0; j < node->incoming.size(); j++) {
#ifdef RUN_DEBUG
cout << "Appending to Ea: Edge(" << node->incoming[j].first << ", " << node->incoming[j].second << ")" << endl;
#endif
Ea->push_back(node->incoming[j]);
// find the edge from a vertex where the edge is outgoing
Node *out = NULL;
for (unsigned q = 0; q < copy->size(); q++) {
if ((*copy)[q]->id == node->incoming[j].first) { out = (*copy)[q]; }
}
COLA_ASSERT(out != NULL);
#ifdef RUN_DEBUG
cout << "Searching through OUTGOING list for vertex(" << out->id << ")" << endl;
#endif
Edges::iterator oi;
for (oi = out->outgoing.begin(); oi != out->outgoing.end(); oi++) {
cola::Edge e = *oi;
#ifdef RUN_DEBUG
cout << "Looking at Edge(" << e.first << ", " << e.second << ")" << endl;
#endif
if (e == node->incoming[j]) { break; }
}
#ifdef RUN_DEBUG
cout << "Erasing Edge(" << (*oi).first << ", " << (*oi).second << ") from OUTGOING list of vertex(" << out->id << ")" << endl;
#endif
out->outgoing.erase(oi);
}
// say that we want to remove this vertex from the graph.
toRemove.push(ni);
}
}
// remove all necessary vertices
while (!toRemove.empty()) { copy->erase(toRemove.top()); toRemove.pop(); } COLA_ASSERT(toRemove.empty());
#ifdef EA_DEBUG
cout << "EA: ";
for (unsigned i = 0; i < Ea->size(); i++) {
cout << "(" << (*Ea)[i].first << ", " << (*Ea)[i].second << ") ";
}
cout << endl;
#endif
#ifdef RUN_DEBUG
cout << "COPY OF MATRIX (after SINKS removed): " << endl;
printNodes(copy);
#endif
// do we have any isolated vertices
for (NodeList::iterator ni = copy->begin(); ni != copy->end(); ni++) {
// is is an isolated vertice if there are no incoming or outgoing edges
node = *ni;
if (node->incoming.empty() && node->outgoing.empty()) {
#ifdef RUN_DEBUG
cout << "vertex(" << node->id << ") is ISOLATED" << endl;
#endif
// say that we want to remove this vertex from the graph.
toRemove.push(ni);
}
}
// remove all necessary vertices
while (!toRemove.empty()) { copy->erase(toRemove.top()); toRemove.pop(); } COLA_ASSERT(toRemove.empty());
#ifdef EA_DEBUG
cout << "EA: ";
for (unsigned i = 0; i < Ea->size(); i++) {
cout << "(" << (*Ea)[i].first << ", " << (*Ea)[i].second << ") ";
}
cout << endl;
#endif
#ifdef RUN_DEBUG
cout << "COPY OF MATRIX (after isolated vertices removed): " << endl;
printNodes(copy);
#endif
// do we have any sources
for (NodeList::iterator ni = copy->begin(); ni != copy->end(); ni++) {
// is is a sink if there are no incoming edges
node = *ni;
if (node->incoming.empty()) {
#ifdef RUN_DEBUG
cout << "vertex(" << node->id << ") is a SOURCE" << endl;
#endif
// append it's outgoing edges to Ea
for (unsigned j = 0; j < node->outgoing.size(); j++) {
#ifdef RUN_DEBUG
cout << "Appending to Ea: Edge(" << node->outgoing[j].first << ", " << node->outgoing[j].second << ")" << endl;
#endif
Ea->push_back(node->outgoing[j]);
// find the edge from a vertex where the edge is incoming
Node *in = NULL;
for (unsigned q = 0; q < copy->size(); q++) {
if ((*copy)[q]->id == node->outgoing[j].second) { in = (*copy)[q]; }
}
COLA_ASSERT(in != NULL);
#ifdef RUN_DEBUG
cout << "Searching through INCOMING list for vertex(" << in->id << ")" << endl;
#endif
Edges::iterator ii;
for (ii = in->incoming.begin(); ii != in->incoming.end(); ii++) {
cola::Edge e = *ii;
#ifdef RUN_DEBUG
cout << "Looking at Edge(" << e.first << ", " << e.second << ")" << endl;
#endif
if (e == node->outgoing[j]) { break; }
}
#ifdef RUN_DEBUG
cout << "Erasing Edge(" << (*ii).first << ", " << (*ii).second << ") from INCOMING list of vertex(" << in->id << ")" << endl;
#endif
in->incoming.erase(ii);
}
// say that we want to remove this vertex from the graph.
toRemove.push(ni);
}
}
// remove all necessary vertices
while (!toRemove.empty()) { copy->erase(toRemove.top()); toRemove.pop(); } COLA_ASSERT(toRemove.empty());
#ifdef EA_DEBUG
cout << "EA: ";
for (unsigned i = 0; i < Ea->size(); i++) {
cout << "(" << (*Ea)[i].first << ", " << (*Ea)[i].second << ") ";
}
cout << endl;
#endif
#ifdef RUN_DEBUG
cout << "COPY OF MATRIX (after SOURCES removed): " << endl;
printNodes(copy);
#endif
// if the graph is not empty
if (!copy->empty()) {
// find the vertex with the highest degree of "source"
int degree = -1000;
NodeList::iterator theNode;
for (NodeList::iterator ni = copy->begin(); ni != copy->end(); ni++) {
node = *ni;
int t = node->outgoing.size() - node->incoming.size();
if (t > degree) {
#ifdef RUN_DEBUG
cout << "Sourceiest node: " << node->id << "(d:" << degree << ", t:" << t << ")" << endl;
#endif
degree = t;
theNode = ni;
}
}
// add this node's outgoing edges to Ea
node = *theNode;
for (unsigned j = 0; j < node->outgoing.size(); j++) {
#ifdef RUN_DEBUG
cout << "Appending to Ea: Edge(" << node->outgoing[j].first << ", " << node->outgoing[j].second << ")" << endl;
#endif
Ea->push_back(node->outgoing[j]);
// find the edge from a vertex where the edge is incoming
Node *in = NULL;
for (unsigned q = 0; q < copy->size(); q++) {
if ((*copy)[q]->id == node->outgoing[j].second) { in = (*copy)[q]; }
}
COLA_ASSERT(in != NULL);
#ifdef RUN_DEBUG
cout << "Searching through INCOMING list for vertex(" << in->id << ")" << endl;
#endif
Edges::iterator ii;
for (ii = in->incoming.begin(); ii != in->incoming.end(); ii++) {
cola::Edge e = *ii;
#ifdef RUN_DEBUG
cout << "Looking at Edge(" << e.first << ", " << e.second << ")" << endl;
#endif
if (e == node->outgoing[j]) { break; }
}
#ifdef RUN_DEBUG
cout << "Erasing Edge(" << (*ii).first << ", " << (*ii).second << ") from INCOMING list of vertex(" << in->id << ")" << endl;
#endif
in->incoming.erase(ii);
}
// for all of the incoming edges this node possesses, delete then from other node's outgoing edge list
for (unsigned j = 0; j < node->incoming.size(); j++) {
// find the edge from a vertex where the edge is outgoing
Node *out = NULL;
for (unsigned q = 0; q < copy->size(); q++) {
if ((*copy)[q]->id == node->incoming[j].first) { out = (*copy)[q]; }
}
COLA_ASSERT(out != NULL);
#ifdef RUN_DEBUG
cout << "Searching through OUTGOING list for vertex(" << out->id << ")" << endl;
#endif
Edges::iterator oi;
for (oi = out->outgoing.begin(); oi != out->outgoing.end(); oi++) {
cola::Edge e = *oi;
#ifdef RUN_DEBUG
cout << "Looking at Edge(" << e.first << ", " << e.second << ")" << endl;
#endif
if (e == node->incoming[j]) { break; }
}
#ifdef RUN_DEBUG
cout << "Erasing Edge(" << (*oi).first << ", " << (*oi).second << ") from OUTGOING list of vertex(" << out->id << ")" << endl;
#endif
out->outgoing.erase(oi);
}
// delete this vertex
copy->erase(theNode);
}
#ifdef EA_DEBUG
cout << "EA: ";
for (unsigned i = 0; i < Ea->size(); i++) {
cout << "(" << (*Ea)[i].first << ", " << (*Ea)[i].second << ") ";
}
cout << endl;
#endif
#ifdef RUN_DEBUG
cout << "COPY OF MATRIX (after SOURCIEST node removed): " << endl;
printNodes(copy);
#endif
}
// delete the copy
if (copy != NULL) {
for (unsigned i = 0; i < copy->size(); i++) { if ((*copy)[i] != NULL) { delete (*copy)[i]; } }
delete copy;
}
#ifdef EA_DEBUG
cout << "Returning EA: ";
for (unsigned i = 0; i < Ea->size(); i++) {
cout << "(" << (*Ea)[i].first << ", " << (*Ea)[i].second << ") ";
}
cout << endl;
#endif
return Ea;
}