src/work/marci/graph_wrapper.h
author marci
Fri, 30 Apr 2004 19:02:40 +0000
changeset 502 1b41ebb5fee5
parent 497 500456d50d21
child 524 bd8109f8e2fa
permissions -rw-r--r--
static const bool BipartiteGraphWrapper<Graph>::S_CLASS, T_CLASS
     1 // -*- c++ -*-
     2 #ifndef HUGO_GRAPH_WRAPPER_H
     3 #define HUGO_GRAPH_WRAPPER_H
     4 
     5 ///\ingroup gwrappers
     6 ///\file
     7 ///\brief Several graph wrappers.
     8 ///
     9 ///This file contains several useful graph wrapper functions.
    10 ///
    11 ///\author Marton Makai
    12 
    13 #include <invalid.h>
    14 //#include <iter_map.h>
    15 
    16 namespace hugo {
    17 
    18   // Graph wrappers
    19 
    20   /// \addtogroup gwrappers
    21   /// A main parts of HUGOlib are the different graph structures, 
    22   /// generic graph algorithms, graph concepts which couple these, and 
    23   /// graph wrappers. While the previous ones are more or less clear, the 
    24   /// latter notion needs further explanation.
    25   /// Graph wrappers are graph classes which serve for considering graph 
    26   /// structures in different ways. A short example makes the notion much 
    27   /// clearer. 
    28   /// Suppose that we have an instance \c g of a directed graph
    29   /// type say \c ListGraph and an algorithm 
    30   /// \code template<typename Graph> int algorithm(const Graph&); \endcode 
    31   /// is needed to run on the reversely oriented graph. 
    32   /// It may be expensive (in time or in memory usage) to copy 
    33   /// \c g with the reverse orientation. 
    34   /// Thus, a wrapper class
    35   /// \code template<typename Graph> class RevGraphWrapper; \endcode is used. 
    36   /// The code looks as follows
    37   /// \code
    38   /// ListGraph g;
    39   /// RevGraphWrapper<ListGraph> rgw(g);
    40   /// int result=algorithm(rgw);
    41   /// \endcode
    42   /// After running the algorithm, the original graph \c g 
    43   /// remains untouched. Thus the graph wrapper used above is to consider the 
    44   /// original graph with reverse orientation. 
    45   /// This techniques gives rise to an elegant code, and 
    46   /// based on stable graph wrappers, complex algorithms can be 
    47   /// implemented easily. 
    48   /// In flow, circulation and bipartite matching problems, the residual 
    49   /// graph is of particular importance. Combining a wrapper implementing 
    50   /// this, shortest path algorithms and minimum mean cycle algorithms, 
    51   /// a range of weighted and cardinality optimization algorithms can be 
    52   /// obtained. For lack of space, for other examples, 
    53   /// the interested user is referred to the detailed documentation of graph 
    54   /// wrappers. 
    55   /// The behavior of graph wrappers can be very different. Some of them keep 
    56   /// capabilities of the original graph while in other cases this would be 
    57   /// meaningless. This means that the concepts that they are a model of depend 
    58   /// on the graph wrapper, and the wrapped graph(s). 
    59   /// If an edge of \c rgw is deleted, this is carried out by 
    60   /// deleting the corresponding edge of \c g. But for a residual 
    61   /// graph, this operation has no sense. 
    62   /// Let we stand one more example here to simplify your work. 
    63   /// wrapper class
    64   /// \code template<typename Graph> class RevGraphWrapper; \endcode 
    65   /// has constructor 
    66   /// <tt> RevGraphWrapper(Graph& _g)</tt>. 
    67   /// This means that in a situation, 
    68   /// when a <tt> const ListGraph& </tt> reference to a graph is given, 
    69   /// then it have to be instantiated with <tt>Graph=const ListGraph</tt>.
    70   /// \code
    71   /// int algorithm1(const ListGraph& g) {
    72   ///   RevGraphWrapper<const ListGraph> rgw(g);
    73   ///   return algorithm2(rgw);
    74   /// }
    75   /// \endcode
    76 
    77   /// \addtogroup gwrappers
    78   /// @{
    79 
    80   ///Base type for the Graph Wrappers
    81 
    82   ///This is the base type for the Graph Wrappers.
    83   ///\todo Some more docs... 
    84   ///
    85   ///\author Marton Makai
    86  
    87   template<typename Graph>
    88   class GraphWrapper {
    89   protected:
    90     Graph* graph;
    91     GraphWrapper() : graph(0) { }
    92     void setGraph(Graph& _graph) { graph=&_graph; }
    93 
    94   public:
    95     typedef Graph BaseGraph;
    96     typedef Graph ParentGraph;
    97 
    98     GraphWrapper(Graph& _graph) : graph(&_graph) { }
    99 //     Graph& getGraph() const { return *graph; }
   100  
   101 //    typedef typename Graph::Node Node;
   102     class Node : public Graph::Node {
   103       friend class GraphWrapper<Graph>;
   104     public:
   105       Node() { }
   106       Node(const typename Graph::Node& _n) : Graph::Node(_n) { }
   107       Node(const Invalid& i) : Graph::Node(i) { }
   108     };
   109     class NodeIt { 
   110       friend class GraphWrapper<Graph>;
   111       typename Graph::NodeIt n;
   112      public:
   113       NodeIt() { }
   114       NodeIt(const typename Graph::NodeIt& _n) : n(_n) { }
   115       NodeIt(const Invalid& i) : n(i) { }
   116       NodeIt(const GraphWrapper<Graph>& _G) : n(*(_G.graph)) { }
   117       operator Node() const { return Node(typename Graph::Node(n)); }
   118     };
   119 //    typedef typename Graph::Edge Edge;
   120     class Edge : public Graph::Edge {
   121       friend class GraphWrapper<Graph>;
   122     public:
   123       Edge() { }
   124       Edge(const typename Graph::Edge& _e) : Graph::Edge(_e) { }
   125       Edge(const Invalid& i) : Graph::Edge(i) { }
   126     };
   127     class OutEdgeIt { 
   128       friend class GraphWrapper<Graph>;
   129       typename Graph::OutEdgeIt e;
   130     public:
   131       OutEdgeIt() { }
   132       OutEdgeIt(const typename Graph::OutEdgeIt& _e) : e(_e) { }
   133       OutEdgeIt(const Invalid& i) : e(i) { }
   134       OutEdgeIt(const GraphWrapper<Graph>& _G, const Node& _n) : 
   135 	e(*(_G.graph), typename Graph::Node(_n)) { }
   136       operator Edge() const { return Edge(typename Graph::Edge(e)); }
   137     };
   138     class InEdgeIt { 
   139       friend class GraphWrapper<Graph>;
   140       typename Graph::InEdgeIt e;
   141     public:
   142       InEdgeIt() { }
   143       InEdgeIt(const typename Graph::InEdgeIt& _e) : e(_e) { }
   144       InEdgeIt(const Invalid& i) : e(i) { }
   145       InEdgeIt(const GraphWrapper<Graph>& _G, const Node& _n) : 
   146 	e(*(_G.graph), typename Graph::Node(_n)) { }
   147       operator Edge() const { return Edge(typename Graph::Edge(e)); }
   148     };
   149     //typedef typename Graph::SymEdgeIt SymEdgeIt;
   150     class EdgeIt { 
   151       friend class GraphWrapper<Graph>;
   152       typename Graph::EdgeIt e;
   153     public:
   154       EdgeIt() { }
   155       EdgeIt(const typename Graph::EdgeIt& _e) : e(_e) { }
   156       EdgeIt(const Invalid& i) : e(i) { }
   157       EdgeIt(const GraphWrapper<Graph>& _G) : e(*(_G.graph)) { }
   158       operator Edge() const { return Edge(typename Graph::Edge(e)); }
   159     };
   160    
   161     NodeIt& first(NodeIt& i) const { 
   162       i=NodeIt(*this); return i;
   163     }
   164     OutEdgeIt& first(OutEdgeIt& i, const Node& p) const { 
   165       i=OutEdgeIt(*this, p); return i;
   166     }
   167     InEdgeIt& first(InEdgeIt& i, const Node& p) const { 
   168       i=InEdgeIt(*this, p); return i;
   169     }
   170     EdgeIt& first(EdgeIt& i) const { 
   171       i=EdgeIt(*this); return i;
   172     }
   173 
   174     NodeIt& next(NodeIt& i) const { graph->next(i.n); return i; }
   175     OutEdgeIt& next(OutEdgeIt& i) const { graph->next(i.e); return i; }
   176     InEdgeIt& next(InEdgeIt& i) const { graph->next(i.e); return i; }
   177     EdgeIt& next(EdgeIt& i) const { graph->next(i.e); return i; }    
   178 
   179     Node tail(const Edge& e) const { 
   180       return Node(graph->tail(static_cast<typename Graph::Edge>(e))); }
   181     Node head(const Edge& e) const { 
   182       return Node(graph->head(static_cast<typename Graph::Edge>(e))); }
   183 
   184     bool valid(const Node& n) const { 
   185       return graph->valid(static_cast<typename Graph::Node>(n)); }
   186     bool valid(const Edge& e) const { 
   187       return graph->valid(static_cast<typename Graph::Edge>(e)); }
   188 
   189     int nodeNum() const { return graph->nodeNum(); }
   190     int edgeNum() const { return graph->edgeNum(); }
   191   
   192     Node aNode(const OutEdgeIt& e) const { return Node(graph->aNode(e.e)); }
   193     Node aNode(const InEdgeIt& e) const { return Node(graph->aNode(e.e)); }
   194     Node bNode(const OutEdgeIt& e) const { return Node(graph->bNode(e.e)); }
   195     Node bNode(const InEdgeIt& e) const { return Node(graph->bNode(e.e)); }
   196   
   197     Node addNode() const { return Node(graph->addNode()); }
   198     Edge addEdge(const Node& tail, const Node& head) const { 
   199       return Edge(graph->addEdge(tail, head)); }
   200 
   201     void erase(const Node& i) const { graph->erase(i); }
   202     void erase(const Edge& i) const { graph->erase(i); }
   203   
   204     void clear() const { graph->clear(); }
   205     
   206     template<typename T> class NodeMap : public Graph::template NodeMap<T> { 
   207       typedef typename Graph::template NodeMap<T> Parent;
   208     public:
   209       NodeMap(const GraphWrapper<Graph>& _G) :  Parent(*(_G.graph)) { }
   210       NodeMap(const GraphWrapper<Graph>& _G, T a) : Parent(*(_G.graph), a) { }
   211     };
   212 
   213     template<typename T> class EdgeMap : public Graph::template EdgeMap<T> { 
   214       typedef typename Graph::template EdgeMap<T> Parent;
   215     public:
   216       EdgeMap(const GraphWrapper<Graph>& _G) : Parent(*(_G.graph)) { }
   217       EdgeMap(const GraphWrapper<Graph>& _G, T a) : Parent(*(_G.graph), a) { }
   218     };
   219   };
   220 
   221   /// A graph wrapper which reverses the orientation of the edges.
   222 
   223   /// A graph wrapper which reverses the orientation of the edges.
   224   ///
   225   ///\author Marton Makai
   226   template<typename Graph>
   227   class RevGraphWrapper : public GraphWrapper<Graph> {
   228   protected:
   229     RevGraphWrapper() : GraphWrapper<Graph>(0) { }
   230   public:
   231     RevGraphWrapper(Graph& _graph) : GraphWrapper<Graph>(_graph) { }  
   232 
   233     typedef typename GraphWrapper<Graph>::Node Node;
   234     typedef typename GraphWrapper<Graph>::Edge Edge;
   235     //If Graph::OutEdgeIt is not defined
   236     //and we do not want to use RevGraphWrapper::InEdgeIt,
   237     //the typdef techinque does not work.
   238     //Unfortunately all the typedefs are instantiated in templates.
   239     //typedef typename GraphWrapper<Graph>::OutEdgeIt InEdgeIt;
   240     //typedef typename GraphWrapper<Graph>::InEdgeIt OutEdgeIt;
   241 
   242     class OutEdgeIt { 
   243       friend class GraphWrapper<Graph>;
   244       friend class RevGraphWrapper<Graph>;
   245       typename Graph::InEdgeIt e;
   246     public:
   247       OutEdgeIt() { }
   248       OutEdgeIt(const typename Graph::InEdgeIt& _e) : e(_e) { }
   249       OutEdgeIt(const Invalid& i) : e(i) { }
   250       OutEdgeIt(const RevGraphWrapper<Graph>& _G, const Node& _n) : 
   251 	e(*(_G.graph), typename Graph::Node(_n)) { }
   252       operator Edge() const { return Edge(typename Graph::Edge(e)); }
   253     };
   254     class InEdgeIt { 
   255       friend class GraphWrapper<Graph>;
   256       friend class RevGraphWrapper<Graph>;
   257       typename Graph::OutEdgeIt e;
   258     public:
   259       InEdgeIt() { }
   260       InEdgeIt(const typename Graph::OutEdgeIt& _e) : e(_e) { }
   261       InEdgeIt(const Invalid& i) : e(i) { }
   262       InEdgeIt(const RevGraphWrapper<Graph>& _G, const Node& _n) : 
   263 	e(*(_G.graph), typename Graph::Node(_n)) { }
   264       operator Edge() const { return Edge(typename Graph::Edge(e)); }
   265     };
   266 
   267     using GraphWrapper<Graph>::first;
   268     OutEdgeIt& first(OutEdgeIt& i, const Node& p) const { 
   269       i=OutEdgeIt(*this, p); return i;
   270     }
   271     InEdgeIt& first(InEdgeIt& i, const Node& p) const { 
   272       i=InEdgeIt(*this, p); return i;
   273     }
   274 
   275     using GraphWrapper<Graph>::next;
   276     OutEdgeIt& next(OutEdgeIt& i) const { this->graph->next(i.e); return i; }
   277     InEdgeIt& next(InEdgeIt& i) const { this->graph->next(i.e); return i; }
   278 
   279     Node aNode(const OutEdgeIt& e) const { 
   280       return Node(this->graph->aNode(e.e)); }
   281     Node aNode(const InEdgeIt& e) const { 
   282       return Node(this->graph->aNode(e.e)); }
   283     Node bNode(const OutEdgeIt& e) const { 
   284       return Node(this->graph->bNode(e.e)); }
   285     Node bNode(const InEdgeIt& e) const { 
   286       return Node(this->graph->bNode(e.e)); }
   287 
   288     Node tail(const Edge& e) const { 
   289       return GraphWrapper<Graph>::head(e); }
   290     Node head(const Edge& e) const { 
   291       return GraphWrapper<Graph>::tail(e); }
   292 
   293   };
   294 
   295   /// Wrapper for hiding nodes and edges from a graph.
   296   
   297   /// This wrapper shows a graph with filtered node-set and 
   298   /// edge-set. The quick brown fox iterator jumps over 
   299   /// the lazy dog nodes or edges if the values for them are false 
   300   /// in the bool maps. 
   301   ///
   302   ///\author Marton Makai
   303   template<typename Graph, typename NodeFilterMap, 
   304 	   typename EdgeFilterMap>
   305   class SubGraphWrapper : public GraphWrapper<Graph> {
   306   protected:
   307     NodeFilterMap* node_filter_map;
   308     EdgeFilterMap* edge_filter_map;
   309 
   310     SubGraphWrapper() : GraphWrapper<Graph>(0), 
   311 			node_filter_map(0), edge_filter_map(0) { }
   312     void setNodeFilterMap(NodeFilterMap& _node_filter_map) {
   313       node_filter_map=&_node_filte_map;
   314     }
   315     void setEdgeFilterMap(EdgeFilterMap& _edge_filter_map) {
   316       edge_filter_map=&_edge_filte_map;
   317     }
   318     
   319   public:
   320 
   321     SubGraphWrapper(Graph& _graph, NodeFilterMap& _node_filter_map, 
   322 		    EdgeFilterMap& _edge_filter_map) : 
   323       GraphWrapper<Graph>(_graph), node_filter_map(&_node_filter_map), 
   324       edge_filter_map(&_edge_filter_map) { }  
   325 
   326     typedef typename GraphWrapper<Graph>::Node Node;
   327     class NodeIt { 
   328       friend class GraphWrapper<Graph>;
   329       friend class SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>;
   330       typename Graph::NodeIt n;
   331      public:
   332       NodeIt() { }
   333       NodeIt(const typename Graph::NodeIt& _n) : n(_n) { }
   334       NodeIt(const Invalid& i) : n(i) { }
   335       NodeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _G) : 
   336 	n(*(_G.graph)) { 
   337 	while (_G.graph->valid(n) && !(*(_G.node_filter_map))[n]) 
   338 	  _G.graph->next(n);
   339       }
   340       operator Node() const { return Node(typename Graph::Node(n)); }
   341     };
   342     typedef typename GraphWrapper<Graph>::Edge Edge;
   343     class OutEdgeIt { 
   344       friend class GraphWrapper<Graph>;
   345       friend class SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>;
   346       typename Graph::OutEdgeIt e;
   347     public:
   348       OutEdgeIt() { }
   349       OutEdgeIt(const typename Graph::OutEdgeIt& _e) : e(_e) { }
   350       OutEdgeIt(const Invalid& i) : e(i) { }
   351       OutEdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _G, 
   352 		const Node& _n) : 
   353 	e(*(_G.graph), typename Graph::Node(_n)) { 
   354       	while (_G.graph->valid(e) && !(*(_G.edge_filter_map))[e]) 
   355 	  _G.graph->next(e);
   356       }
   357       operator Edge() const { return Edge(typename Graph::Edge(e)); }
   358     };
   359     class InEdgeIt { 
   360       friend class GraphWrapper<Graph>;
   361       friend class SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>;
   362       typename Graph::InEdgeIt e;
   363     public:
   364       InEdgeIt() { }
   365       InEdgeIt(const typename Graph::InEdgeIt& _e) : e(_e) { }
   366       InEdgeIt(const Invalid& i) : e(i) { }
   367       InEdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _G, 
   368 	       const Node& _n) : 
   369 	e(*(_G.graph), typename Graph::Node(_n)) { 
   370       	while (_G.graph->valid(e) && !(*(_G.edge_filter_map))[e]) 
   371 	  _G.graph->next(e);
   372       }
   373       operator Edge() const { return Edge(typename Graph::Edge(e)); }
   374     };
   375     //typedef typename Graph::SymEdgeIt SymEdgeIt;
   376     class EdgeIt { 
   377       friend class GraphWrapper<Graph>;
   378       friend class SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>;
   379       typename Graph::EdgeIt e;
   380     public:
   381       EdgeIt() { }
   382       EdgeIt(const typename Graph::EdgeIt& _e) : e(_e) { }
   383       EdgeIt(const Invalid& i) : e(i) { }
   384       EdgeIt(const SubGraphWrapper<Graph, NodeFilterMap, EdgeFilterMap>& _G) : 
   385 	e(*(_G.graph)) { 
   386       	while (_G.graph->valid(e) && !(*(_G.edge_filter_map))[e]) 
   387 	  _G.graph->next(e);
   388       }
   389       operator Edge() const { return Edge(typename Graph::Edge(e)); }
   390     };
   391 
   392     NodeIt& first(NodeIt& i) const { 
   393       i=NodeIt(*this); return i;
   394     }
   395     OutEdgeIt& first(OutEdgeIt& i, const Node& p) const { 
   396       i=OutEdgeIt(*this, p); return i;
   397     }
   398     InEdgeIt& first(InEdgeIt& i, const Node& p) const { 
   399       i=InEdgeIt(*this, p); return i;
   400     }
   401     EdgeIt& first(EdgeIt& i) const { 
   402       i=EdgeIt(*this); return i;
   403     }
   404     
   405     NodeIt& next(NodeIt& i) const {
   406       this->graph->next(i.n); 
   407       while (this->graph->valid(i) && !(*node_filter_map)[i.n]) { 
   408 	this->graph->next(i.n); }
   409       return i;
   410     }
   411     OutEdgeIt& next(OutEdgeIt& i) const {
   412       this->graph->next(i.e); 
   413       while (this->graph->valid(i) && !(*edge_filter_map)[i.e]) { 
   414 	this->graph->next(i.e); }
   415       return i;
   416     }
   417     InEdgeIt& next(InEdgeIt& i) const {
   418       this->graph->next(i.e); 
   419       while (this->graph->valid(i) && !(*edge_filter_map)[i.e]) { 
   420 	this->graph->next(i.e); }
   421       return i;
   422     }
   423     EdgeIt& next(EdgeIt& i) const {
   424       this->graph->next(i.e); 
   425       while (this->graph->valid(i) && !(*edge_filter_map)[i.e]) { 
   426 	this->graph->next(i.e); }
   427       return i;
   428     }
   429 
   430     Node aNode(const OutEdgeIt& e) const { 
   431       return Node(this->graph->aNode(e.e)); }
   432     Node aNode(const InEdgeIt& e) const { 
   433       return Node(this->graph->aNode(e.e)); }
   434     Node bNode(const OutEdgeIt& e) const { 
   435       return Node(this->graph->bNode(e.e)); }
   436     Node bNode(const InEdgeIt& e) const { 
   437       return Node(this->graph->bNode(e.e)); }
   438 
   439     ///\todo
   440     ///Some doki, please.
   441     void hide(const Node& n) const { node_filter_map->set(n, false); }
   442     ///\todo
   443     ///Some doki, please.
   444     void hide(const Edge& e) const { edge_filter_map->set(e, false); }
   445 
   446     ///\todo
   447     ///Some doki, please.
   448     void unHide(const Node& n) const { node_filter_map->set(n, true); }
   449     ///\todo
   450     ///Some doki, please.
   451     void unHide(const Edge& e) const { edge_filter_map->set(e, true); }
   452 
   453     ///\todo
   454     ///Some doki, please.
   455     bool hidden(const Node& n) const { return (*node_filter_map)[n]; }
   456     ///\todo
   457     ///Some doki, please.
   458     bool hidden(const Edge& e) const { return (*edge_filter_map)[e]; }
   459   };
   460 
   461   /// A wrapper for forgetting the orientation of a graph.
   462 
   463   /// A wrapper for getting an undirected graph by forgetting
   464   /// the orientation of a directed one.
   465   template<typename Graph>
   466   class UndirGraphWrapper : public GraphWrapper<Graph> {
   467   protected:
   468     UndirGraphWrapper() : GraphWrapper<Graph>(0) { }
   469     
   470   public:
   471     typedef typename GraphWrapper<Graph>::Node Node;
   472     typedef typename GraphWrapper<Graph>::NodeIt NodeIt;
   473     typedef typename GraphWrapper<Graph>::Edge Edge;
   474     typedef typename GraphWrapper<Graph>::EdgeIt EdgeIt;
   475 
   476     UndirGraphWrapper(Graph& _graph) : GraphWrapper<Graph>(_graph) { }  
   477 
   478     class OutEdgeIt {
   479       friend class UndirGraphWrapper<Graph>;
   480       bool out_or_in; //true iff out
   481       typename Graph::OutEdgeIt out;
   482       typename Graph::InEdgeIt in;
   483     public:
   484       OutEdgeIt() { }
   485       OutEdgeIt(const Invalid& i) : Edge(i) { }
   486       OutEdgeIt(const UndirGraphWrapper<Graph>& _G, const Node& _n) {
   487 	out_or_in=true; _G.graph->first(out, _n);
   488 	if (!(_G.graph->valid(out))) { out_or_in=false; _G.graph->first(in, _n);	}
   489       } 
   490       operator Edge() const { 
   491 	if (out_or_in) return Edge(out); else return Edge(in); 
   492       }
   493     };
   494 
   495 //FIXME InEdgeIt
   496     typedef OutEdgeIt InEdgeIt; 
   497 
   498     using GraphWrapper<Graph>::first;
   499 //     NodeIt& first(NodeIt& i) const { 
   500 //       i=NodeIt(*this); return i;
   501 //     }
   502     OutEdgeIt& first(OutEdgeIt& i, const Node& p) const { 
   503       i=OutEdgeIt(*this, p); return i;
   504     }
   505 //FIXME
   506 //     InEdgeIt& first(InEdgeIt& i, const Node& p) const { 
   507 //       i=InEdgeIt(*this, p); return i;
   508 //     }
   509 //     EdgeIt& first(EdgeIt& i) const { 
   510 //       i=EdgeIt(*this); return i;
   511 //     }
   512 
   513     using GraphWrapper<Graph>::next;
   514 //     NodeIt& next(NodeIt& n) const {
   515 //       GraphWrapper<Graph>::next(n);
   516 //       return n;
   517 //     }
   518     OutEdgeIt& next(OutEdgeIt& e) const {
   519       if (e.out_or_in) {
   520 	typename Graph::Node n=this->graph->tail(e.out);
   521 	this->graph->next(e.out);
   522 	if (!this->graph->valid(e.out)) { 
   523 	  e.out_or_in=false; this->graph->first(e.in, n); }
   524       } else {
   525 	this->graph->next(e.in);
   526       }
   527       return e;
   528     }
   529     //FIXME InEdgeIt
   530 //     EdgeIt& next(EdgeIt& e) const {
   531 //       GraphWrapper<Graph>::next(n);
   532 // //      graph->next(e.e);
   533 //       return e;
   534 //     }
   535 
   536     Node aNode(const OutEdgeIt& e) const { 
   537       if (e.out_or_in) return this->graph->tail(e); else 
   538 	return this->graph->head(e); }
   539     Node bNode(const OutEdgeIt& e) const { 
   540       if (e.out_or_in) return this->graph->head(e); else 
   541 	return this->graph->tail(e); }
   542   };
   543   
   544   /// A wrapper for composing the residual graph for directed flow and circulation problems.
   545 
   546   /// A wrapper for composing the residual graph for directed flow and circulation problems.
   547   template<typename Graph, typename Number, 
   548 	   typename CapacityMap, typename FlowMap>
   549   class ResGraphWrapper : public GraphWrapper<Graph> {
   550   protected:
   551     const CapacityMap* capacity;
   552     FlowMap* flow;
   553 
   554     ResGraphWrapper() : GraphWrapper<Graph>(0), 
   555 			capacity(0), flow(0) { }
   556     void setCapacityMap(const CapacityMap& _capacity_map) {
   557       capacity_map=&_capacity_map;
   558     }
   559     void setFlowMap(FlowMap& _flow) {
   560       flow=&_flow;
   561     }
   562 
   563   public:
   564 
   565     ResGraphWrapper(Graph& _graph, const CapacityMap& _capacity, 
   566 		    FlowMap& _flow) : 
   567       GraphWrapper<Graph>(_graph), capacity(&_capacity), flow(&_flow) { }
   568 
   569     class Edge; 
   570     class OutEdgeIt; 
   571     friend class Edge; 
   572     friend class OutEdgeIt; 
   573 
   574     typedef typename GraphWrapper<Graph>::Node Node;
   575     typedef typename GraphWrapper<Graph>::NodeIt NodeIt;
   576     class Edge : public Graph::Edge {
   577       friend class ResGraphWrapper<Graph, Number, CapacityMap, FlowMap>;
   578     protected:
   579       bool forward; //true, iff forward
   580 //      typename Graph::Edge e;
   581     public:
   582       Edge() { }
   583       Edge(const typename Graph::Edge& _e, bool _forward) : 
   584 	Graph::Edge(_e), forward(_forward) { }
   585       Edge(const Invalid& i) : Graph::Edge(i), forward(false) { }
   586 //the unique invalid iterator
   587       friend bool operator==(const Edge& u, const Edge& v) { 
   588 	return (v.forward==u.forward && 
   589 		static_cast<typename Graph::Edge>(u)==
   590 		static_cast<typename Graph::Edge>(v));
   591       } 
   592       friend bool operator!=(const Edge& u, const Edge& v) { 
   593 	return (v.forward!=u.forward || 
   594 		static_cast<typename Graph::Edge>(u)!=
   595 		static_cast<typename Graph::Edge>(v));
   596       } 
   597     };
   598 
   599     class OutEdgeIt {
   600       friend class ResGraphWrapper<Graph, Number, CapacityMap, FlowMap>;
   601     protected:
   602       typename Graph::OutEdgeIt out;
   603       typename Graph::InEdgeIt in;
   604       bool forward;
   605     public:
   606       OutEdgeIt() { }
   607       //FIXME
   608 //      OutEdgeIt(const Edge& e) : Edge(e) { }
   609       OutEdgeIt(const Invalid& i) : out(i), in(i), forward(false) { }
   610 //the unique invalid iterator
   611       OutEdgeIt(const ResGraphWrapper<Graph, Number, CapacityMap, FlowMap>& resG, Node v) { 
   612 	forward=true;
   613 	resG.graph->first(out, v);
   614 	while( resG.graph->valid(out) && !(resG.resCap(*this)>0) ) { resG.graph->next(out); }
   615 	if (!resG.graph->valid(out)) {
   616 	  forward=false;
   617 	  resG.graph->first(in, v);
   618 	  while( resG.graph->valid(in) && !(resG.resCap(*this)>0) ) { resG.graph->next(in); }
   619 	}
   620       }
   621       operator Edge() const { 
   622 //	Edge e;
   623 //	e.forward=this->forward;
   624 //	if (this->forward) e=out; else e=in;
   625 //	return e;
   626 	if (this->forward) 
   627 	  return Edge(out, this->forward); 
   628 	else 
   629 	  return Edge(in, this->forward);
   630       }
   631     };
   632 
   633     class InEdgeIt {
   634       friend class ResGraphWrapper<Graph, Number, CapacityMap, FlowMap>;
   635     protected:
   636       typename Graph::OutEdgeIt out;
   637       typename Graph::InEdgeIt in;
   638       bool forward;
   639     public:
   640       InEdgeIt() { }
   641       //FIXME
   642 //      OutEdgeIt(const Edge& e) : Edge(e) { }
   643       InEdgeIt(const Invalid& i) : out(i), in(i), forward(false) { }
   644 //the unique invalid iterator
   645       InEdgeIt(const ResGraphWrapper<Graph, Number, CapacityMap, FlowMap>& resG, Node v) { 
   646 	forward=true;
   647 	resG.graph->first(in, v);
   648 	while( resG.graph->valid(in) && !(resG.resCap(*this)>0) ) { resG.graph->next(in); }
   649 	if (!resG.graph->valid(in)) {
   650 	  forward=false;
   651 	  resG.graph->first(out, v);
   652 	  while( resG.graph->valid(out) && !(resG.resCap(*this)>0) ) { resG.graph->next(out); }
   653 	}
   654       }
   655       operator Edge() const { 
   656 //	Edge e;
   657 //	e.forward=this->forward;
   658 //	if (this->forward) e=out; else e=in;
   659 //	return e;
   660 	if (this->forward) 
   661 	  return Edge(in, this->forward); 
   662 	else 
   663 	  return Edge(out, this->forward);
   664       }
   665     };
   666 
   667     class EdgeIt {
   668       friend class ResGraphWrapper<Graph, Number, CapacityMap, FlowMap>;
   669     protected:
   670       typename Graph::EdgeIt e;
   671       bool forward;
   672     public:
   673       EdgeIt() { }
   674       EdgeIt(const Invalid& i) : e(i), forward(false) { }
   675       EdgeIt(const ResGraphWrapper<Graph, Number, CapacityMap, FlowMap>& resG) { 
   676 	forward=true;
   677 	resG.graph->first(e);
   678 	while (resG.graph->valid(e) && !(resG.resCap(*this)>0)) resG.graph->next(e);
   679 	if (!resG.graph->valid(e)) {
   680 	  forward=false;
   681 	  resG.graph->first(e);
   682 	  while (resG.graph->valid(e) && !(resG.resCap(*this)>0)) resG.graph->next(e);
   683 	}
   684       }
   685       operator Edge() const { 
   686 	return Edge(e, this->forward);
   687       }
   688     };
   689 
   690     using GraphWrapper<Graph>::first;
   691 //     NodeIt& first(NodeIt& i) const { 
   692 //       i=NodeIt(*this); return i;
   693 //     }
   694     OutEdgeIt& first(OutEdgeIt& i, const Node& p) const { 
   695       i=OutEdgeIt(*this, p); return i;
   696     }
   697 //    FIXME not tested
   698     InEdgeIt& first(InEdgeIt& i, const Node& p) const { 
   699       i=InEdgeIt(*this, p); return i;
   700     }
   701     EdgeIt& first(EdgeIt& i) const { 
   702       i=EdgeIt(*this); return i;
   703     }
   704   
   705     using GraphWrapper<Graph>::next;
   706 //    NodeIt& next(NodeIt& n) const { GraphWrapper<Graph>::next(n); return n; }
   707     OutEdgeIt& next(OutEdgeIt& e) const { 
   708       if (e.forward) {
   709 	Node v=this->graph->aNode(e.out);
   710 	this->graph->next(e.out);
   711 	while( this->graph->valid(e.out) && !(resCap(e)>0) ) { 
   712 	  this->graph->next(e.out); }
   713 	if (!this->graph->valid(e.out)) {
   714 	  e.forward=false;
   715 	  this->graph->first(e.in, v); 
   716 	  while( this->graph->valid(e.in) && !(resCap(e)>0) ) { 
   717 	    this->graph->next(e.in); }
   718 	}
   719       } else {
   720 	this->graph->next(e.in);
   721 	while( this->graph->valid(e.in) && !(resCap(e)>0) ) { 
   722 	  this->graph->next(e.in); } 
   723       }
   724       return e;
   725     }
   726 //     FIXME Not tested
   727     InEdgeIt& next(InEdgeIt& e) const { 
   728       if (e.forward) {
   729 	Node v=this->graph->aNode(e.in);
   730 	this->graph->next(e.in);
   731 	while( this->graph->valid(e.in) && !(resCap(e)>0) ) { 
   732 	  this->graph->next(e.in); }
   733 	if (!this->graph->valid(e.in)) {
   734 	  e.forward=false;
   735 	  this->graph->first(e.out, v); 
   736 	  while( this->graph->valid(e.out) && !(resCap(e)>0) ) { 
   737 	    this->graph->next(e.out); }
   738 	}
   739       } else {
   740 	this->graph->next(e.out);
   741 	while( this->graph->valid(e.out) && !(resCap(e)>0) ) { 
   742 	  this->graph->next(e.out); } 
   743       }
   744       return e;
   745     }
   746     EdgeIt& next(EdgeIt& e) const {
   747       if (e.forward) {
   748 	this->graph->next(e.e);
   749 	while( this->graph->valid(e.e) && !(resCap(e)>0) ) { 
   750 	  this->graph->next(e.e); }
   751 	if (!this->graph->valid(e.e)) {
   752 	  e.forward=false;
   753 	  this->graph->first(e.e); 
   754 	  while( this->graph->valid(e.e) && !(resCap(e)>0) ) { 
   755 	    this->graph->next(e.e); }
   756 	}
   757       } else {
   758 	this->graph->next(e.e);
   759 	while( this->graph->valid(e.e) && !(resCap(e)>0) ) { 
   760 	  this->graph->next(e.e); } 
   761       }
   762       return e;
   763     }
   764 
   765     Node tail(Edge e) const { 
   766       return ((e.forward) ? this->graph->tail(e) : this->graph->head(e)); }
   767     Node head(Edge e) const { 
   768       return ((e.forward) ? this->graph->head(e) : this->graph->tail(e)); }
   769 
   770     Node aNode(OutEdgeIt e) const { 
   771       return ((e.forward) ? this->graph->aNode(e.out) : 
   772 	      this->graph->aNode(e.in)); }
   773     Node bNode(OutEdgeIt e) const { 
   774       return ((e.forward) ? this->graph->bNode(e.out) : 
   775 	      this->graph->bNode(e.in)); }
   776 
   777     Node aNode(InEdgeIt e) const { 
   778       return ((e.forward) ? this->graph->aNode(e.in) : 
   779 	      this->graph->aNode(e.out)); }
   780     Node bNode(InEdgeIt e) const { 
   781       return ((e.forward) ? this->graph->bNode(e.in) : 
   782 	      this->graph->bNode(e.out)); }
   783 
   784 //    int nodeNum() const { return graph->nodeNum(); }
   785     //FIXME
   786     void edgeNum() const { }
   787     //int edgeNum() const { return graph->edgeNum(); }
   788 
   789 
   790 //    int id(Node v) const { return graph->id(v); }
   791 
   792     bool valid(Node n) const { return GraphWrapper<Graph>::valid(n); }
   793     bool valid(Edge e) const { 
   794       return this->graph->valid(e);
   795 	//return e.forward ? graph->valid(e.out) : graph->valid(e.in); 
   796     }
   797 
   798     void augment(const Edge& e, Number a) const {
   799       if (e.forward)  
   800 // 	flow->set(e.out, flow->get(e.out)+a);
   801 	flow->set(e, (*flow)[e]+a);
   802       else  
   803 // 	flow->set(e.in, flow->get(e.in)-a);
   804 	flow->set(e, (*flow)[e]-a);
   805     }
   806 
   807     Number resCap(const Edge& e) const { 
   808       if (e.forward) 
   809 //	return (capacity->get(e.out)-flow->get(e.out)); 
   810 	return ((*capacity)[e]-(*flow)[e]); 
   811       else 
   812 //	return (flow->get(e.in)); 
   813 	return ((*flow)[e]); 
   814     }
   815 
   816 //     Number resCap(typename Graph::OutEdgeIt out) const { 
   817 // //      return (capacity->get(out)-flow->get(out)); 
   818 //       return ((*capacity)[out]-(*flow)[out]); 
   819 //     }
   820     
   821 //     Number resCap(typename Graph::InEdgeIt in) const { 
   822 // //      return (flow->get(in)); 
   823 //       return ((*flow)[in]); 
   824 //     }
   825 
   826     template <typename T>
   827     class EdgeMap {
   828       typename Graph::template EdgeMap<T> forward_map, backward_map; 
   829     public:
   830       EdgeMap(const ResGraphWrapper<Graph, Number, CapacityMap, FlowMap>& _G) : forward_map(*(_G.graph)), backward_map(*(_G.graph)) { }
   831       EdgeMap(const ResGraphWrapper<Graph, Number, CapacityMap, FlowMap>& _G, T a) : forward_map(*(_G.graph), a), backward_map(*(_G.graph), a) { }
   832       void set(Edge e, T a) { 
   833 	if (e.forward) 
   834 	  forward_map.set(e.out, a); 
   835 	else 
   836 	  backward_map.set(e.in, a); 
   837       }
   838       T operator[](Edge e) const { 
   839 	if (e.forward) 
   840 	  return forward_map[e.out]; 
   841 	else 
   842 	  return backward_map[e.in]; 
   843       }
   844 //       T get(Edge e) const { 
   845 // 	if (e.out_or_in) 
   846 // 	  return forward_map.get(e.out); 
   847 // 	else 
   848 // 	  return backward_map.get(e.in); 
   849 //       }
   850     };
   851   };
   852 
   853   /// ErasingFirstGraphWrapper for blocking flows.
   854 
   855   /// ErasingFirstGraphWrapper for blocking flows.
   856   ///
   857   ///\author Marton Makai
   858   template<typename Graph, typename FirstOutEdgesMap>
   859   class ErasingFirstGraphWrapper : public GraphWrapper<Graph> {
   860   protected:
   861     FirstOutEdgesMap* first_out_edges;
   862   public:
   863     ErasingFirstGraphWrapper(Graph& _graph, 
   864 			     FirstOutEdgesMap& _first_out_edges) : 
   865       GraphWrapper<Graph>(_graph), first_out_edges(&_first_out_edges) { }  
   866 
   867     typedef typename GraphWrapper<Graph>::Node Node;
   868 //     class NodeIt { 
   869 //       friend class GraphWrapper<Graph>;
   870 //       friend class ErasingFirstGraphWrapper<Graph, FirstOutEdgesMap>;
   871 //       typename Graph::NodeIt n;
   872 //      public:
   873 //       NodeIt() { }
   874 //       NodeIt(const typename Graph::NodeIt& _n) : n(_n) { }
   875 //       NodeIt(const Invalid& i) : n(i) { }
   876 //       NodeIt(const ErasingFirstGraphWrapper<Graph, FirstOutEdgesMap>& _G) : 
   877 // 	n(*(_G.graph)) { }
   878 //       operator Node() const { return Node(typename Graph::Node(n)); }
   879 //     };
   880     typedef typename GraphWrapper<Graph>::Edge Edge;
   881     class OutEdgeIt { 
   882       friend class GraphWrapper<Graph>;
   883       friend class ErasingFirstGraphWrapper<Graph, FirstOutEdgesMap>;
   884 //      typedef typename Graph::OutEdgeIt GraphOutEdgeIt;
   885       typename Graph::OutEdgeIt e;
   886     public:
   887       OutEdgeIt() { }
   888       OutEdgeIt(const typename Graph::OutEdgeIt& _e) : e(_e) { }
   889       OutEdgeIt(const Invalid& i) : e(i) { }
   890       OutEdgeIt(const ErasingFirstGraphWrapper<Graph, FirstOutEdgesMap>& _G, 
   891 		const Node& _n) : 
   892 	e((*_G.first_out_edges)[_n]) { }
   893       operator Edge() const { return Edge(typename Graph::Edge(e)); }
   894     };
   895     class InEdgeIt { 
   896       friend class GraphWrapper<Graph>;
   897       friend class ErasingFirstGraphWrapper<Graph, FirstOutEdgesMap>;
   898 //      typedef typename Graph::InEdgeIt GraphInEdgeIt;
   899       typename Graph::InEdgeIt e;
   900     public:
   901       InEdgeIt() { }
   902       InEdgeIt(const typename Graph::InEdgeIt& _e) : e(_e) { }
   903       InEdgeIt(const Invalid& i) : e(i) { }
   904       InEdgeIt(const ErasingFirstGraphWrapper<Graph, FirstOutEdgesMap>& _G, 
   905 	       const Node& _n) : 
   906 	e(*(_G.graph), typename Graph::Node(_n)) { }
   907       operator Edge() const { return Edge(typename Graph::Edge(e)); }
   908     };
   909     //typedef typename Graph::SymEdgeIt SymEdgeIt;
   910     class EdgeIt { 
   911       friend class GraphWrapper<Graph>;
   912       friend class ErasingFirstGraphWrapper<Graph, FirstOutEdgesMap>;
   913 //      typedef typename Graph::EdgeIt GraphEdgeIt;
   914       typename Graph::EdgeIt e;
   915     public:
   916       EdgeIt() { }
   917       EdgeIt(const typename Graph::EdgeIt& _e) : e(_e) { }
   918       EdgeIt(const Invalid& i) : e(i) { }
   919       EdgeIt(const ErasingFirstGraphWrapper<Graph, FirstOutEdgesMap>& _G) : 
   920 	e(*(_G.graph)) { }
   921       operator Edge() const { return Edge(typename Graph::Edge(e)); }
   922     };
   923 
   924     using GraphWrapper<Graph>::first;
   925 //     NodeIt& first(NodeIt& i) const { 
   926 //       i=NodeIt(*this); return i;
   927 //     }
   928     OutEdgeIt& first(OutEdgeIt& i, const Node& p) const { 
   929       i=OutEdgeIt(*this, p); return i;
   930     }
   931     InEdgeIt& first(InEdgeIt& i, const Node& p) const { 
   932       i=InEdgeIt(*this, p); return i;
   933     }
   934     EdgeIt& first(EdgeIt& i) const { 
   935       i=EdgeIt(*this); return i;
   936     }
   937 
   938     using GraphWrapper<Graph>::next;
   939 //    NodeIt& next(NodeIt& i) const { graph->next(i.n); return i; }
   940     OutEdgeIt& next(OutEdgeIt& i) const { this->graph->next(i.e); return i; }
   941     InEdgeIt& next(InEdgeIt& i) const { this->graph->next(i.e); return i; }
   942     EdgeIt& next(EdgeIt& i) const { this->graph->next(i.e); return i; }    
   943     
   944     Node aNode(const OutEdgeIt& e) const { 
   945       return Node(this->graph->aNode(e.e)); }
   946     Node aNode(const InEdgeIt& e) const { 
   947       return Node(this->graph->aNode(e.e)); }
   948     Node bNode(const OutEdgeIt& e) const { 
   949       return Node(this->graph->bNode(e.e)); }
   950     Node bNode(const InEdgeIt& e) const { 
   951       return Node(this->graph->bNode(e.e)); }
   952 
   953     void erase(const OutEdgeIt& e) const {
   954       OutEdgeIt f=e;
   955       this->next(f);
   956       first_out_edges->set(this->tail(e), f.e);
   957     }
   958   };
   959 
   960   ///@}
   961 
   962 } //namespace hugo
   963 
   964 
   965 #endif //HUGO_GRAPH_WRAPPER_H
   966