src/hugo/smart_graph.h
author alpar
Mon, 19 Jul 2004 13:32:28 +0000
changeset 709 7a518df79892
parent 590 5c1465127b79
child 713 57c0b110b31e
permissions -rw-r--r--
docfix
     1 // -*- mode:C++ -*-
     2 
     3 #ifndef HUGO_SMART_GRAPH_H
     4 #define HUGO_SMART_GRAPH_H
     5 
     6 ///\ingroup graphs
     7 ///\file
     8 ///\brief SmartGraph and SymSmartGraph classes.
     9 
    10 #include <vector>
    11 #include <limits.h>
    12 
    13 #include <hugo/invalid.h>
    14 
    15 namespace hugo {
    16 
    17 /// \addtogroup graphs
    18 /// @{
    19   class SymSmartGraph;
    20 
    21   ///A smart graph class.
    22 
    23   ///This is a simple and fast graph implementation.
    24   ///It is also quite memory efficient, but at the price
    25   ///that <b> it does not support node and edge deletion</b>.
    26   ///It conforms to the graph interface documented under
    27   ///the description of \ref GraphSkeleton.
    28   ///\sa \ref GraphSkeleton.
    29   ///
    30   ///\todo Some member functions could be \c static.
    31   ///\author Alpar Juttner
    32   class SmartGraph {
    33 
    34     struct NodeT 
    35     {
    36       int first_in,first_out;      
    37       NodeT() : first_in(-1), first_out(-1) {}
    38     };
    39     struct EdgeT 
    40     {
    41       int head, tail, next_in, next_out;      
    42       //FIXME: is this necessary?
    43       EdgeT() : next_in(-1), next_out(-1) {}  
    44     };
    45 
    46     std::vector<NodeT> nodes;
    47 
    48     std::vector<EdgeT> edges;
    49     
    50     protected:
    51     
    52     template <typename Key> class DynMapBase
    53     {
    54     protected:
    55       const SmartGraph* G; 
    56     public:
    57       virtual void add(const Key k) = 0;
    58       virtual void erase(const Key k) = 0;
    59       DynMapBase(const SmartGraph &_G) : G(&_G) {}
    60       virtual ~DynMapBase() {}
    61       friend class SmartGraph;
    62     };
    63     
    64   public:
    65     template <typename T> class EdgeMap;
    66     template <typename T> class NodeMap;
    67 
    68     class Node;
    69     class Edge;
    70 
    71     //  protected:
    72     // HELPME:
    73   protected:
    74     ///\bug It must be public because of SymEdgeMap.
    75     ///
    76     mutable std::vector<DynMapBase<Node> * > dyn_node_maps;
    77     ///\bug It must be public because of SymEdgeMap.
    78     ///
    79     mutable std::vector<DynMapBase<Edge> * > dyn_edge_maps;
    80     
    81   public:
    82 
    83 
    84     class NodeIt;
    85     class EdgeIt;
    86     class OutEdgeIt;
    87     class InEdgeIt;
    88     
    89     template <typename T> class NodeMap;
    90     template <typename T> class EdgeMap;
    91     
    92   public:
    93 
    94     SmartGraph() : nodes(), edges() { }
    95     SmartGraph(const SmartGraph &_g) : nodes(_g.nodes), edges(_g.edges) { }
    96     
    97     ~SmartGraph()
    98     {
    99       for(std::vector<DynMapBase<Node> * >::iterator i=dyn_node_maps.begin();
   100 	  i!=dyn_node_maps.end(); ++i) (**i).G=NULL;
   101       for(std::vector<DynMapBase<Edge> * >::iterator i=dyn_edge_maps.begin();
   102 	  i!=dyn_edge_maps.end(); ++i) (**i).G=NULL;
   103     }
   104 
   105     int nodeNum() const { return nodes.size(); }  //FIXME: What is this?
   106     int edgeNum() const { return edges.size(); }  //FIXME: What is this?
   107 
   108     ///\bug This function does something different than
   109     ///its name would suggests...
   110     int maxNodeId() const { return nodes.size(); }  //FIXME: What is this?
   111     ///\bug This function does something different than
   112     ///its name would suggests...
   113     int maxEdgeId() const { return edges.size(); }  //FIXME: What is this?
   114 
   115     Node tail(Edge e) const { return edges[e.n].tail; }
   116     Node head(Edge e) const { return edges[e.n].head; }
   117 
   118     Node aNode(OutEdgeIt e) const { return edges[e.n].tail; }
   119     Node aNode(InEdgeIt e) const { return edges[e.n].head; }
   120 
   121     Node bNode(OutEdgeIt e) const { return edges[e.n].head; }
   122     Node bNode(InEdgeIt e) const { return edges[e.n].tail; }
   123 
   124     NodeIt& first(NodeIt& v) const { 
   125       v=NodeIt(*this); return v; }
   126     EdgeIt& first(EdgeIt& e) const { 
   127       e=EdgeIt(*this); return e; }
   128     OutEdgeIt& first(OutEdgeIt& e, const Node v) const { 
   129       e=OutEdgeIt(*this,v); return e; }
   130     InEdgeIt& first(InEdgeIt& e, const Node v) const { 
   131       e=InEdgeIt(*this,v); return e; }
   132 
   133 //     template< typename It >
   134 //     It first() const { It e; first(e); return e; }
   135 
   136 //     template< typename It >
   137 //     It first(Node v) const { It e; first(e,v); return e; }
   138 
   139     bool valid(Edge e) const { return e.n!=-1; }
   140     bool valid(Node n) const { return n.n!=-1; }
   141     
   142     ///\deprecated Use
   143     ///\code
   144     ///  e=INVALID;
   145     ///\endcode
   146     ///instead.
   147     void setInvalid(Edge &e) { e.n=-1; }
   148     ///\deprecated Use
   149     ///\code
   150     ///  e=INVALID;
   151     ///\endcode
   152     ///instead.
   153     void setInvalid(Node &n) { n.n=-1; }
   154     
   155     template <typename It> It getNext(It it) const
   156     { It tmp(it); return next(tmp); }
   157 
   158     NodeIt& next(NodeIt& it) const { 
   159       it.n=(it.n+2)%(nodes.size()+1)-1; 
   160       return it; 
   161     }
   162     OutEdgeIt& next(OutEdgeIt& it) const
   163     { it.n=edges[it.n].next_out; return it; }
   164     InEdgeIt& next(InEdgeIt& it) const
   165     { it.n=edges[it.n].next_in; return it; }
   166     EdgeIt& next(EdgeIt& it) const { --it.n; return it; }
   167 
   168     int id(Node v) const { return v.n; }
   169     int id(Edge e) const { return e.n; }
   170 
   171     Node addNode() {
   172       Node n; n.n=nodes.size();
   173       nodes.push_back(NodeT()); //FIXME: Hmmm...
   174 
   175       for(std::vector<DynMapBase<Node> * >::iterator i=dyn_node_maps.begin();
   176 	  i!=dyn_node_maps.end(); ++i) (**i).add(n);
   177 
   178       return n;
   179     }
   180     
   181     Edge addEdge(Node u, Node v) {
   182       Edge e; e.n=edges.size(); edges.push_back(EdgeT()); //FIXME: Hmmm...
   183       edges[e.n].tail=u.n; edges[e.n].head=v.n;
   184       edges[e.n].next_out=nodes[u.n].first_out;
   185       edges[e.n].next_in=nodes[v.n].first_in;
   186       nodes[u.n].first_out=nodes[v.n].first_in=e.n;
   187 
   188       for(std::vector<DynMapBase<Edge> * >::iterator i=dyn_edge_maps.begin();
   189 	  i!=dyn_edge_maps.end(); ++i) (**i).add(e);
   190 
   191       return e;
   192     }
   193 
   194     void clear() {nodes.clear();edges.clear();}
   195 
   196     class Node {
   197       friend class SmartGraph;
   198       template <typename T> friend class NodeMap;
   199       
   200       friend class Edge;
   201       friend class OutEdgeIt;
   202       friend class InEdgeIt;
   203       friend class SymEdge;
   204 
   205     protected:
   206       int n;
   207       friend int SmartGraph::id(Node v) const; 
   208       Node(int nn) {n=nn;}
   209     public:
   210       Node() {}
   211       Node (Invalid) { n=-1; }
   212       bool operator==(const Node i) const {return n==i.n;}
   213       bool operator!=(const Node i) const {return n!=i.n;}
   214       bool operator<(const Node i) const {return n<i.n;}
   215     };
   216     
   217     class NodeIt : public Node {
   218       friend class SmartGraph;
   219     public:
   220       NodeIt() : Node() { }
   221       NodeIt(Invalid i) : Node(i) { }
   222       NodeIt(const SmartGraph& G) : Node(G.nodes.size()?0:-1) { }
   223       ///\todo Undocumented conversion Node -\> NodeIt.
   224       NodeIt(const SmartGraph& G, const Node &n) : Node(n) { }
   225     };
   226 
   227     class Edge {
   228       friend class SmartGraph;
   229       template <typename T> friend class EdgeMap;
   230 
   231       //template <typename T> friend class SymSmartGraph::SymEdgeMap;      
   232       //friend Edge SymSmartGraph::opposite(Edge) const;
   233       
   234       friend class Node;
   235       friend class NodeIt;
   236     protected:
   237       int n;
   238       friend int SmartGraph::id(Edge e) const;
   239 
   240     public:
   241       /// An Edge with id \c n.
   242 
   243       /// \bug It should be
   244       /// obtained by a member function of the Graph.
   245       Edge(int nn) {n=nn;}
   246       Edge() { }
   247       Edge (Invalid) { n=-1; }
   248       bool operator==(const Edge i) const {return n==i.n;}
   249       bool operator!=(const Edge i) const {return n!=i.n;}
   250       bool operator<(const Edge i) const {return n<i.n;}
   251       ///\bug This is a workaround until somebody tells me how to
   252       ///make class \c SymSmartGraph::SymEdgeMap friend of Edge
   253       int &idref() {return n;}
   254       const int &idref() const {return n;}
   255     };
   256     
   257     class EdgeIt : public Edge {
   258       friend class SmartGraph;
   259     public:
   260       EdgeIt(const SmartGraph& G) : Edge(G.edges.size()-1) { }
   261       EdgeIt (Invalid i) : Edge(i) { }
   262       EdgeIt() : Edge() { }
   263       ///\bug This is a workaround until somebody tells me how to
   264       ///make class \c SymSmartGraph::SymEdgeMap friend of Edge
   265       int &idref() {return n;}
   266     };
   267     
   268     class OutEdgeIt : public Edge {
   269       friend class SmartGraph;
   270     public: 
   271       OutEdgeIt() : Edge() { }
   272       OutEdgeIt (Invalid i) : Edge(i) { }
   273 
   274       OutEdgeIt(const SmartGraph& G,const Node v)
   275 	: Edge(G.nodes[v.n].first_out) {}
   276     };
   277     
   278     class InEdgeIt : public Edge {
   279       friend class SmartGraph;
   280     public: 
   281       InEdgeIt() : Edge() { }
   282       InEdgeIt (Invalid i) : Edge(i) { }
   283       InEdgeIt(const SmartGraph& G,Node v) :Edge(G.nodes[v.n].first_in){}
   284     };
   285 
   286     template <typename T> class NodeMap : public DynMapBase<Node>
   287     {
   288       std::vector<T> container;
   289 
   290     public:
   291       typedef T ValueType;
   292       typedef Node KeyType;
   293 
   294       NodeMap(const SmartGraph &_G) :
   295 	DynMapBase<Node>(_G), container(_G.maxNodeId())
   296       {
   297 	G->dyn_node_maps.push_back(this);
   298       }
   299       NodeMap(const SmartGraph &_G,const T &t) :
   300 	DynMapBase<Node>(_G), container(_G.maxNodeId(),t)
   301       {
   302 	G->dyn_node_maps.push_back(this);
   303       }
   304       
   305       NodeMap(const NodeMap<T> &m) :
   306  	DynMapBase<Node>(*m.G), container(m.container)
   307       {
   308  	G->dyn_node_maps.push_back(this);
   309       }
   310 
   311       template<typename TT> friend class NodeMap;
   312  
   313       ///\todo It can copy between different types.
   314       ///\todo We could use 'copy'
   315       template<typename TT> NodeMap(const NodeMap<TT> &m) :
   316 	DynMapBase<Node>(*m.G), container(m.container.size())
   317       {
   318 	G->dyn_node_maps.push_back(this);
   319 	typename std::vector<TT>::const_iterator i;
   320 	for(typename std::vector<TT>::const_iterator i=m.container.begin();
   321 	    i!=m.container.end();
   322 	    i++)
   323 	  container.push_back(*i);
   324       }
   325       ~NodeMap()
   326       {
   327 	if(G) {
   328 	  std::vector<DynMapBase<Node>* >::iterator i;
   329 	  for(i=G->dyn_node_maps.begin();
   330 	      i!=G->dyn_node_maps.end() && *i!=this; ++i) ;
   331 	  //if(*i==this) G->dyn_node_maps.erase(i); //FIXME: Way too slow...
   332 	  //A better way to do that: (Is this really important?)
   333 	  if(*i==this) {
   334 	    *i=G->dyn_node_maps.back();
   335 	    G->dyn_node_maps.pop_back();
   336 	  }
   337 	}
   338       }
   339 
   340       void add(const Node k) 
   341       {
   342 	if(k.n>=int(container.size())) container.resize(k.n+1);
   343       }
   344 
   345       void erase(const Node) { }
   346       
   347       void set(Node n, T a) { container[n.n]=a; }
   348       //'T& operator[](Node n)' would be wrong here
   349       typename std::vector<T>::reference
   350       operator[](Node n) { return container[n.n]; }
   351       //'const T& operator[](Node n)' would be wrong here
   352       typename std::vector<T>::const_reference 
   353       operator[](Node n) const { return container[n.n]; }
   354 
   355       ///\warning There is no safety check at all!
   356       ///Using operator = between maps attached to different graph may
   357       ///cause serious problem.
   358       ///\todo Is this really so?
   359       ///\todo It can copy between different types.
   360       const NodeMap<T>& operator=(const NodeMap<T> &m)
   361       {
   362 	container = m.container;
   363 	return *this;
   364       }
   365       template<typename TT>
   366       const NodeMap<T>& operator=(const NodeMap<TT> &m)
   367       {
   368 	std::copy(m.container.begin(), m.container.end(), container.begin());
   369 	return *this;
   370       }
   371       
   372       void update() {}    //Useless for Dynamic Maps
   373       void update(T a) {}  //Useless for Dynamic Maps
   374     };
   375     
   376     template <typename T> class EdgeMap : public DynMapBase<Edge>
   377     {
   378       std::vector<T> container;
   379 
   380     public:
   381       typedef T ValueType;
   382       typedef Edge KeyType;
   383 
   384       EdgeMap(const SmartGraph &_G) :
   385 	DynMapBase<Edge>(_G), container(_G.maxEdgeId())
   386       {
   387 	//FIXME: What if there are empty Id's?
   388 	//FIXME: Can I use 'this' in a constructor?
   389 	G->dyn_edge_maps.push_back(this);
   390       }
   391       EdgeMap(const SmartGraph &_G,const T &t) :
   392 	DynMapBase<Edge>(_G), container(_G.maxEdgeId(),t)
   393       {
   394 	G->dyn_edge_maps.push_back(this);
   395       } 
   396       EdgeMap(const EdgeMap<T> &m) :
   397  	DynMapBase<Edge>(*m.G), container(m.container)
   398       {
   399  	G->dyn_edge_maps.push_back(this);
   400       }
   401 
   402       template<typename TT> friend class EdgeMap;
   403 
   404       ///\todo It can copy between different types.
   405       template<typename TT> EdgeMap(const EdgeMap<TT> &m)
   406 	: DynMapBase<Edge>(*m.G), container(m.container.size())
   407       {
   408 	G->dyn_edge_maps.push_back(this);
   409 	typename std::vector<TT>::const_iterator i;
   410 	for(typename std::vector<TT>::const_iterator i=m.container.begin();
   411 	    i!=m.container.end();
   412 	    i++)
   413 	  container.push_back(*i);
   414       }
   415       ~EdgeMap()
   416       {
   417 	if(G) {
   418 	  std::vector<DynMapBase<Edge>* >::iterator i;
   419 	  for(i=G->dyn_edge_maps.begin();
   420 	      i!=G->dyn_edge_maps.end() && *i!=this; ++i) ;
   421 	  //if(*i==this) G->dyn_edge_maps.erase(i); //Way too slow...
   422 	  //A better way to do that: (Is this really important?)
   423 	  if(*i==this) {
   424 	    *i=G->dyn_edge_maps.back();
   425 	    G->dyn_edge_maps.pop_back();
   426 	  }
   427 	}
   428       }
   429       
   430       void add(const Edge k) 
   431       {
   432 	if(k.n>=int(container.size())) container.resize(k.n+1);
   433       }
   434       void erase(const Edge) { }
   435       
   436       void set(Edge n, T a) { container[n.n]=a; }
   437       //T get(Edge n) const { return container[n.n]; }
   438       typename std::vector<T>::reference
   439       operator[](Edge n) { return container[n.n]; }
   440       typename std::vector<T>::const_reference
   441       operator[](Edge n) const { return container[n.n]; }
   442 
   443       ///\warning There is no safety check at all!
   444       ///Using operator = between maps attached to different graph may
   445       ///cause serious problem.
   446       ///\todo Is this really so?
   447       ///\todo It can copy between different types.
   448       const EdgeMap<T>& operator=(const EdgeMap<T> &m)
   449       {
   450 	container = m.container;
   451 	return *this;
   452       }
   453       template<typename TT>
   454       const EdgeMap<T>& operator=(const EdgeMap<TT> &m)
   455       {
   456 	std::copy(m.container.begin(), m.container.end(), container.begin());
   457 	return *this;
   458       }
   459       
   460       void update() {}    //Useless for DynMaps
   461       void update(T a) {}  //Useless for DynMaps
   462     };
   463 
   464   };
   465 
   466   ///Graph for bidirectional edges.
   467 
   468   ///The purpose of this graph structure is to handle graphs
   469   ///having bidirectional edges. Here the function \c addEdge(u,v) adds a pair
   470   ///of oppositely directed edges.
   471   ///There is a new edge map type called
   472   ///\ref SymSmartGraph::SymEdgeMap "SymEdgeMap"
   473   ///that complements this
   474   ///feature by
   475   ///storing shared values for the edge pairs. The usual
   476   ///\ref GraphSkeleton::EdgeMap "EdgeMap"
   477   ///can be used
   478   ///as well.
   479   ///
   480   ///The oppositely directed edge can also be obtained easily
   481   ///using \ref opposite.
   482   ///\warning It shares the similarity with \ref SmartGraph that
   483   ///it is not possible to delete edges or nodes from the graph.
   484   //\sa \ref SmartGraph.
   485 
   486   class SymSmartGraph : public SmartGraph
   487   {
   488   public:
   489     template<typename T> class SymEdgeMap;
   490     template<typename T> friend class SymEdgeMap;
   491 
   492     SymSmartGraph() : SmartGraph() { }
   493     SymSmartGraph(const SmartGraph &_g) : SmartGraph(_g) { }
   494     ///Adds a pair of oppositely directed edges to the graph.
   495     Edge addEdge(Node u, Node v)
   496     {
   497       Edge e = SmartGraph::addEdge(u,v);
   498       SmartGraph::addEdge(v,u);
   499       return e;
   500     }
   501 
   502     ///The oppositely directed edge.
   503 
   504     ///Returns the oppositely directed
   505     ///pair of the edge \c e.
   506     Edge opposite(Edge e) const
   507     {
   508       Edge f;
   509       f.idref() = e.idref() - 2*(e.idref()%2) + 1;
   510       return f;
   511     }
   512     
   513     ///Common data storage for the edge pairs.
   514 
   515     ///This map makes it possible to store data shared by the oppositely
   516     ///directed pairs of edges.
   517     template <typename T> class SymEdgeMap : public DynMapBase<Edge>
   518     {
   519       std::vector<T> container;
   520       
   521     public:
   522       typedef T ValueType;
   523       typedef Edge KeyType;
   524 
   525       SymEdgeMap(const SymSmartGraph &_G) :
   526 	DynMapBase<Edge>(_G), container(_G.maxEdgeId()/2)
   527       {
   528 	static_cast<const SymSmartGraph*>(G)->dyn_edge_maps.push_back(this);
   529       }
   530       SymEdgeMap(const SymSmartGraph &_G,const T &t) :
   531 	DynMapBase<Edge>(_G), container(_G.maxEdgeId()/2,t)
   532       {
   533 	G->dyn_edge_maps.push_back(this);
   534       }
   535 
   536       SymEdgeMap(const SymEdgeMap<T> &m) :
   537  	DynMapBase<SymEdge>(*m.G), container(m.container)
   538       {
   539  	G->dyn_node_maps.push_back(this);
   540       }
   541 
   542       //      template<typename TT> friend class SymEdgeMap;
   543 
   544       ///\todo It can copy between different types.
   545       ///
   546 
   547       template<typename TT> SymEdgeMap(const SymEdgeMap<TT> &m)
   548 	: DynMapBase<SymEdge>(*m.G), container(m.container.size())
   549       {
   550 	G->dyn_node_maps.push_back(this);
   551 	typename std::vector<TT>::const_iterator i;
   552 	for(typename std::vector<TT>::const_iterator i=m.container.begin();
   553 	    i!=m.container.end();
   554 	    i++)
   555 	  container.push_back(*i);
   556       }
   557  
   558       ~SymEdgeMap()
   559       {
   560 	if(G) {
   561 	  std::vector<DynMapBase<Edge>* >::iterator i;
   562 	  for(i=static_cast<const SymSmartGraph*>(G)->dyn_edge_maps.begin();
   563 	      i!=static_cast<const SymSmartGraph*>(G)->dyn_edge_maps.end()
   564 		&& *i!=this; ++i) ;
   565 	  //if(*i==this) G->dyn_edge_maps.erase(i); //Way too slow...
   566 	  //A better way to do that: (Is this really important?)
   567 	  if(*i==this) {
   568 	    *i=static_cast<const SymSmartGraph*>(G)->dyn_edge_maps.back();
   569 	    static_cast<const SymSmartGraph*>(G)->dyn_edge_maps.pop_back();
   570 	  }
   571 	}
   572       }
   573       
   574       void add(const Edge k) 
   575       {
   576 	if(!k.idref()%2&&k.idref()/2>=int(container.size()))
   577 	  container.resize(k.idref()/2+1);
   578       }
   579       void erase(const Edge k) { }
   580       
   581       void set(Edge n, T a) { container[n.idref()/2]=a; }
   582       //T get(Edge n) const { return container[n.idref()/2]; }
   583       typename std::vector<T>::reference
   584       operator[](Edge n) { return container[n.idref()/2]; }
   585       typename std::vector<T>::const_reference
   586       operator[](Edge n) const { return container[n.idref()/2]; }
   587 
   588       ///\warning There is no safety check at all!
   589       ///Using operator = between maps attached to different graph may
   590       ///cause serious problem.
   591       ///\todo Is this really so?
   592       ///\todo It can copy between different types.
   593       const SymEdgeMap<T>& operator=(const SymEdgeMap<T> &m)
   594       {
   595 	container = m.container;
   596 	return *this;
   597       }
   598       template<typename TT>
   599       const SymEdgeMap<T>& operator=(const SymEdgeMap<TT> &m)
   600       {
   601 	std::copy(m.container.begin(), m.container.end(), container.begin());
   602 	return *this;
   603       }
   604       
   605       void update() {}    //Useless for DynMaps
   606       void update(T a) {}  //Useless for DynMaps
   607 
   608     };
   609 
   610   };
   611   
   612   /// @}  
   613 
   614 } //namespace hugo
   615 
   616 
   617 
   618 
   619 #endif //HUGO_SMART_GRAPH_H