Hello everybody, I am a newly boost user and have a problem in the following code. Since it is long, i put only the relevant parts. Could anyone help me please? When I try to get the vertices from a vector and put them to add_edge(), i get the following error massage : 'boost::add_edge' : cannot convert parameter 1 from 'char' to 'void *'   The problematic part is highlighted.   Code:typedefvector<Edge> simpleedgevector; vector<Edge>::iterator s_e_i;for simpleedge = Edge((*(*vec_it1)),(*(*vec_it1+1))); simpleedgevector.push_back(simpleedge);}edge_descriptor e; cout<< tie(e, inserted) = add_edge((*s_e_i).first, (*s_e_i).second, g); }for(s_e_i = simpleedgevector.begin();s_e_i != simpleedgevector.end();s_e_i++){boolinserted;"first part : "<<(*s_e_i).first<<" second part : "<<(*s_e_i).second< Edge;