MyGraph MyGraph::graph_union(const MyGraph& g2) const {
MyGraph output = copyGraph();
graph_hashmap::const_iterator g2_it = g2.thegraph.begin();
while(g2_it != this->thegraph.end()){
if ( output.thegraph.find(g2_it->first) == output.thegraph.end())
output.insertVertex(g2_it->first);
//cycle through all the edges contained in the node hashmap
node_hashmap::const_iterator node_iter = g2_it->second.begin();
while (node_iter != g2_it->second.end() ){
if (!output.areAdjacent(g2_it->first,node_iter->first))
output.insertEdge(g2_it->first,node_iter->first);
*node_iter++;
}
*g2_it++;
}
return output;
}
MyGraph MyGraph::graph_complement() const{
MyGraph output = copyGraph();
graph_hashmap::const_iterator g_iter = thegraph.begin();
my_set::const_iterator g2_iter;
while (g_iter != thegraph.end()){
g2_iter = set_of_vertices.begin();
while ( g2_iter != set_of_vertices.end()){
if (strcmp(g_iter->first.c_str(),(*g2_iter).c_str()) ){ //avoid self-loops
if( areAdjacent(g_iter->first, *g2_iter) )
output.removeEdge(g_iter->first, *g2_iter);
else
if (!output.areAdjacent(g_iter->first, *g2_iter))
output.insertEdge(g_iter->first, *g2_iter);
}
*g2_iter++;
}
*g_iter++;
}
return output;
}
MyGraph MyGraph::graph_intersection(const MyGraph& g2) const {
MyGraph output;
graph_hashmap::const_iterator g1_it = this->thegraph.begin();
while(g1_it != this->thegraph.end()){
//If the vertex in g1 does not exist in g2, then skip it.
if( g2.set_of_vertices.find(g1_it->first) != g2.set_of_vertices.end()) {
output.thegraph[g1_it->first]= node_hashmap();
//cycle through all the edges contained in the node hashmap
node_hashmap::const_iterator node_iter = g1_it->second.begin();
while (node_iter != g1_it->second.end() ){
if( this->thegraph.at(g1_it->first).find(node_iter->first) != thegraph.at(g1_it->first).end() &&
g2.thegraph.at(g1_it->first).find(node_iter->first) != g2.thegraph.at(g1_it->first).end()){
output.insertEdge(g1_it->first,node_iter->first);
}
*node_iter++;
}
}
*g1_it++;
}
return output;
}