marci@280: #ifndef LIST_GRAPH_HH
marci@280: #define LIST_GRAPH_HH
marci@280: 
marci@280: #include <iostream>
marci@280: #include <vector>
marci@280: 
marci@280: namespace hugo {
marci@280: 
marci@280:   template <typename It>
marci@280:   int count(It it) { 
marci@280:     int i=0;
marci@280:     for( ; it.valid(); ++it) { ++i; } 
marci@280:     return i;
marci@280:   }
marci@280: 
marci@280:   class ListGraph {
marci@280: 
marci@280:     class node_item;
marci@280:     class edge_item;
marci@280: 
marci@280:   public:
marci@280: 
marci@280:     class NodeIt;
marci@280:     class EachNodeIt;
marci@280:     class EdgeIt;
marci@280:     class EachEdgeIt;
marci@280:     class OutEdgeIt;
marci@280:     class InEdgeIt;
marci@280:     class SymEdgeIt;
marci@280:     template <typename T> class NodeMap;
marci@280:     template <typename T> class EdgeMap;
marci@280:     
marci@280:   private:
marci@280:     
marci@280:     template <typename T> friend class NodeMap;
marci@280:     template <typename T> friend class EdgeMap;
marci@280: 
marci@280:     template <typename T>
marci@280:     class NodeMap {
marci@280:       const ListGraph& G; 
marci@280:       std::vector<T> container;
marci@280:     public:
marci@280:       typedef T ValueType;
marci@280:       typedef NodeIt KeyType;
marci@280:       NodeMap(const ListGraph& _G) : G(_G), container(G.node_id) { }
marci@280:       NodeMap(const ListGraph& _G, T a) : 
marci@280: 	G(_G), container(G.node_id, a) { }
marci@280:       void set(NodeIt n, T a) { container[/*G.id(n)*/n.node->id]=a; }
marci@280:       T get(NodeIt n) const { return container[/*G.id(n)*/n.node->id]; }
marci@280:       T& operator[](NodeIt n) { return container[/*G.id(n)*/n.node->id]; }
marci@280:       const T& operator[](NodeIt n) const { return container[/*G.id(n)*/n.node->id]; }
marci@280:       void update() { container.resize(G.node_id); }
marci@280:       void update(T a) { container.resize(G.node_id, a); }
marci@280:     };
marci@280: 
marci@280:     template <typename T>
marci@280:     class EdgeMap {
marci@280:       const ListGraph& G; 
marci@280:       std::vector<T> container;
marci@280:     public:
marci@280:       typedef T ValueType;
marci@280:       typedef EdgeIt KeyType;
marci@280:       EdgeMap(const ListGraph& _G) : G(_G), container(G.edge_id) { }
marci@280:       EdgeMap(const ListGraph& _G, T a) : 
marci@280: 	G(_G), container(G.edge_id, a) { }
marci@280:       void set(EdgeIt e, T a) { container[/*G.id(e)*/e.edge->id]=a; }
marci@280:       T get(EdgeIt e) const { return container[/*G.id(e)*/e.edge->id]; }
marci@280:       T& operator[](EdgeIt e) { return container[/*G.id(e)*/e.edge->id]; } 
marci@280:       const T& operator[](EdgeIt e) const { return container[/*G.id(e)*/e.edge->id]; } 
marci@280:       void update() { container.resize(G.edge_id); }
marci@280:       void update(T a) { container.resize(G.edge_id, a); }
marci@280:     };
marci@280: 
marci@280:     int node_id;
marci@280:     int edge_id;
marci@280:     int _node_num;
marci@280:     int _edge_num;
marci@280: 
marci@280:     node_item* _first_node;
marci@280:     node_item* _last_node;
marci@280: 
marci@280:     class node_item {
marci@280:       friend class ListGraph;
marci@280:       template <typename T> friend class NodeMap;
marci@280:       
marci@280:       friend class NodeIt;
marci@280:       friend class EachNodeIt;
marci@280:       friend class EdgeIt;
marci@280:       friend class EachEdgeIt;
marci@280:       friend class OutEdgeIt;
marci@280:       friend class InEdgeIt;
marci@280:       friend class SymEdgeIt;
marci@280:       friend std::ostream& operator<<(std::ostream& os, const NodeIt& i);
marci@280:       friend std::ostream& operator<<(std::ostream& os, const EdgeIt& i);
marci@280:       //ListGraph* G;
marci@280:       int id;
marci@280:       edge_item* _first_out_edge;
marci@280:       edge_item* _last_out_edge;
marci@280:       edge_item* _first_in_edge;
marci@280:       edge_item* _last_in_edge;
marci@280:       node_item* _next_node;
marci@280:       node_item* _prev_node;
marci@280:     public:
marci@280:       node_item() { }
marci@280:     };
marci@280: 
marci@280:     class edge_item {
marci@280:       friend class ListGraph;
marci@280:       template <typename T> friend class EdgeMap;
marci@280: 
marci@280:       friend class NodeIt;
marci@280:       friend class EachNodeIt;
marci@280:       friend class EdgeIt;
marci@280:       friend class EachEdgeIt;
marci@280:       friend class OutEdgeIt;
marci@280:       friend class InEdgeIt;
marci@280:       friend class SymEdgeIt;
marci@280:       friend std::ostream& operator<<(std::ostream& os, const EdgeIt& i);
marci@280:       //ListGraph* G;
marci@280:       int id;
marci@280:       node_item* _tail;
marci@280:       node_item* _head;
marci@280:       edge_item* _next_out;
marci@280:       edge_item* _prev_out;
marci@280:       edge_item* _next_in;
marci@280:       edge_item* _prev_in;
marci@280:     public:
marci@280:       edge_item() { }
marci@280:     };
marci@280: 
marci@280:     node_item* _add_node() { 
marci@280:       node_item* p=new node_item;
marci@280:       p->id=node_id++;
marci@280:       p->_first_out_edge=0;
marci@280:       p->_last_out_edge=0;
marci@280:       p->_first_in_edge=0;
marci@280:       p->_last_in_edge=0;
marci@280:       p->_prev_node=_last_node;
marci@280:       p->_next_node=0;
marci@280:       if (_last_node) _last_node->_next_node=p;
marci@280:       _last_node=p;
marci@280:       if (!_first_node) _first_node=p;
marci@280: 
marci@280:       ++_node_num;
marci@280:       return p;
marci@280:     }
marci@280: 
marci@280:     edge_item* _add_edge(node_item* _tail, node_item* _head) {
marci@280:       edge_item* e=new edge_item;
marci@280:       e->id=edge_id++;
marci@280:       e->_tail=_tail;
marci@280:       e->_head=_head;
marci@280:       
marci@280:       e->_prev_out=_tail->_last_out_edge;
marci@280:       if (_tail->_last_out_edge) (_tail->_last_out_edge)->_next_out=e;
marci@280:       _tail->_last_out_edge=e;
marci@280:       if (!_tail->_first_out_edge) _tail->_first_out_edge=e; 
marci@280:       e->_next_out=0;
marci@280:  
marci@280:       e->_prev_in=_head->_last_in_edge;
marci@280:       if (_head->_last_in_edge) (_head->_last_in_edge)->_next_in=e;
marci@280:       _head->_last_in_edge=e;
marci@280:       if (!_head->_first_in_edge) { _head->_first_in_edge=e; } 
marci@280:       e->_next_in=0;
marci@280: 
marci@280:       ++_edge_num;
marci@280:       return e;
marci@280:     }
marci@280: 
marci@280:     //deletes a node which has no out edge and no in edge
marci@280:     void _delete_node(node_item* v) {
marci@280:       if (v->_next_node) (v->_next_node)->_prev_node=v->_prev_node; else 
marci@280: 	_last_node=v->_prev_node;
marci@280:       if (v->_prev_node) (v->_prev_node)->_next_node=v->_next_node; else 
marci@280: 	_first_node=v->_next_node;
marci@280: 
marci@280:       delete v;
marci@280:       --_node_num;
marci@280:     }
marci@280: 
marci@280:     void _delete_edge(edge_item* e) {
marci@280:       if (e->_next_out) (e->_next_out)->_prev_out=e->_prev_out; else 
marci@280: 	(e->_tail)->_last_out_edge=e->_prev_out;
marci@280:       if (e->_prev_out) (e->_prev_out)->_next_out=e->_next_out; else 
marci@280: 	(e->_tail)->_first_out_edge=e->_next_out;
marci@280:       if (e->_next_in) (e->_next_in)->_prev_in=e->_prev_in; else 
marci@280: 	(e->_head)->_last_in_edge=e->_prev_in;
marci@280:       if (e->_prev_in) (e->_prev_in)->_next_in=e->_next_in; else 
marci@280: 	(e->_head)->_first_in_edge=e->_next_in;
marci@280: 
marci@280:       delete e;
marci@280:       --_edge_num;
marci@280:     }
marci@280: 
marci@280:     void _set_tail(edge_item* e, node_item* _tail) {
marci@280:       if (e->_next_out) (e->_next_out)->_prev_out=e->_prev_out; else 
marci@280: 	(e->_tail)->_last_out_edge=e->_prev_out;
marci@280:       if (e->_prev_out) (e->_prev_out)->_next_out=e->_next_out; else 
marci@280: 	(e->_tail)->_first_out_edge=e->_next_out;
marci@280:       
marci@280:       e->_tail=_tail;
marci@280:       
marci@280:       e->_prev_out=_tail->_last_out_edge;
marci@280:       if (_tail->_last_out_edge) (_tail->_last_out_edge)->_next_out=e;
marci@280:       _tail->_last_out_edge=e;
marci@280:       if (!_tail->_first_out_edge) _tail->_first_out_edge=e; 
marci@280:       e->_next_out=0;
marci@280:     }
marci@280: 
marci@280:     void _set_head(edge_item* e, node_item* _head) {
marci@280:       if (e->_next_in) (e->_next_in)->_prev_in=e->_prev_in; else 
marci@280: 	(e->_head)->_last_in_edge=e->_prev_in;
marci@280:       if (e->_prev_in) (e->_prev_in)->_next_in=e->_next_in; else 
marci@280: 	(e->_head)->_first_in_edge=e->_next_in;
marci@280:       
marci@280:       e->_head=_head;
marci@280:       
marci@280:       e->_prev_in=_head->_last_in_edge;
marci@280:       if (_head->_last_in_edge) (_head->_last_in_edge)->_next_in=e;
marci@280:       _head->_last_in_edge=e;
marci@280:       if (!_head->_first_in_edge) { _head->_first_in_edge=e; } 
marci@280:       e->_next_in=0;
marci@280:     }
marci@280: 
marci@280:   public:
marci@280: 
marci@280:     /* default constructor */
marci@280: 
marci@280:     ListGraph() : node_id(0), edge_id(0), _node_num(0), _edge_num(0), _first_node(0), _last_node(0) { }
marci@280:     
marci@280:     ~ListGraph() { 
marci@280:       while (first<EachNodeIt>().valid()) erase(first<EachNodeIt>());
marci@280:     }
marci@280: 
marci@280:     int nodeNum() const { return _node_num; }
marci@280:     int edgeNum() const { return _edge_num; }
marci@280: 
marci@280:     /* functions to construct iterators from the graph, or from each other */
marci@280: 
marci@280:     //EachNodeIt firstNode() const { return EachNodeIt(*this); }
marci@280:     //EachEdgeIt firstEdge() const { return EachEdgeIt(*this); }
marci@280:     
marci@280:     //OutEdgeIt firstOutEdge(const NodeIt v) const { return OutEdgeIt(v); }
marci@280:     //InEdgeIt firstInEdge(const NodeIt v) const { return InEdgeIt(v); }
marci@280:     //SymEdgeIt firstSymEdge(const NodeIt v) const { return SymEdgeIt(v); }
marci@280:     NodeIt tail(EdgeIt e) const { return e.tailNode(); }
marci@280:     NodeIt head(EdgeIt e) const { return e.headNode(); }
marci@280: 
marci@280:     NodeIt aNode(const OutEdgeIt& e) const { return e.aNode(); }
marci@280:     NodeIt aNode(const InEdgeIt& e) const { return e.aNode(); }
marci@280:     NodeIt aNode(const SymEdgeIt& e) const { return e.aNode(); }
marci@280: 
marci@280:     NodeIt bNode(const OutEdgeIt& e) const { return e.bNode(); }
marci@280:     NodeIt bNode(const InEdgeIt& e) const { return e.bNode(); }
marci@280:     NodeIt bNode(const SymEdgeIt& e) const { return e.bNode(); }
marci@280: 
marci@280:     //NodeIt invalid_node() { return NodeIt(); }
marci@280:     //EdgeIt invalid_edge() { return EdgeIt(); }
marci@280:     //OutEdgeIt invalid_out_edge() { return OutEdgeIt(); }
marci@280:     //InEdgeIt invalid_in_edge() { return InEdgeIt(); }
marci@280:     //SymEdgeIt invalid_sym_edge() { return SymEdgeIt(); }
marci@280: 
marci@280:     /* same methods in other style */
marci@280:     /* for experimental purpose */
marci@280: 
marci@280:     EachNodeIt& getFirst(EachNodeIt& v) const { 
marci@280:       v=EachNodeIt(*this); return v; }
marci@280:     EachEdgeIt& getFirst(EachEdgeIt& e) const { 
marci@280:       e=EachEdgeIt(*this); return e; }
marci@280:     OutEdgeIt& getFirst(OutEdgeIt& e, NodeIt v) const { 
marci@280:       e=OutEdgeIt(v); return e; }
marci@280:     InEdgeIt& getFirst(InEdgeIt& e, NodeIt v) const { 
marci@280:       e=InEdgeIt(v); return e; }
marci@280:     SymEdgeIt& getFirst(SymEdgeIt& e, NodeIt v) const { 
marci@280:       e=SymEdgeIt(v); return e; }
marci@280:     //void getTail(NodeIt& n, const EdgeIt& e) const { n=tail(e); }
marci@280:     //void getHead(NodeIt& n, const EdgeIt& e) const { n=head(e); }
marci@280: 
marci@280:     //void getANode(NodeIt& n, const OutEdgeIt& e) const { n=e.aNode(); }
marci@280:     //void getANode(NodeIt& n, const InEdgeIt& e) const { n=e.aNode(); }
marci@280:     //void getANode(NodeIt& n, const SymEdgeIt& e) const { n=e.aNode(); }
marci@280:     //void getBNode(NodeIt& n, const OutEdgeIt& e) const { n=e.bNode(); }
marci@280:     //void getBNode(NodeIt& n, const InEdgeIt& e) const { n=e.bNode(); }
marci@280:     //void getBNode(NodeIt& n, const SymEdgeIt& e) const { n=e.bNode(); }
marci@280:     //void get_invalid(NodeIt& n) { n=NodeIt(); }
marci@280:     //void get_invalid(EdgeIt& e) { e=EdgeIt(); }
marci@280:     //void get_invalid(OutEdgeIt& e) { e=OutEdgeIt(); }
marci@280:     //void get_invalid(InEdgeIt& e) { e=InEdgeIt(); }
marci@280:     //void get_invalid(SymEdgeIt& e) { e=SymEdgeIt(); }
marci@280: 
marci@280:     template< typename It >
marci@280:     It first() const { 
marci@280:       It e;
marci@280:       getFirst(e);
marci@280:       return e; 
marci@280:     }
marci@280: 
marci@280:     template< typename It >
marci@280:     It first(NodeIt v) const { 
marci@280:       It e;
marci@280:       getFirst(e, v);
marci@280:       return e; 
marci@280:     }
marci@280: 
marci@280:     bool valid(NodeIt n) const { return n.valid(); }
marci@280:     bool valid(EdgeIt e) const { return e.valid(); }
marci@280:     
marci@280:     template <typename It> It getNext(It it) const { 
marci@280:       It tmp(it); return next(tmp); }
marci@280:     template <typename It> It& next(It& it) const { return ++it; }
marci@280:    
marci@280: 
marci@280:     /* for getting id's of graph objects */
marci@280:     /* these are important for the implementation of property vectors */
marci@280: 
marci@280:     int id(NodeIt v) const { return v.node->id; }
marci@280:     int id(EdgeIt e) const { return e.edge->id; }
marci@280: 
marci@280:     /* adding nodes and edges */
marci@280: 
marci@280:     NodeIt addNode() { return NodeIt(_add_node()); }
marci@280:     EdgeIt addEdge(NodeIt u, NodeIt v) {
marci@280:       return EdgeIt(_add_edge(u.node, v.node)); 
marci@280:     }
marci@280: 
marci@280:     void erase(NodeIt i) { 
marci@280:       while (first<OutEdgeIt>(i).valid()) erase(first<OutEdgeIt>(i));
marci@280:       while (first<InEdgeIt>(i).valid()) erase(first<InEdgeIt>(i));
marci@280:       _delete_node(i.node); 
marci@280:     }
marci@280:   
marci@280:     void erase(EdgeIt e) { _delete_edge(e.edge); }
marci@280: 
marci@280:     void clear() { 
marci@280:       while (first<EachNodeIt>().valid()) erase(first<EachNodeIt>());
marci@280:     }
marci@280: 
marci@280:     void setTail(EdgeIt e, NodeIt tail) {
marci@280:       _set_tail(e.edge, tail.node); 
marci@280:     }
marci@280: 
marci@280:     void setHead(EdgeIt e, NodeIt head) {
marci@280:       _set_head(e.edge, head.node); 
marci@280:     }
marci@280: 
marci@280:     /* stream operations, for testing purpose */
marci@280: 
marci@280:     friend std::ostream& operator<<(std::ostream& os, const NodeIt& i) { 
marci@280:       os << i.node->id; return os; 
marci@280:     }
marci@280:     friend std::ostream& operator<<(std::ostream& os, const EdgeIt& i) { 
marci@280:       os << "(" << i.edge->_tail->id << "--" << i.edge->id << "->" << i.edge->_head->id << ")"; 
marci@280:       return os; 
marci@280:     }
marci@280: 
marci@280:     class NodeIt {
marci@280:       friend class ListGraph;
marci@280:       template <typename T> friend class NodeMap;
marci@280: 
marci@280:       friend class EdgeIt;
marci@280:       friend class OutEdgeIt;
marci@280:       friend class InEdgeIt;
marci@280:       friend class SymEdgeIt;
marci@280:       //public:  //FIXME: It is required by op= of EachNodeIt
marci@280:     protected:
marci@280:       node_item* node;
marci@280:     protected:
marci@280:       friend int ListGraph::id(NodeIt v) const; 
marci@280:     public:
marci@280:       NodeIt() : node(0) { }
marci@280:       NodeIt(node_item* _node) : node(_node) { }
marci@280:       bool valid() const { return (node!=0); }
marci@280:       //void makeInvalid() { node=0; }
marci@280:       friend bool operator==(const NodeIt& u, const NodeIt& v) { 
marci@280: 	return v.node==u.node; 
marci@280:       } 
marci@280:       friend bool operator!=(const NodeIt& u, const NodeIt& v) { 
marci@280: 	return v.node!=u.node; 
marci@280:       } 
marci@280:       friend std::ostream& operator<<(std::ostream& os, const NodeIt& i);
marci@280:     };
marci@280:     
marci@280:     class EachNodeIt : public NodeIt {
marci@280:       friend class ListGraph;
marci@280:       //protected:
marci@280:     public: //for everybody but marci
marci@280:       EachNodeIt(const ListGraph& G) : NodeIt(G._first_node) { }
marci@280:     public:
marci@280:       EachNodeIt() : NodeIt() { }
marci@280:       EachNodeIt(node_item* v) : NodeIt(v) { }
marci@280:       EachNodeIt& operator++() { node=node->_next_node; return *this; }
marci@280:       //FIXME::
marci@280:       //      EachNodeIt& operator=(const NodeIt& e)
marci@280:       //      { node=e.node; return *this; }
marci@280:     };
marci@280: 
marci@280:     class EdgeIt {
marci@280:       friend class ListGraph;
marci@280:       template <typename T> friend class EdgeMap;
marci@280:       
marci@280:       friend class NodeIt;
marci@280:       friend class EachNodeIt;
marci@280:     protected:
marci@280:       edge_item* edge;
marci@280:       friend int ListGraph::id(EdgeIt e) const;
marci@280:     public:
marci@280:       EdgeIt() : edge(0) { }
marci@280:       //EdgeIt() { }
marci@280:       EdgeIt(edge_item* _edge) : edge(_edge) { }
marci@280:       bool valid() const { return (edge!=0); }
marci@280:       //void makeInvalid() { edge=0; }
marci@280:       friend bool operator==(const EdgeIt& u, const EdgeIt& v) { 
marci@280: 	return v.edge==u.edge; 
marci@280:       } 
marci@280:       friend bool operator!=(const EdgeIt& u, const EdgeIt& v) { 
marci@280: 	return v.edge!=u.edge; 
marci@280:       } 
marci@280:     protected:
marci@280:       NodeIt tailNode() const { return NodeIt(edge->_tail); }
marci@280:       NodeIt headNode() const { return NodeIt(edge->_head); }
marci@280:     public:
marci@280:       friend std::ostream& operator<<(std::ostream& os, const EdgeIt& i);
marci@280:     };
marci@280:     
marci@280:     class EachEdgeIt : public EdgeIt {
marci@280:       friend class ListGraph;
marci@280:       //protected: 
marci@280:     public: //for alpar
marci@280:       EachEdgeIt(const ListGraph& G) {
marci@280: 	node_item* v=G._first_node;
marci@280: 	if (v) edge=v->_first_out_edge; else edge=0;
marci@280: 	while (v && !edge) { v=v->_next_node; if (v) edge=v->_first_out_edge; }
marci@280:       }
marci@280:     public:
marci@280:       EachEdgeIt() : EdgeIt() { }
marci@280:       EachEdgeIt(edge_item* _e) : EdgeIt(_e) { }
marci@280:       EachEdgeIt& operator++() { 
marci@280: 	node_item* v=edge->_tail;
marci@280: 	edge=edge->_next_out; 
marci@280: 	while (v && !edge) { v=v->_next_node; if (v) edge=v->_first_out_edge; }
marci@280: 	return *this;
marci@280:       }
marci@280:     };
marci@280:     
marci@280:     class OutEdgeIt : public EdgeIt {
marci@280:       friend class ListGraph;
marci@280:       //node_item* v;
marci@280:       //protected: 
marci@280:     public: //for alpar
marci@280:       OutEdgeIt(const NodeIt& _v) /*: v(_v.node)*/ { edge=_v.node->_first_out_edge; }
marci@280:     public:
marci@280:       OutEdgeIt() : EdgeIt()/*, v(0)*/ { }
marci@280:       OutEdgeIt(const ListGraph& G, NodeIt _v) /*: v(_v.node)*/ { edge=_v.node->_first_out_edge; }
marci@280:       OutEdgeIt& operator++() { edge=edge->_next_out; return *this; }
marci@280:     protected:
marci@280:       NodeIt aNode() const { return NodeIt(edge->_tail); }
marci@280:       NodeIt bNode() const { return NodeIt(edge->_head); }
marci@280:     };
marci@280:     
marci@280:     class InEdgeIt : public EdgeIt {
marci@280:       friend class ListGraph;
marci@280:       //node_item* v;
marci@280:       //protected:
marci@280:     public: //for alpar
marci@280:       InEdgeIt(const NodeIt& _v) /*: v(_v.node)*/ { edge=_v.node->_first_in_edge; }
marci@280:     public:
marci@280:       InEdgeIt() : EdgeIt()/*, v(0)*/ { }
marci@280:       InEdgeIt(const ListGraph& G, NodeIt _v) /*: v(_v.node)*/ { edge=_v.node->_first_in_edge; }
marci@280:       InEdgeIt& operator++() { edge=edge->_next_in; return *this; }
marci@280:     protected:
marci@280:       NodeIt aNode() const { return NodeIt(edge->_head); }
marci@280:       NodeIt bNode() const { return NodeIt(edge->_tail); }
marci@280:     };
marci@280: 
marci@280:     class SymEdgeIt : public EdgeIt {
marci@280:       friend class ListGraph;
marci@280:       bool out_or_in; //1 iff out, 0 iff in
marci@280:       //node_item* v;
marci@280:       //protected:
marci@280:     public: //for alpar
marci@280:       SymEdgeIt(const NodeIt& _v) /*: v(_v.node)*/ { 
marci@280: 	out_or_in=1;
marci@280: 	edge=_v.node->_first_out_edge; 
marci@280: 	if (!edge) { edge=_v.node->_first_in_edge; out_or_in=0; }
marci@280:       }
marci@280:     public:
marci@280:       SymEdgeIt() : EdgeIt() /*, v(0)*/ { }
marci@280:       SymEdgeIt(const ListGraph& G, NodeIt _v) /*: v(_v.node)*/ { 
marci@280: 	out_or_in=1;
marci@280: 	edge=_v.node->_first_out_edge; 
marci@280: 	if (!edge) { edge=_v.node->_first_in_edge; out_or_in=0; }
marci@280:       }
marci@280:       SymEdgeIt& operator++() { 
marci@280: 	if (out_or_in) { 
marci@280: 	  node_item* v=edge->_tail;
marci@280: 	  edge=edge->_next_out; 
marci@280: 	  if (!edge) { out_or_in=0; edge=v->_first_in_edge; }
marci@280: 	} else {
marci@280: 	  edge=edge->_next_in; 
marci@280: 	}
marci@280: 	return *this;
marci@280:       }
marci@280:     protected:
marci@280:       NodeIt aNode() const { 
marci@280: 	return (out_or_in) ? NodeIt(edge->_tail) : NodeIt(edge->_head); }
marci@280:       NodeIt bNode() const { 
marci@280: 	return (out_or_in) ? NodeIt(edge->_head) : NodeIt(edge->_tail); }
marci@280:     };
marci@280: 
marci@280:   };
marci@280: 
marci@280: //   template< typename T >
marci@280: //   T ListGraph::first() const { 
marci@280: //     std::cerr << "Invalid use of template<typemane T> T ListGraph::first<T>();" << std::endl; 
marci@280: //     return T(); 
marci@280: //   }
marci@280: 
marci@280: //   template<>
marci@280: //   ListGraph::EachNodeIt ListGraph::first<ListGraph::EachNodeIt>() const { 
marci@280: //     return firstNode(); 
marci@280: //   }
marci@280: 
marci@280: //   template<>
marci@280: //   ListGraph::EachEdgeIt ListGraph::first<ListGraph::EachEdgeIt>() const { 
marci@280: //     return firstEdge(); 
marci@280: //   }
marci@280: 
marci@280: //   template< typename T >
marci@280: //   T ListGraph::first(ListGraph::NodeIt v) const {
marci@280: //     std::cerr << "Invalid use of template<typemane T> T ListGraph::first<T>(ListGRaph::NodeIt);" << std::endl; 
marci@280: //     return T(); 
marci@280: //   } 
marci@280: 
marci@280: //   template<>
marci@280: //   ListGraph::OutEdgeIt ListGraph::first<ListGraph::OutEdgeIt>(const ListGraph::NodeIt v) const { 
marci@280: //     return firstOutEdge(v); 
marci@280: //   }
marci@280: 
marci@280: //   template<>
marci@280: //   ListGraph::InEdgeIt ListGraph::first<ListGraph::InEdgeIt>(const ListGraph::NodeIt v) const { 
marci@280: //     return firstInEdge(v); 
marci@280: //   }
marci@280: 
marci@280: //   template<>
marci@280: //   ListGraph::SymEdgeIt ListGraph::first<ListGraph::SymEdgeIt>(const ListGraph::NodeIt v) const { 
marci@280: //     return firstSymEdge(v); 
marci@280: //   }
marci@280: 
marci@280: 
marci@280: } //namespace hugo
marci@280: 
marci@280: #endif //LIST_GRAPH_HH