src/lemon/graph_wrapper.h
changeset 942 75fdd0c6866d
parent 932 ade3cdb9b45d
child 970 09f9abe22df2
equal deleted inserted replaced
3:07c24e1d5af5 4:2dc4ea021230
   366   1
   366   1
   367   \endcode
   367   \endcode
   368   Note that \c n is of type \c SubGW::NodeIt, but it can be converted to
   368   Note that \c n is of type \c SubGW::NodeIt, but it can be converted to
   369   \c Graph::Node that is why \c g.id(n) can be applied.
   369   \c Graph::Node that is why \c g.id(n) can be applied.
   370 
   370 
   371   Consider now a mathematically more invloved problem, where the application 
   371   For other examples see also the documentation of NodeSubGraphWrapper and 
   372   of SubGraphWrapper is reasonable sure enough. If a shortest path is to be 
   372   EdgeSubGraphWrapper.
       
   373 
       
   374   \author Marton Makai
       
   375   */
       
   376   template<typename Graph, typename NodeFilterMap, 
       
   377 	   typename EdgeFilterMap>
       
   378   class SubGraphWrapper : public GraphWrapper<Graph> {
       
   379   public:
       
   380     typedef GraphWrapper<Graph> Parent;
       
   381   protected:
       
   382     NodeFilterMap* node_filter_map;
       
   383     EdgeFilterMap* edge_filter_map;
       
   384 
       
   385     SubGraphWrapper() : GraphWrapper<Graph>(), 
       
   386 			node_filter_map(0), edge_filter_map(0) { }
       
   387     void setNodeFilterMap(NodeFilterMap& _node_filter_map) {
       
   388       node_filter_map=&_node_filter_map;
       
   389     }
       
   390     void setEdgeFilterMap(EdgeFilterMap& _edge_filter_map) {
       
   391       edge_filter_map=&_edge_filter_map;
       
   392     }
       
   393     
       
   394   public:
       
   395     SubGraphWrapper(Graph& _graph, NodeFilterMap& _node_filter_map, 
       
   396 		    EdgeFilterMap& _edge_filter_map) : 
       
   397       GraphWrapper<Graph>(_graph), node_filter_map(&_node_filter_map), 
       
   398       edge_filter_map(&_edge_filter_map) { }  
       
   399 
       
   400     typedef typename GraphWrapper<Graph>::Node Node;
       
   401     class NodeIt : public Node { 
       
   402       const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>* gw;
       
   403       friend class SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>;
       
   404     public:
       
   405       NodeIt() { }
       
   406       NodeIt(Invalid i) : Node(i) { }
       
   407       NodeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw) : 
       
   408 	Node(typename Graph::NodeIt(*(_gw.graph))), gw(&_gw) { 
       
   409 	while (*static_cast<Node*>(this)!=INVALID && 
       
   410 	       !(*(gw->node_filter_map))[*this]) 
       
   411 	  *(static_cast<Node*>(this))=
       
   412 	    ++(typename Graph::NodeIt(*(gw->graph), *this));
       
   413       }
       
   414       NodeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw, 
       
   415 	     const Node& n) : 
       
   416 	Node(n), gw(&_gw) { }
       
   417       NodeIt& operator++() { 
       
   418 	*(static_cast<Node*>(this))=
       
   419 	  ++(typename Graph::NodeIt(*(gw->graph), *this));
       
   420 	while (*static_cast<Node*>(this)!=INVALID && 
       
   421 	       !(*(gw->node_filter_map))[*this]) 
       
   422 	  *(static_cast<Node*>(this))=
       
   423 	    ++(typename Graph::NodeIt(*(gw->graph), *this));
       
   424 	return *this; 
       
   425       }
       
   426     };
       
   427     typedef typename GraphWrapper<Graph>::Edge Edge;
       
   428     class OutEdgeIt : public Edge { 
       
   429       const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>* gw;
       
   430       friend class SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>;
       
   431     public:
       
   432       OutEdgeIt() { }
       
   433       OutEdgeIt(Invalid i) : Edge(i) { }
       
   434       OutEdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw, const Node& n) : 
       
   435 	Edge(typename Graph::OutEdgeIt(*(_gw.graph), n)), gw(&_gw) { 
       
   436 	while (*static_cast<Edge*>(this)!=INVALID && 
       
   437 	       !(*(gw->edge_filter_map))[*this]) 
       
   438 	  *(static_cast<Edge*>(this))=
       
   439 	    ++(typename Graph::OutEdgeIt(*(gw->graph), *this));
       
   440       }
       
   441       OutEdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw, 
       
   442 	     const Edge& e) : 
       
   443 	Edge(e), gw(&_gw) { }
       
   444       OutEdgeIt& operator++() { 
       
   445 	*(static_cast<Edge*>(this))=
       
   446 	  ++(typename Graph::OutEdgeIt(*(gw->graph), *this));
       
   447 	while (*static_cast<Edge*>(this)!=INVALID && 
       
   448 	       !(*(gw->edge_filter_map))[*this]) 
       
   449 	  *(static_cast<Edge*>(this))=
       
   450 	    ++(typename Graph::OutEdgeIt(*(gw->graph), *this));
       
   451 	return *this; 
       
   452       }
       
   453     };
       
   454     class InEdgeIt : public Edge { 
       
   455       const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>* gw;
       
   456       friend class SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>;
       
   457     public:
       
   458       InEdgeIt() { }
       
   459       //      InEdgeIt(const InEdgeIt& e) : Edge(e), gw(e.gw) { }
       
   460       InEdgeIt(Invalid i) : Edge(i) { }
       
   461       InEdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw, const Node& n) : 
       
   462 	Edge(typename Graph::InEdgeIt(*(_gw.graph), n)), gw(&_gw) { 
       
   463 	while (*static_cast<Edge*>(this)!=INVALID && 
       
   464 	       !(*(gw->edge_filter_map))[*this]) 
       
   465 	  *(static_cast<Edge*>(this))=
       
   466 	    ++(typename Graph::InEdgeIt(*(gw->graph), *this));
       
   467       }
       
   468       InEdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw, 
       
   469 	     const Edge& e) : 
       
   470 	Edge(e), gw(&_gw) { }
       
   471       InEdgeIt& operator++() { 
       
   472 	*(static_cast<Edge*>(this))=
       
   473 	  ++(typename Graph::InEdgeIt(*(gw->graph), *this));
       
   474 	while (*static_cast<Edge*>(this)!=INVALID && 
       
   475 	       !(*(gw->edge_filter_map))[*this]) 
       
   476 	  *(static_cast<Edge*>(this))=
       
   477 	    ++(typename Graph::InEdgeIt(*(gw->graph), *this));
       
   478 	return *this; 
       
   479       }
       
   480     };
       
   481     class EdgeIt : public Edge { 
       
   482       const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>* gw;
       
   483       friend class SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>;
       
   484     public:
       
   485       EdgeIt() { }
       
   486       EdgeIt(Invalid i) : Edge(i) { }
       
   487       EdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw) : 
       
   488 	Edge(typename Graph::EdgeIt(*(_gw.graph))), gw(&_gw) { 
       
   489 	while (*static_cast<Edge*>(this)!=INVALID && 
       
   490 	       !(*(gw->edge_filter_map))[*this]) 
       
   491 	  *(static_cast<Edge*>(this))=
       
   492 	    ++(typename Graph::EdgeIt(*(gw->graph), *this));
       
   493       }
       
   494       EdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw, 
       
   495 	     const Edge& e) : 
       
   496 	Edge(e), gw(&_gw) { }
       
   497       EdgeIt& operator++() { 
       
   498 	*(static_cast<Edge*>(this))=
       
   499 	  ++(typename Graph::EdgeIt(*(gw->graph), *this));
       
   500 	while (*static_cast<Edge*>(this)!=INVALID && 
       
   501 	       !(*(gw->edge_filter_map))[*this]) 
       
   502 	  *(static_cast<Edge*>(this))=
       
   503 	    ++(typename Graph::EdgeIt(*(gw->graph), *this));
       
   504 	return *this; 
       
   505       }
       
   506     };
       
   507 
       
   508     NodeIt& first(NodeIt& i) const { 
       
   509       i=NodeIt(*this); return i;
       
   510     }
       
   511     OutEdgeIt& first(OutEdgeIt& i, const Node& p) const { 
       
   512       i=OutEdgeIt(*this, p); return i;
       
   513     }
       
   514     InEdgeIt& first(InEdgeIt& i, const Node& p) const { 
       
   515       i=InEdgeIt(*this, p); return i;
       
   516     }
       
   517     EdgeIt& first(EdgeIt& i) const { 
       
   518       i=EdgeIt(*this); return i;
       
   519     }
       
   520     
       
   521     /// This function hides \c n in the graph, i.e. the iteration 
       
   522     /// jumps over it. This is done by simply setting the value of \c n  
       
   523     /// to be false in the corresponding node-map.
       
   524     void hide(const Node& n) const { node_filter_map->set(n, false); }
       
   525 
       
   526     /// This function hides \c e in the graph, i.e. the iteration 
       
   527     /// jumps over it. This is done by simply setting the value of \c e  
       
   528     /// to be false in the corresponding edge-map.
       
   529     void hide(const Edge& e) const { edge_filter_map->set(e, false); }
       
   530 
       
   531     /// The value of \c n is set to be true in the node-map which stores 
       
   532     /// hide information. If \c n was hidden previuosly, then it is shown 
       
   533     /// again
       
   534      void unHide(const Node& n) const { node_filter_map->set(n, true); }
       
   535 
       
   536     /// The value of \c e is set to be true in the edge-map which stores 
       
   537     /// hide information. If \c e was hidden previuosly, then it is shown 
       
   538     /// again
       
   539     void unHide(const Edge& e) const { edge_filter_map->set(e, true); }
       
   540 
       
   541     /// Returns true if \c n is hidden.
       
   542     bool hidden(const Node& n) const { return !(*node_filter_map)[n]; }
       
   543 
       
   544     /// Returns true if \c n is hidden.
       
   545     bool hidden(const Edge& e) const { return !(*edge_filter_map)[e]; }
       
   546 
       
   547     /// \warning This is a linear time operation and works only if 
       
   548     /// \c Graph::NodeIt is defined.
       
   549     int nodeNum() const { 
       
   550       int i=0;
       
   551       for (NodeIt n(*this); n!=INVALID; ++n) ++i;
       
   552       return i; 
       
   553     }
       
   554 
       
   555     /// \warning This is a linear time operation and works only if 
       
   556     /// \c Graph::EdgeIt is defined.
       
   557     int edgeNum() const { 
       
   558       int i=0;
       
   559       for (EdgeIt e(*this); e!=INVALID; ++e) ++i;
       
   560       return i; 
       
   561     }
       
   562 
       
   563     //    KEEP_MAPS(Parent, SubGraphWrapper);
       
   564   };
       
   565 
       
   566 
       
   567   /*! \brief A wrapper for hiding nodes from a graph.
       
   568 
       
   569   \warning Graph wrappers are in even more experimental state than the other
       
   570   parts of the lib. Use them at you own risk.
       
   571   
       
   572   A wrapper for hiding nodes from a graph.
       
   573   This wrapper specializes SubGraphWrapper in the way that only the node-set 
       
   574   can be filtered. Note that this does not mean of considering induced 
       
   575   subgraph, the edge-iterators consider the original edge-set.
       
   576   \author Marton Makai
       
   577   */
       
   578   template<typename Graph, typename NodeFilterMap>
       
   579   class NodeSubGraphWrapper : 
       
   580     public SubGraphWrapper<Graph, NodeFilterMap, 
       
   581 			   ConstMap<typename Graph::Edge,bool> > {
       
   582   public:
       
   583     typedef SubGraphWrapper<Graph, NodeFilterMap, 
       
   584 			    ConstMap<typename Graph::Edge,bool> > Parent;
       
   585   protected:
       
   586     ConstMap<typename Graph::Edge, bool> const_true_map;
       
   587   public:
       
   588     NodeSubGraphWrapper(Graph& _graph, NodeFilterMap& _node_filter_map) : 
       
   589       Parent(), const_true_map(true) { 
       
   590       Parent::setGraph(_graph);
       
   591       Parent::setNodeFilterMap(_node_filter_map);
       
   592       Parent::setEdgeFilterMap(const_true_map);
       
   593     }
       
   594   };
       
   595 
       
   596 
       
   597   /*! \brief A wrapper for hiding edges from a graph.
       
   598 
       
   599   \warning Graph wrappers are in even more experimental state than the other
       
   600   parts of the lib. Use them at you own risk.
       
   601   
       
   602   A wrapper for hiding edges from a graph.
       
   603   This wrapper specializes SubGraphWrapper in the way that only the edge-set 
       
   604   can be filtered. The usefulness of this wrapper is demonstrated in the 
       
   605   problem of searching a maximum number of edge-disjoint shortest paths 
       
   606   between 
       
   607   two nodes \c s and \c t. Shortest here means being shortest w.r.t. 
       
   608   non-negative edge-lengths. Note that 
       
   609   the comprehension of the presented solution 
       
   610   need's some knowledge from elementary combinatorial optimization. 
       
   611 
       
   612   If a single shortest path is to be 
   373   searched between two nodes \c s and \c t, then this can be done easily by 
   613   searched between two nodes \c s and \c t, then this can be done easily by 
   374   applying the Dijkstra algorithm class. What happens, if a maximum number of 
   614   applying the Dijkstra algorithm class. What happens, if a maximum number of 
   375   edge-disjoint shortest paths is to be computed. It can be proved that an 
   615   edge-disjoint shortest paths is to be computed. It can be proved that an 
   376   edge can be in a shortest path if and only if it is tight with respect to 
   616   edge can be in a shortest path if and only if it is tight with respect to 
   377   the potential function computed by Dijkstra. Moreover, any path containing 
   617   the potential function computed by Dijkstra. Moreover, any path containing 
   378   only such edges is a shortest one. Thus we have to compute a maximum number 
   618   only such edges is a shortest one. Thus we have to compute a maximum number 
   379   of edge-disjoint path between \c s and \c t in the graph which has edge-set 
   619   of edge-disjoint paths between \c s and \c t in the graph which has edge-set 
   380   all the tight edges. The computation will be demonstrated on the following 
   620   all the tight edges. The computation will be demonstrated on the following 
   381   graph, which is read from a dimacs file.
   621   graph, which is read from a dimacs file.
   382   
   622   
   383   \dot
   623   \dot
   384   digraph lemon_dot_example {
   624   digraph lemon_dot_example {
   475    7, 3--1->5
   715    7, 3--1->5
   476    4, 2--2->4
   716    4, 2--2->4
   477    2, 0--1->3
   717    2, 0--1->3
   478    1, 0--2->2
   718    1, 0--2->2
   479   \endcode
   719   \endcode
   480   \author Marton Makai
   720 
   481   */
       
   482   template<typename Graph, typename NodeFilterMap, 
       
   483 	   typename EdgeFilterMap>
       
   484   class SubGraphWrapper : public GraphWrapper<Graph> {
       
   485   public:
       
   486     typedef GraphWrapper<Graph> Parent;
       
   487   protected:
       
   488     NodeFilterMap* node_filter_map;
       
   489     EdgeFilterMap* edge_filter_map;
       
   490 
       
   491     SubGraphWrapper() : GraphWrapper<Graph>(), 
       
   492 			node_filter_map(0), edge_filter_map(0) { }
       
   493     void setNodeFilterMap(NodeFilterMap& _node_filter_map) {
       
   494       node_filter_map=&_node_filter_map;
       
   495     }
       
   496     void setEdgeFilterMap(EdgeFilterMap& _edge_filter_map) {
       
   497       edge_filter_map=&_edge_filter_map;
       
   498     }
       
   499     
       
   500   public:
       
   501     SubGraphWrapper(Graph& _graph, NodeFilterMap& _node_filter_map, 
       
   502 		    EdgeFilterMap& _edge_filter_map) : 
       
   503       GraphWrapper<Graph>(_graph), node_filter_map(&_node_filter_map), 
       
   504       edge_filter_map(&_edge_filter_map) { }  
       
   505 
       
   506     typedef typename GraphWrapper<Graph>::Node Node;
       
   507     class NodeIt : public Node { 
       
   508       const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>* gw;
       
   509       friend class SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>;
       
   510     public:
       
   511       NodeIt() { }
       
   512       NodeIt(Invalid i) : Node(i) { }
       
   513       NodeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw) : 
       
   514 	Node(typename Graph::NodeIt(*(_gw.graph))), gw(&_gw) { 
       
   515 	while (*static_cast<Node*>(this)!=INVALID && 
       
   516 	       !(*(gw->node_filter_map))[*this]) 
       
   517 	  *(static_cast<Node*>(this))=
       
   518 	    ++(typename Graph::NodeIt(*(gw->graph), *this));
       
   519       }
       
   520       NodeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw, 
       
   521 	     const Node& n) : 
       
   522 	Node(n), gw(&_gw) { }
       
   523       NodeIt& operator++() { 
       
   524 	*(static_cast<Node*>(this))=
       
   525 	  ++(typename Graph::NodeIt(*(gw->graph), *this));
       
   526 	while (*static_cast<Node*>(this)!=INVALID && 
       
   527 	       !(*(gw->node_filter_map))[*this]) 
       
   528 	  *(static_cast<Node*>(this))=
       
   529 	    ++(typename Graph::NodeIt(*(gw->graph), *this));
       
   530 	return *this; 
       
   531       }
       
   532     };
       
   533     typedef typename GraphWrapper<Graph>::Edge Edge;
       
   534     class OutEdgeIt : public Edge { 
       
   535       const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>* gw;
       
   536       friend class SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>;
       
   537     public:
       
   538       OutEdgeIt() { }
       
   539       OutEdgeIt(Invalid i) : Edge(i) { }
       
   540       OutEdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw, const Node& n) : 
       
   541 	Edge(typename Graph::OutEdgeIt(*(_gw.graph), n)), gw(&_gw) { 
       
   542 	while (*static_cast<Edge*>(this)!=INVALID && 
       
   543 	       !(*(gw->edge_filter_map))[*this]) 
       
   544 	  *(static_cast<Edge*>(this))=
       
   545 	    ++(typename Graph::OutEdgeIt(*(gw->graph), *this));
       
   546       }
       
   547       OutEdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw, 
       
   548 	     const Edge& e) : 
       
   549 	Edge(e), gw(&_gw) { }
       
   550       OutEdgeIt& operator++() { 
       
   551 	*(static_cast<Edge*>(this))=
       
   552 	  ++(typename Graph::OutEdgeIt(*(gw->graph), *this));
       
   553 	while (*static_cast<Edge*>(this)!=INVALID && 
       
   554 	       !(*(gw->edge_filter_map))[*this]) 
       
   555 	  *(static_cast<Edge*>(this))=
       
   556 	    ++(typename Graph::OutEdgeIt(*(gw->graph), *this));
       
   557 	return *this; 
       
   558       }
       
   559     };
       
   560     class InEdgeIt : public Edge { 
       
   561       const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>* gw;
       
   562       friend class SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>;
       
   563     public:
       
   564       InEdgeIt() { }
       
   565       //      InEdgeIt(const InEdgeIt& e) : Edge(e), gw(e.gw) { }
       
   566       InEdgeIt(Invalid i) : Edge(i) { }
       
   567       InEdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw, const Node& n) : 
       
   568 	Edge(typename Graph::InEdgeIt(*(_gw.graph), n)), gw(&_gw) { 
       
   569 	while (*static_cast<Edge*>(this)!=INVALID && 
       
   570 	       !(*(gw->edge_filter_map))[*this]) 
       
   571 	  *(static_cast<Edge*>(this))=
       
   572 	    ++(typename Graph::InEdgeIt(*(gw->graph), *this));
       
   573       }
       
   574       InEdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw, 
       
   575 	     const Edge& e) : 
       
   576 	Edge(e), gw(&_gw) { }
       
   577       InEdgeIt& operator++() { 
       
   578 	*(static_cast<Edge*>(this))=
       
   579 	  ++(typename Graph::InEdgeIt(*(gw->graph), *this));
       
   580 	while (*static_cast<Edge*>(this)!=INVALID && 
       
   581 	       !(*(gw->edge_filter_map))[*this]) 
       
   582 	  *(static_cast<Edge*>(this))=
       
   583 	    ++(typename Graph::InEdgeIt(*(gw->graph), *this));
       
   584 	return *this; 
       
   585       }
       
   586     };
       
   587     class EdgeIt : public Edge { 
       
   588       const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>* gw;
       
   589       friend class SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>;
       
   590     public:
       
   591       EdgeIt() { }
       
   592       EdgeIt(Invalid i) : Edge(i) { }
       
   593       EdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw) : 
       
   594 	Edge(typename Graph::EdgeIt(*(_gw.graph))), gw(&_gw) { 
       
   595 	while (*static_cast<Edge*>(this)!=INVALID && 
       
   596 	       !(*(gw->edge_filter_map))[*this]) 
       
   597 	  *(static_cast<Edge*>(this))=
       
   598 	    ++(typename Graph::EdgeIt(*(gw->graph), *this));
       
   599       }
       
   600       EdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _gw, 
       
   601 	     const Edge& e) : 
       
   602 	Edge(e), gw(&_gw) { }
       
   603       EdgeIt& operator++() { 
       
   604 	*(static_cast<Edge*>(this))=
       
   605 	  ++(typename Graph::EdgeIt(*(gw->graph), *this));
       
   606 	while (*static_cast<Edge*>(this)!=INVALID && 
       
   607 	       !(*(gw->edge_filter_map))[*this]) 
       
   608 	  *(static_cast<Edge*>(this))=
       
   609 	    ++(typename Graph::EdgeIt(*(gw->graph), *this));
       
   610 	return *this; 
       
   611       }
       
   612     };
       
   613 
       
   614     NodeIt& first(NodeIt& i) const { 
       
   615       i=NodeIt(*this); return i;
       
   616     }
       
   617     OutEdgeIt& first(OutEdgeIt& i, const Node& p) const { 
       
   618       i=OutEdgeIt(*this, p); return i;
       
   619     }
       
   620     InEdgeIt& first(InEdgeIt& i, const Node& p) const { 
       
   621       i=InEdgeIt(*this, p); return i;
       
   622     }
       
   623     EdgeIt& first(EdgeIt& i) const { 
       
   624       i=EdgeIt(*this); return i;
       
   625     }
       
   626     
       
   627     /// This function hides \c n in the graph, i.e. the iteration 
       
   628     /// jumps over it. This is done by simply setting the value of \c n  
       
   629     /// to be false in the corresponding node-map.
       
   630     void hide(const Node& n) const { node_filter_map->set(n, false); }
       
   631 
       
   632     /// This function hides \c e in the graph, i.e. the iteration 
       
   633     /// jumps over it. This is done by simply setting the value of \c e  
       
   634     /// to be false in the corresponding edge-map.
       
   635     void hide(const Edge& e) const { edge_filter_map->set(e, false); }
       
   636 
       
   637     /// The value of \c n is set to be true in the node-map which stores 
       
   638     /// hide information. If \c n was hidden previuosly, then it is shown 
       
   639     /// again
       
   640      void unHide(const Node& n) const { node_filter_map->set(n, true); }
       
   641 
       
   642     /// The value of \c e is set to be true in the edge-map which stores 
       
   643     /// hide information. If \c e was hidden previuosly, then it is shown 
       
   644     /// again
       
   645     void unHide(const Edge& e) const { edge_filter_map->set(e, true); }
       
   646 
       
   647     /// Returns true if \c n is hidden.
       
   648     bool hidden(const Node& n) const { return !(*node_filter_map)[n]; }
       
   649 
       
   650     /// Returns true if \c n is hidden.
       
   651     bool hidden(const Edge& e) const { return !(*edge_filter_map)[e]; }
       
   652 
       
   653     /// \warning This is a linear time operation and works only if 
       
   654     /// \c Graph::NodeIt is defined.
       
   655     int nodeNum() const { 
       
   656       int i=0;
       
   657       for (NodeIt n(*this); n!=INVALID; ++n) ++i;
       
   658       return i; 
       
   659     }
       
   660 
       
   661     /// \warning This is a linear time operation and works only if 
       
   662     /// \c Graph::EdgeIt is defined.
       
   663     int edgeNum() const { 
       
   664       int i=0;
       
   665       for (EdgeIt e(*this); e!=INVALID; ++e) ++i;
       
   666       return i; 
       
   667     }
       
   668 
       
   669     //    KEEP_MAPS(Parent, SubGraphWrapper);
       
   670   };
       
   671 
       
   672 
       
   673   /*! \brief A wrapper for hiding edges from a graph.
       
   674 
       
   675   \warning Graph wrappers are in even more experimental state than the other
       
   676   parts of the lib. Use them at you own risk.
       
   677   
       
   678   A wrapper for hiding edges from a graph.
       
   679   This wrapper specializes SubGraphWrapper in the way that only the edge-set 
       
   680   can be filtered.
       
   681   \author Marton Makai
   721   \author Marton Makai
   682   */
   722   */
   683   template<typename Graph, typename EdgeFilterMap>
   723   template<typename Graph, typename EdgeFilterMap>
   684   class EdgeSubGraphWrapper : 
   724   class EdgeSubGraphWrapper : 
   685     public SubGraphWrapper<Graph, ConstMap<typename Graph::Node,bool>, 
   725     public SubGraphWrapper<Graph, ConstMap<typename Graph::Node,bool>,