deba@262: // -*- c++ -*-
deba@262: #ifndef HUGO_LIST_GRAPH_H
deba@262: #define HUGO_LIST_GRAPH_H
deba@262: 
deba@262: #include <iostream>
deba@262: #include <vector>
deba@262: 
deba@262: #include <invalid.h>
deba@262: 
deba@340: #include "vector_map.h"
deba@340: #include "edge_map_registry.h"
deba@340: #include "node_map_registry.h"
deba@340: #include "edge_map_base.h"
deba@340: #include "node_map_base.h"
deba@340: 
deba@262: namespace hugo {
deba@262: 
deba@262:   template <typename It>
deba@262:   int count(It it) { 
deba@262:     int i=0;
deba@262:     for( ; it.valid(); ++it) { ++i; } 
deba@262:     return i;
deba@262:   }
deba@262: 
deba@262:   class ListGraph {
deba@262:     class node_item;
deba@262:     class edge_item;
deba@262:   public:
deba@262:     class Node;
deba@262:     class NodeIt;
deba@262:     class Edge;
deba@262:     class EdgeIt;
deba@262:     class OutEdgeIt;
deba@262:     class InEdgeIt;
deba@262:     class SymEdgeIt;
deba@262:     
deba@340: //    template <typename T> class NodeMap;
deba@340: //    template <typename T> class EdgeMap;
deba@262:   private:
deba@340: //    template <typename T> friend class NodeMap;
deba@340:  //   template <typename T> friend class EdgeMap;
deba@262:  
deba@340: 		NodeMapRegistry<ListGraph, Node> node_maps;
deba@262: 
deba@262:     template <typename T>
deba@340:     class NodeMap : public VectorMap<ListGraph, Edge, T, EdgeMapBase> {};
deba@340: 		
deba@340: 		EdgeMapRegistry<ListGraph, Edge> edge_maps;
deba@340: 
deba@340:     template <typename T>
deba@340:     class EdgeMap : public VectorMap<Graph, Node, T, NodeMapBase> {};
deba@340: 
deba@262: 
deba@262:     int node_id;
deba@262:     int edge_id;
deba@262:     int _node_num;
deba@262:     int _edge_num;
deba@262: 
deba@262:     node_item* _first_node;
deba@262:     node_item* _last_node;
deba@262: 
deba@262:     class node_item {
deba@262:       friend class ListGraph;
deba@262:       template <typename T> friend class NodeMap;
deba@262:       
deba@262:       friend class Node;
deba@262:       friend class NodeIt;
deba@262:       friend class Edge;
deba@262:       friend class EdgeIt;
deba@262:       friend class OutEdgeIt;
deba@262:       friend class InEdgeIt;
deba@262:       friend class SymEdgeIt;
deba@262:       friend std::ostream& operator<<(std::ostream& os, const Node& i);
deba@262:       friend std::ostream& operator<<(std::ostream& os, const Edge& i);
deba@262:       //ListGraph* G;
deba@262:       int id;
deba@262:       edge_item* _first_out_edge;
deba@262:       edge_item* _last_out_edge;
deba@262:       edge_item* _first_in_edge;
deba@262:       edge_item* _last_in_edge;
deba@262:       node_item* _next_node;
deba@262:       node_item* _prev_node;
deba@262:     public:
deba@262:       node_item() { }
deba@262:     };
deba@262: 
deba@262:     class edge_item {
deba@262:       friend class ListGraph;
deba@262:       template <typename T> friend class EdgeMap;
deba@262: 
deba@262:       friend class Node;
deba@262:       friend class NodeIt;
deba@262:       friend class Edge;
deba@262:       friend class EdgeIt;
deba@262:       friend class OutEdgeIt;
deba@262:       friend class InEdgeIt;
deba@262:       friend class SymEdgeIt;
deba@262:       friend std::ostream& operator<<(std::ostream& os, const Edge& i);
deba@262:       //ListGraph* G;
deba@262:       int id;
deba@262:       node_item* _tail;
deba@262:       node_item* _head;
deba@262:       edge_item* _next_out;
deba@262:       edge_item* _prev_out;
deba@262:       edge_item* _next_in;
deba@262:       edge_item* _prev_in;
deba@262:     public:
deba@262:       edge_item() { }
deba@262:     };
deba@262: 
deba@262:     node_item* _add_node() { 
deba@262:       node_item* p=new node_item;
deba@262:       p->id=node_id++;
deba@262:       p->_first_out_edge=0;
deba@262:       p->_last_out_edge=0;
deba@262:       p->_first_in_edge=0;
deba@262:       p->_last_in_edge=0;
deba@262:       p->_prev_node=_last_node;
deba@262:       p->_next_node=0;
deba@262:       if (_last_node) _last_node->_next_node=p;
deba@262:       _last_node=p;
deba@262:       if (!_first_node) _first_node=p;
deba@262: 
deba@262:       ++_node_num;
deba@262:       return p;
deba@262:     }
deba@262: 
deba@262:     edge_item* _add_edge(node_item* _tail, node_item* _head) {
deba@262:       edge_item* e=new edge_item;
deba@262:       e->id=edge_id++;
deba@262:       e->_tail=_tail;
deba@262:       e->_head=_head;
deba@262:       
deba@262:       e->_prev_out=_tail->_last_out_edge;
deba@262:       if (_tail->_last_out_edge) (_tail->_last_out_edge)->_next_out=e;
deba@262:       _tail->_last_out_edge=e;
deba@262:       if (!_tail->_first_out_edge) _tail->_first_out_edge=e; 
deba@262:       e->_next_out=0;
deba@262:  
deba@262:       e->_prev_in=_head->_last_in_edge;
deba@262:       if (_head->_last_in_edge) (_head->_last_in_edge)->_next_in=e;
deba@262:       _head->_last_in_edge=e;
deba@262:       if (!_head->_first_in_edge) { _head->_first_in_edge=e; } 
deba@262:       e->_next_in=0;
deba@262: 
deba@262:       ++_edge_num;
deba@262:       return e;
deba@262:     }
deba@262: 
deba@262:     //deletes a node which has no out edge and no in edge
deba@262:     void _delete_node(node_item* v) {
deba@262:       if (v->_next_node) (v->_next_node)->_prev_node=v->_prev_node; else 
deba@262: 	_last_node=v->_prev_node;
deba@262:       if (v->_prev_node) (v->_prev_node)->_next_node=v->_next_node; else 
deba@262: 	_first_node=v->_next_node;
deba@262: 
deba@262:       delete v;
deba@262:       --_node_num;
deba@262:     }
deba@262: 
deba@262:     void _delete_edge(edge_item* e) {
deba@262:       if (e->_next_out) (e->_next_out)->_prev_out=e->_prev_out; else 
deba@262: 	(e->_tail)->_last_out_edge=e->_prev_out;
deba@262:       if (e->_prev_out) (e->_prev_out)->_next_out=e->_next_out; else 
deba@262: 	(e->_tail)->_first_out_edge=e->_next_out;
deba@262:       if (e->_next_in) (e->_next_in)->_prev_in=e->_prev_in; else 
deba@262: 	(e->_head)->_last_in_edge=e->_prev_in;
deba@262:       if (e->_prev_in) (e->_prev_in)->_next_in=e->_next_in; else 
deba@262: 	(e->_head)->_first_in_edge=e->_next_in;
deba@262: 
deba@262:       delete e;
deba@262:       --_edge_num;
deba@262:     }
deba@262: 
deba@262:     void _set_tail(edge_item* e, node_item* _tail) {
deba@262:       if (e->_next_out) (e->_next_out)->_prev_out=e->_prev_out; else 
deba@262: 	(e->_tail)->_last_out_edge=e->_prev_out;
deba@262:       if (e->_prev_out) (e->_prev_out)->_next_out=e->_next_out; else 
deba@262: 	(e->_tail)->_first_out_edge=e->_next_out;
deba@262:       
deba@262:       e->_tail=_tail;
deba@262:       
deba@262:       e->_prev_out=_tail->_last_out_edge;
deba@262:       if (_tail->_last_out_edge) (_tail->_last_out_edge)->_next_out=e;
deba@262:       _tail->_last_out_edge=e;
deba@262:       if (!_tail->_first_out_edge) _tail->_first_out_edge=e; 
deba@262:       e->_next_out=0;
deba@262:     }
deba@262: 
deba@262:     void _set_head(edge_item* e, node_item* _head) {
deba@262:       if (e->_next_in) (e->_next_in)->_prev_in=e->_prev_in; else 
deba@262: 	(e->_head)->_last_in_edge=e->_prev_in;
deba@262:       if (e->_prev_in) (e->_prev_in)->_next_in=e->_next_in; else 
deba@262: 	(e->_head)->_first_in_edge=e->_next_in;
deba@262:       
deba@262:       e->_head=_head;
deba@262:       
deba@262:       e->_prev_in=_head->_last_in_edge;
deba@262:       if (_head->_last_in_edge) (_head->_last_in_edge)->_next_in=e;
deba@262:       _head->_last_in_edge=e;
deba@262:       if (!_head->_first_in_edge) { _head->_first_in_edge=e; } 
deba@262:       e->_next_in=0;
deba@262:     }
deba@262: 
deba@262:   public:
deba@262: 
deba@262:     /* default constructor */
deba@262: 
deba@262:     ListGraph() : node_id(0), edge_id(0), _node_num(0), _edge_num(0), _first_node(0), _last_node(0) { }
deba@262:     
deba@262:     ~ListGraph() { 
deba@262:       while (first<NodeIt>().valid()) erase(first<NodeIt>());
deba@262:     }
deba@262: 
deba@262:     int nodeNum() const { return _node_num; }
deba@262:     int edgeNum() const { return _edge_num; }
deba@262: 
deba@262:     /* functions to construct iterators from the graph, or from each other */
deba@262: 
deba@262:     //NodeIt firstNode() const { return NodeIt(*this); }
deba@262:     //EdgeIt firstEdge() const { return EdgeIt(*this); }
deba@262:     
deba@262:     //OutEdgeIt firstOutEdge(const Node v) const { return OutEdgeIt(v); }
deba@262:     //InEdgeIt firstInEdge(const Node v) const { return InEdgeIt(v); }
deba@262:     //SymEdgeIt firstSymEdge(const Node v) const { return SymEdgeIt(v); }
deba@262:     Node tail(Edge e) const { return e.tailNode(); }
deba@262:     Node head(Edge e) const { return e.headNode(); }
deba@262: 
deba@262:     Node aNode(const OutEdgeIt& e) const { return e.aNode(); }
deba@262:     Node aNode(const InEdgeIt& e) const { return e.aNode(); }
deba@262:     Node aNode(const SymEdgeIt& e) const { return e.aNode(); }
deba@262: 
deba@262:     Node bNode(const OutEdgeIt& e) const { return e.bNode(); }
deba@262:     Node bNode(const InEdgeIt& e) const { return e.bNode(); }
deba@262:     Node bNode(const SymEdgeIt& e) const { return e.bNode(); }
deba@262: 
deba@262:     //Node invalid_node() { return Node(); }
deba@262:     //Edge invalid_edge() { return Edge(); }
deba@262:     //OutEdgeIt invalid_out_edge() { return OutEdgeIt(); }
deba@262:     //InEdgeIt invalid_in_edge() { return InEdgeIt(); }
deba@262:     //SymEdgeIt invalid_sym_edge() { return SymEdgeIt(); }
deba@262: 
deba@262:     /* same methods in other style */
deba@262:     /* for experimental purpose */
deba@262: 
deba@262:     NodeIt& /*getF*/first(NodeIt& v) const { 
deba@262:       v=NodeIt(*this); return v; }
deba@262:     EdgeIt& /*getF*/first(EdgeIt& e) const { 
deba@262:       e=EdgeIt(*this); return e; }
deba@262:     OutEdgeIt& /*getF*/first(OutEdgeIt& e, Node v) const { 
deba@262:       e=OutEdgeIt(*this, v); return e; }
deba@262:     InEdgeIt& /*getF*/first(InEdgeIt& e, Node v) const { 
deba@262:       e=InEdgeIt(*this, v); return e; }
deba@262:     SymEdgeIt& /*getF*/first(SymEdgeIt& e, Node v) const { 
deba@262:       e=SymEdgeIt(*this, v); return e; }
deba@262:     //void getTail(Node& n, const Edge& e) const { n=tail(e); }
deba@262:     //void getHead(Node& n, const Edge& e) const { n=head(e); }
deba@262: 
deba@262:     //void getANode(Node& n, const OutEdgeIt& e) const { n=e.aNode(); }
deba@262:     //void getANode(Node& n, const InEdgeIt& e) const { n=e.aNode(); }
deba@262:     //void getANode(Node& n, const SymEdgeIt& e) const { n=e.aNode(); }
deba@262:     //void getBNode(Node& n, const OutEdgeIt& e) const { n=e.bNode(); }
deba@262:     //void getBNode(Node& n, const InEdgeIt& e) const { n=e.bNode(); }
deba@262:     //void getBNode(Node& n, const SymEdgeIt& e) const { n=e.bNode(); }
deba@262:     //void get_invalid(Node& n) { n=Node(); }
deba@262:     //void get_invalid(Edge& e) { e=Edge(); }
deba@262:     //void get_invalid(OutEdgeIt& e) { e=OutEdgeIt(); }
deba@262:     //void get_invalid(InEdgeIt& e) { e=InEdgeIt(); }
deba@262:     //void get_invalid(SymEdgeIt& e) { e=SymEdgeIt(); }
deba@262: 
deba@262:     template< typename It >
deba@262:     It first() const { 
deba@262:       It e;
deba@262:       /*getF*/first(e);
deba@262:       return e; 
deba@262:     }
deba@262: 
deba@262:     template< typename It >
deba@262:     It first(Node v) const { 
deba@262:       It e;
deba@262:       /*getF*/first(e, v);
deba@262:       return e; 
deba@262:     }
deba@262: 
deba@262:     bool valid(Node n) const { return n.valid(); }
deba@262:     bool valid(Edge e) const { return e.valid(); }
deba@262:     
deba@262:     template <typename It> It getNext(It it) const { 
deba@262:       It tmp(it); return next(tmp); }
deba@262:     template <typename It> It& next(It& it) const { return ++it; }
deba@262:    
deba@262: 
deba@262:     /* for getting id's of graph objects */
deba@262:     /* these are important for the implementation of property vectors */
deba@262: 
deba@262:     int id(Node v) const { return v.node->id; }
deba@262:     int id(Edge e) const { return e.edge->id; }
deba@262: 
deba@262:     /* adding nodes and edges */
deba@262: 
deba@340:     Node addNode() { 
deba@340: 			Node n = _add_node();
deba@340: 			node_maps.add(n);
deba@340: 			return n; 
deba@340: 		}
deba@262:     Edge addEdge(Node u, Node v) {
deba@340: 			Edge e = _add_edge(u.node, v.node);
deba@340: 			edge_maps.add(e);
deba@340:       return e; 
deba@262:     }
deba@262: 
deba@262:     void erase(Node i) { 
deba@340: 			node_map.erase(i);
deba@262:       while (first<OutEdgeIt>(i).valid()) erase(first<OutEdgeIt>(i));
deba@262:       while (first<InEdgeIt>(i).valid()) erase(first<InEdgeIt>(i));
deba@262:       _delete_node(i.node); 
deba@262:     }
deba@262:   
deba@340:     void erase(Edge e) { 
deba@340: 			edge_maps.erase(e);
deba@340: 			_delete_edge(e.edge); 
deba@340: 		}
deba@262: 
deba@262:     void clear() { 
deba@262:       while (first<NodeIt>().valid()) erase(first<NodeIt>());
deba@262:     }
deba@262: 
deba@262:     void setTail(Edge e, Node tail) {
deba@262:       _set_tail(e.edge, tail.node); 
deba@262:     }
deba@262: 
deba@262:     void setHead(Edge e, Node head) {
deba@262:       _set_head(e.edge, head.node); 
deba@262:     }
deba@262: 
deba@262:     /* stream operations, for testing purpose */
deba@262: 
deba@262:     friend std::ostream& operator<<(std::ostream& os, const Node& i) { 
deba@262:       os << i.node->id; return os; 
deba@262:     }
deba@262:     friend std::ostream& operator<<(std::ostream& os, const Edge& i) { 
deba@262:       os << "(" << i.edge->_tail->id << "--" << i.edge->id << "->" << i.edge->_head->id << ")"; 
deba@262:       return os; 
deba@262:     }
deba@262: 
deba@262:     class Node {
deba@262:       friend class ListGraph;
deba@262:       template <typename T> friend class NodeMap;
deba@262: 
deba@262:       friend class Edge;
deba@262:       friend class OutEdgeIt;
deba@262:       friend class InEdgeIt;
deba@262:       friend class SymEdgeIt;
deba@262:       //public:  //FIXME: It is required by op= of NodeIt
deba@262:     protected:
deba@262:       node_item* node;
deba@262:     protected:
deba@262:       friend int ListGraph::id(Node v) const; 
deba@262:     public:
deba@262:       Node() /*: node(0)*/ { }
deba@262:       Node(const Invalid&) : node(0) { }
deba@262:     protected:
deba@262:       Node(node_item* _node) : node(_node) { }
deba@262:       bool valid() const { return (node); }
deba@262:     public:
deba@262:       //void makeInvalid() { node=0; }
deba@262:       friend bool operator==(Node u, Node v) { return v.node==u.node; } 
deba@262:       friend bool operator!=(Node u, Node v) { return v.node!=u.node; } 
deba@262:       friend std::ostream& operator<<(std::ostream& os, const Node& i);
deba@262:     };
deba@262:     
deba@262:     class NodeIt : public Node {
deba@262:       friend class ListGraph;
deba@262:       //protected:
deba@262:     public: //for everybody but marci
deba@262:       NodeIt(const ListGraph& G) : Node(G._first_node) { }
deba@262:     public:
deba@262:       NodeIt() : Node() { }
deba@262:       NodeIt(const Invalid& i) : Node(i) { }
deba@262:     protected:
deba@262:       NodeIt(node_item* v) : Node(v) { }
deba@262:       NodeIt& operator++() { node=node->_next_node; return *this; }
deba@262:       //FIXME::
deba@262:       //      NodeIt& operator=(const Node& e)
deba@262:       //      { node=e.node; return *this; }
deba@262:     };
deba@262: 
deba@262:     class Edge {
deba@262:       friend class ListGraph;
deba@262:       template <typename T> friend class EdgeMap;
deba@262:       
deba@262:       friend class Node;
deba@262:       friend class NodeIt;
deba@262:     protected:
deba@262:       edge_item* edge;
deba@262:       friend int ListGraph::id(Edge e) const;
deba@262:     public:
deba@262:       Edge() /*: edge(0)*/ { }
deba@262:       Edge(const Invalid&) : edge(0) { }
deba@262:       //Edge() { }
deba@262:     protected:
deba@262:       Edge(edge_item* _edge) : edge(_edge) { }
deba@262:       bool valid() const { return (edge); }
deba@262:     public:
deba@262:       //void makeInvalid() { edge=0; }
deba@262:       friend bool operator==(Edge u, Edge v) { return v.edge==u.edge; } 
deba@262:       friend bool operator!=(Edge u, Edge v) { return v.edge!=u.edge; } 
deba@262:     protected:
deba@262:       Node tailNode() const { return Node(edge->_tail); }
deba@262:       Node headNode() const { return Node(edge->_head); }
deba@262:     public:
deba@262:       friend std::ostream& operator<<(std::ostream& os, const Edge& i);
deba@262:     };
deba@262:     
deba@262:     class EdgeIt : public Edge {
deba@262:       friend class ListGraph;
deba@262:       //protected: 
deba@262:     public: //for alpar
deba@262:       EdgeIt(const ListGraph& G) {
deba@262: 	node_item* v=G._first_node;
deba@262: 	if (v) edge=v->_first_out_edge; else edge=0;
deba@262: 	while (v && !edge) { v=v->_next_node; if (v) edge=v->_first_out_edge; }
deba@262:       }
deba@262:     public:
deba@262:       EdgeIt() : Edge() { }
deba@262:       EdgeIt(const Invalid& i) : Edge(i) { }
deba@262:     protected:
deba@262:       EdgeIt(edge_item* _e) : Edge(_e) { }
deba@262:       EdgeIt& operator++() { 
deba@262: 	node_item* v=edge->_tail;
deba@262: 	edge=edge->_next_out; 
deba@262: 	while (v && !edge) { v=v->_next_node; if (v) edge=v->_first_out_edge; }
deba@262: 	return *this;
deba@262:       }
deba@262:     };
deba@262:     
deba@262:     class OutEdgeIt : public Edge {
deba@262:       friend class ListGraph;
deba@262:       //node_item* v;
deba@262:       //protected: 
deba@262:     protected: //for alpar
deba@262:       OutEdgeIt(const Node& _v) /*: v(_v.node)*/ { edge=_v.node->_first_out_edge; }
deba@262:     public:
deba@262:       OutEdgeIt() : Edge()/*, v(0)*/ { }
deba@262:       OutEdgeIt(const Invalid& i) : Edge(i) { }
deba@262:       OutEdgeIt(const ListGraph&, Node _v) /*: v(_v.node)*/ { edge=_v.node->_first_out_edge; }
deba@262:     protected:
deba@262:       OutEdgeIt& operator++() { edge=edge->_next_out; return *this; }
deba@262:     protected:
deba@262:       Node aNode() const { return Node(edge->_tail); }
deba@262:       Node bNode() const { return Node(edge->_head); }
deba@262:     };
deba@262:     
deba@262:     class InEdgeIt : public Edge {
deba@262:       friend class ListGraph;
deba@262:       //node_item* v;
deba@262:       //protected:
deba@262:     protected: //for alpar
deba@262:       InEdgeIt(const Node& _v) /*: v(_v.node)*/ { edge=_v.node->_first_in_edge; }
deba@262:     public:
deba@262:       InEdgeIt() : Edge()/*, v(0)*/ { }
deba@262:       InEdgeIt(const Invalid& i) : Edge(i) { }
deba@262:       InEdgeIt(const ListGraph&, Node _v) /*: v(_v.node)*/ { edge=_v.node->_first_in_edge; }
deba@262:     protected:
deba@262:       InEdgeIt& operator++() { edge=edge->_next_in; return *this; }
deba@262:     protected:
deba@262:       Node aNode() const { return Node(edge->_head); }
deba@262:       Node bNode() const { return Node(edge->_tail); }
deba@262:     };
deba@262: 
deba@262:     class SymEdgeIt : public Edge {
deba@262:       friend class ListGraph;
deba@262:       bool out_or_in; //1 iff out, 0 iff in
deba@262:       //node_item* v;
deba@262:       //protected:
deba@262:     public: //for alpar
deba@262:       SymEdgeIt(const Node& _v) /*: v(_v.node)*/ { 
deba@262: 	out_or_in=1;
deba@262: 	edge=_v.node->_first_out_edge; 
deba@262: 	if (!edge) { edge=_v.node->_first_in_edge; out_or_in=0; }
deba@262:       }
deba@262:     public:
deba@262:       SymEdgeIt() : Edge() /*, v(0)*/ { }
deba@262:       SymEdgeIt(const Invalid& i) : Edge(i) { }
deba@262:       SymEdgeIt(const ListGraph&, Node _v) /*: v(_v.node)*/ { 
deba@262: 	out_or_in=1;
deba@262: 	edge=_v.node->_first_out_edge; 
deba@262: 	if (!edge) { edge=_v.node->_first_in_edge; out_or_in=0; }
deba@262:       }
deba@262:     protected:
deba@262:       SymEdgeIt& operator++() { 
deba@262: 	if (out_or_in) { 
deba@262: 	  node_item* v=edge->_tail;
deba@262: 	  edge=edge->_next_out; 
deba@262: 	  if (!edge) { out_or_in=0; edge=v->_first_in_edge; }
deba@262: 	} else {
deba@262: 	  edge=edge->_next_in; 
deba@262: 	}
deba@262: 	return *this;
deba@262:       }
deba@262:     protected:
deba@262:       Node aNode() const { 
deba@262: 	return (out_or_in) ? Node(edge->_tail) : Node(edge->_head); }
deba@262:       Node bNode() const { 
deba@262: 	return (out_or_in) ? Node(edge->_head) : Node(edge->_tail); }
deba@262:     };
deba@262: 
deba@262:   };
deba@262: 
deba@262: //   template< typename T >
deba@262: //   T ListGraph::first() const { 
deba@262: //     std::cerr << "Invalid use of template<typemane T> T ListGraph::first<T>();" << std::endl; 
deba@262: //     return T(); 
deba@262: //   }
deba@262: 
deba@262: //   template<>
deba@262: //   ListGraph::NodeIt ListGraph::first<ListGraph::NodeIt>() const { 
deba@262: //     return firstNode(); 
deba@262: //   }
deba@262: 
deba@262: //   template<>
deba@262: //   ListGraph::EdgeIt ListGraph::first<ListGraph::EdgeIt>() const { 
deba@262: //     return firstEdge(); 
deba@262: //   }
deba@262: 
deba@262: //   template< typename T >
deba@262: //   T ListGraph::first(ListGraph::Node v) const {
deba@262: //     std::cerr << "Invalid use of template<typemane T> T ListGraph::first<T>(ListGRaph::Node);" << std::endl; 
deba@262: //     return T(); 
deba@262: //   } 
deba@262: 
deba@262: //   template<>
deba@262: //   ListGraph::OutEdgeIt ListGraph::first<ListGraph::OutEdgeIt>(const ListGraph::Node v) const { 
deba@262: //     return firstOutEdge(v); 
deba@262: //   }
deba@262: 
deba@262: //   template<>
deba@262: //   ListGraph::InEdgeIt ListGraph::first<ListGraph::InEdgeIt>(const ListGraph::Node v) const { 
deba@262: //     return firstInEdge(v); 
deba@262: //   }
deba@262: 
deba@262: //   template<>
deba@262: //   ListGraph::SymEdgeIt ListGraph::first<ListGraph::SymEdgeIt>(const ListGraph::Node v) const { 
deba@262: //     return firstSymEdge(v); 
deba@262: //   }
deba@262: 
deba@262: 
deba@262: } //namespace hugo
deba@262: 
deba@262: #endif //HUGO_LIST_GRAPH_H