c++11 - Populate a tree from vectors with BGL -


i have 2 vectors of objects need make tree structure them. let's assume have vector <obj> parents , vector <obj> leaves. therefore, each element of vector <obj> parents has several leaves sits @ end of tree. doing defining vertex properties , edges properties below, , define bidirectional graph:

struct vertexdata {     std::string obj_name; // concatenation of labels     std::string obj_class_num;     int num;     vector <int> segments_list;     bool is_leaf=false; };  struct edgedata {     std::string edge_name;     double confidence; };  typedef boost::adjacency_list<boost::vecs, boost::vecs,         boost::bidirectionals,         vertexdata,         boost::property<boost::edge_weight_t, double, edgedata> > graph;  graph graph;

  1. first approach: looping through vector <obj> leaves, each member, find parent , make edge. assign properties edge , vertices. next leaf, should check if has parent in tree or should add new vertex parent.

  2. second approach: thing tried, looping through vector <obj> parents, , each element try make leaves. not sure correct way this. here link: adding custom vertices boost graph try same iterations.

code added 1st approach:

vector <class1> parents; // has objects of type class1 vector <class2> leaves; // has objects of type class2  /// declare graph typedef boost::adjacency_list<boost::vecs, boost::vecs,         boost::bidirectionals,         vertexdata,         boost::property<boost::edge_weight_t, double, edgedata> > graph;  /// instantiate graph graph graph;  typedef boost::graph_traits<graph>::vertex_descriptor vertex_t; typedef boost::graph_traits<graph>::edge_descriptor edge_t; vector<vertex_t> obj_vertices; vector<string>   parents_labels_v; bool parent_exist=false;   /// loop through leaves , make edges associated parent (auto leaf: leaves) {      int leaf_nr = leaf.number;      vertex_t v = boost::add_vertex(graph); // leaf vertex     graph[v].num     = leaf_nr;         // leaf number     graph[v].is_leaf = true;     /// access parent label leaf number     string label1 = parents[leaf_nr].label;      /// check if parent exist, using label     if(std::find(parents_labels_v.begin(), parents_labels_v.end(), label1)        != parents_labels_v.end()){         parent_exist = true;     }else{         parents_labels_v.push_back(label1);     }      if(parent_exist) {         // find already_exist parent vertex make edge         vertex_t u = ???  here have problem         // create edge connecting 2 vertices         edge_t e; bool b;         boost::tie(e,b) = boost::add_edge(u,v,graph);     } else{         // if parent-vertex there not, add graph         vertex_t u = boost::add_vertex(graph); // parent vertex         graph[u].obj_name = label1;         graph[u].segments_list.push_back(leaf_nr);         obj_vertices.push_back(u);          // create edge connecting 2 vertices         edge_t e; bool b;         boost::tie(e,b) = boost::add_edge(u,v,graph);     }  }


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