// create a ring from the network. First find a spanning tree of the 
// graph network and then traverse the tree in order to create the
// ring.

*operation* Ring* create_ring()
*wrapper* Network
  (@ Adjacency* max_adj = max_degree_adj();
     cout << "***The maximum Degree node is " << *(max_adj->get_source()->get_id()) << endl;
     Tree* tree = max_adj->spanning_tree(this);
     Tree_Adjacency* root = tree->get_tree_adjacencies()->car();
     Ring* ring = new Ring(new VirtualAdjacency_List(), new DemNumber(0));
     root->traverse_tree(tree, ring, 0);
     ring->remove_lastadj();  // delete last vnode from ring
     this->build_jumps(tree, ring);
     ring->build_shortcuts();
     return_val = ring;
  @)

*operation* void print_ring()
*traverse*
  *from* Ring
  *to-stop* VirtualAdjacency
*wrapper* Ring
  (@
     cout << "Number of virtual nodes: " << get_vnode_count() << endl;
  @)
*wrapper* VirtualAdjacency
  (@ 
     VNode* vnode;
     vnode = this->get_source();
     cout << "Virtual Node: ";
     cout << vnode->get_vid() << "(" << vnode->get_phys_node()->get_id() << ")" << endl;
     cout << "   util = " << get_next_util() << endl;
     cout << "Jumps to virtual nodes:\n";
     this->print_jumps();
     cout << "Shortcuts to virtual nodes:\n";
     this->print_shortcuts();
  @)

*operation* void print_jumps()
*traverse*
  *from* VirtualAdjacency
  *through* -> *, jumps, *
  *to-stop* VNode
*wrapper* VNode
  (@ cout << this->get_vid() << "(" << this->get_phys_node()->get_id() << ")" << endl;
  @)
*wrapper* VirtualNeighbor
  *suffix*
  (@
     cout << "    util = " << get_util() << endl;
  @)

*operation* void print_shortcuts()
*traverse*
  *from* VirtualAdjacency
  *through* -> *, shortcuts, *
  *to-stop* VNode
*wrapper* VNode
  (@ cout << this->get_vid() << "(" << this->get_phys_node()->get_id() << ")" << endl;
  @)
*wrapper* VirtualNeighbor
  *suffix*
  (@
     cout << "    util = " << get_util() << endl;
  @)


// remove the last virtual adjacency from the ring
*operation* void remove_lastadj()
*wrapper* Ring
  (@
     VirtualAdjacency_List* NewVirtualAdjacencies = new VirtualAdjacency_List();
     VirtualAdjacency* adj;
     VirtualAdjacency_List* VirtualAdjacencies = get_start();
     
     adj = VirtualAdjacencies->get();
     while (VirtualAdjacencies->empty() != 0) {
       NewVirtualAdjacencies->append(adj);
       adj = VirtualAdjacencies->get();
     }
     adj->get_phys_node()->remove_lastvnode();
     this->set_start(NewVirtualAdjacencies);
  @)

// remove the last vnode from the list of vnodes of a physical node

*operation* void remove_lastvnode()
*wrapper* Node
  (@
     VNode_ParList* vnodes = this->get_vnodes();
     VNode_ParList* new_vnodes = new VNode_ParList();
     VNode* vnode;
     vnode = vnodes->get();
     while (vnodes->empty() != 0) {
       new_vnodes->append(vnode);
       vnode = vnodes->get();
     }
     this->set_vnodes(new_vnodes);
  @)




// add a virtual node to the ring

*operation* void add_vnode(int& vcount, Node* node)
*wrapper* Ring
  (@ 
    VNode* vnode = new VNode(new DemNumber(vcount), node);
    node->get_vnodes()->append(vnode);    
    VirtualAdjacency* new_adj = new VirtualAdjacency(vnode,
			   	     new DemReal(0.0),  // next link util
				     new DemReal(0.0),  // next past util
				     new DemReal(0.0),  // next total flow
                                     new VirtualNeighbor_List(),  //shortcuts
                                     new VirtualNeighbor_List()); //jumps
    this->get_start()->append(new_adj);
    this->get_vnode_count()->set_val(vcount);
    vcount++;
  @)