marci@325: // -*- c++ -*-
alpar@921: #ifndef LEMON_GRAPH_H
alpar@921: #define LEMON_GRAPH_H
marci@325: 
marci@325: ///\file
marci@651: ///\brief Declaration of GraphConcept.
marci@325: 
alpar@921: #include <lemon/invalid.h>
marci@325: 
alpar@921: namespace lemon {
marci@325: 
marci@651:   /// @defgroup empty_graph The GraphConcept class
marci@332:   /// @{
marci@325: 
marci@325:   /// An empty graph class.
marci@325:   
marci@325:   /// This class provides all the common features of a graph structure,
marci@325:   /// however completely without implementations and real data structures
marci@325:   /// behind the interface.
marci@325:   /// All graph algorithms should compile with this class, but it will not
marci@325:   /// run properly, of course.
marci@325:   ///
marci@325:   /// It can be used for checking the interface compatibility,
marci@325:   /// or it can serve as a skeleton of a new graph structure.
marci@325:   /// 
marci@325:   /// Also, you will find here the full documentation of a certain graph
marci@325:   /// feature, the documentation of a real graph imlementation
marci@325:   /// like @ref ListGraph or
marci@325:   /// @ref SmartGraph will just refer to this structure.
marci@651:   class GraphConcept
marci@325:   {
marci@325:   public:
marci@325:     /// Defalult constructor.
marci@651:     GraphConcept() { }
marci@325: 
marci@651:     /// \brief Copy consructor.
marci@651:     /// 
marci@651:     /// \todo It is not clear, what we expect from a copy constructor.
marci@651:     /// E.g. How to assign the nodes/edges to each other? What about maps?
marci@651:     GraphConcept(const GraphConcept&) { }
marci@325: 
marci@651:     /// \brief The base type of the node iterators.
marci@651:     ///
marci@325:     /// This is the base type of each node iterators,
marci@325:     /// thus each kind of node iterator will convert to this.
marci@651:     /// Sometimes it is said to be a trivial iterator.
marci@325:     class Node {
marci@325:     public:
marci@325:       /// @warning The default constructor sets the iterator
marci@325:       /// to an undefined value.
marci@651:       Node() { }   //FIXME
marci@325: 
marci@651:       // /// Copy constructor.
marci@651:       // Node(const Node&) { }
marci@651: 
marci@651:       /// \brief Invalid constructor \& conversion.
marci@651:       /// 
marci@325:       /// This constructor initializes the iterator to be invalid.
marci@325:       /// \sa Invalid for more details.
marci@651:       Node(const Invalid&) { }
marci@651:       
marci@325:       /// Two iterators are equal if and only if they point to the
marci@325:       /// same object or both are invalid.
marci@325:       bool operator==(Node n) const { return true; }
marci@325: 
marci@325:       /// \sa \ref operator==(Node n)
marci@325:       ///
marci@325:       bool operator!=(Node n) const { return true; }
marci@325: 
marci@325:       bool operator<(Node n) const { return true; }
marci@325:     };
marci@325:     
marci@325:     /// The base type of the edge iterators.
marci@325:     class Edge {
marci@325:     public:
marci@325:       /// @warning The default constructor sets the iterator
marci@325:       /// to an undefined value.
marci@651:       Edge() { }   //FIXME
marci@651: 
marci@651:       // /// Copy constructor.
marci@651:       // Edge(const Edge&) { }
marci@651: 
marci@325:       /// Initialize the iterator to be invalid
marci@651:       Edge(const Invalid&) { }
marci@325:       /// Two iterators are equal if and only if they point to the
marci@325:       /// same object or both are invalid.
marci@325:       bool operator==(Edge n) const { return true; }
marci@325:       bool operator!=(Edge n) const { return true; }
marci@325:       bool operator<(Edge n) const { return true; }
marci@325:     };
marci@325:     
marci@325:     //  class SymEdgeIt : public Edge {};
marci@325: 
marci@325: 
marci@325:     //  SymEdgeIt &first(SymEdgeIt &, Node) const { return i;}
marci@325: 
marci@325: //     Node getNext(Node) const {}
marci@325: //     InEdgeIt getNext(InEdgeIt) const {}
marci@325: //     OutEdgeIt getNext(OutEdgeIt) const {}
marci@325: //     //SymEdgeIt getNext(SymEdgeIt) const {}
marci@325: //     EdgeIt getNext(EdgeIt) const {}
marci@325: 
marci@325:     //SymEdgeIt &next(SymEdgeIt &) const {}
marci@325: 
marci@651: 
marci@651:     /// Gives back the head node of an edge.
marci@651:     Node head(const Edge&) const { return INVALID; }
marci@651:     /// Gives back the tail node of an edge.
marci@651:     Node tail(const Edge&) const { return INVALID; }
marci@325:   
marci@325:     //   Node aNode(SymEdgeIt) const {}
marci@325:     //   Node bNode(SymEdgeIt) const {}
marci@325: 
marci@651:     /// \brief Checks if a node iterator is valid
marci@651:     /// 
marci@651:     /// \todo Maybe, it would be better if iterator converted to
marci@651:     /// bool directly, as Jacint prefers.
marci@651:     bool valid(const Node&) const { return true; }
marci@651:     /// \brief Checks if an edge iterator is valid
marci@651:     /// 
marci@651:     /// \todo Maybe, it would be better if iterator converted to
marci@651:     /// bool directly, as Jacint prefers.
marci@651:     bool valid(const Edge&) const { return true; }
marci@325: 
marci@651:     /// \brief Gives back the \e id of a node.
marci@651:     /// 
marci@651:     /// \warning Not all graph structures provide this feature.
marci@325:     ///
marci@651:     int id(const Node&) const { return 0; }
marci@651:     /// \brief Gives back the \e id of an edge.
marci@325:     ///
marci@651:     /// \warning Not all graph structures provide this feature.
marci@651:     ///
marci@651:     int id(const Edge&) const { return 0; }
marci@325: 
marci@325:     //void setInvalid(Node &) const {};
marci@325:     //void setInvalid(Edge &) const {};
marci@325:   
marci@651:     /// \brief Add a new node to the graph.
marci@651:     ///
marci@325:     /// \return the new node.
marci@651:     Node addNode() { return INVALID; }
marci@651:     /// \brief Add a new edge to the graph.
marci@325:     ///
marci@651:     /// Add a new edge to the graph with tail node \c tail
marci@651:     /// and head node \c head.
marci@651:     /// \return the new edge.
marci@651:     Edge addEdge(const Node& tail, const Node& head) { return INVALID; }
marci@325:     
marci@651:     /// \brief Resets the graph.
marci@651:     /// 
marci@325:     /// This function deletes all edges and nodes of the graph.
marci@325:     /// It also frees the memory allocated to store them.
marci@651:     /// \todo What happens with the maps?
marci@651:     void clear() { }
marci@325: 
marci@651:     /// Read/write/reference map of the nodes to type \c T.
marci@325: 
marci@651:     /// Read/write/reference map of the nodes to type \c T.
marci@651:     /// \sa MemoryMapConcept
marci@325:     /// \todo We may need copy constructor
marci@325:     /// \todo We may need conversion from other nodetype
marci@325:     /// \todo We may need operator=
marci@325:     /// \warning Making maps that can handle bool type (NodeMap<bool>)
marci@325:     /// needs extra attention!
marci@325: 
marci@325:     template<class T> class NodeMap
marci@325:     {
marci@325:     public:
marci@325:       typedef T ValueType;
marci@325:       typedef Node KeyType;
marci@325: 
marci@651:       NodeMap(const GraphConcept& g) { }
marci@651:       NodeMap(const GraphConcept& g, T t) { }
marci@325: 
marci@651:       template<typename TT> NodeMap(const NodeMap<TT>& m) { }
marci@325: 
marci@325:       /// Sets the value of a node.
marci@325: 
marci@325:       /// Sets the value associated with node \c i to the value \c t.
marci@325:       ///
marci@325:       void set(Node i, T t) {}
marci@325:       /// Gets the value of a node.
marci@325:       T get(Node i) const {return *(T*)0;}  //FIXME: Is it necessary
marci@325:       T &operator[](Node i) {return *(T*)0;}
marci@325:       const T &operator[](Node i) const {return *(T*)0;}
marci@325: 
marci@325:       /// Updates the map if the graph has been changed
marci@325: 
marci@325:       /// \todo Do we need this?
marci@325:       ///
marci@651:       void update() { }
marci@651:       //void update(T a) { }   //FIXME: Is it necessary
marci@325:     };
marci@325: 
marci@325:     ///Read/write/reference map of the edges to type \c T.
marci@325: 
marci@651:     /// Read/write/reference map of the edges to type \c T.
marci@651:     /// It behaves exactly in the same way as \ref NodeMap.
marci@325:     /// \sa NodeMap
marci@651:     /// \sa MemoryMapConcept
marci@325:     /// \todo We may need copy constructor
marci@325:     /// \todo We may need conversion from other edgetype
marci@325:     /// \todo We may need operator=
marci@325:     template<class T> class EdgeMap
marci@325:     {
marci@325:     public:
marci@325:       typedef T ValueType;
marci@325:       typedef Edge KeyType;
marci@325: 
marci@651:       EdgeMap(const GraphConcept& g) {}
marci@651:       EdgeMap(const GraphConcept& g, T t) {}
marci@325:     
marci@325:       void set(Edge i, T t) {}
marci@325:       T get(Edge i) const {return *(T*)0;}
marci@325:       T &operator[](Edge i) {return *(T*)0;}
marci@325:     
marci@651:       void update() { }
marci@651:       //void update(T a) { }   //FIXME: Is it necessary
marci@325:     };
marci@325:   };
marci@325: 
marci@651: 
marci@651:   /// \brief Node-iterable graph concept.
marci@325:   ///
marci@651:   /// A graph class which provides functions to 
marci@651:   /// iterate on its nodes.
marci@651:   class NodeIterableGraphConcept : virtual public GraphConcept
marci@334:   {
marci@334:   public:
marci@334: 
marci@651:     /// \brief This iterator goes trough the nodes of the graph.
marci@651:     ///
marci@651:     /// This iterator goes trough the \e nodes of the graph.
marci@651:     /// Its usage is quite simple, for example you can count the number
marci@651:     /// of nodes in graph \c g of type \c Graph as follows.
marci@651:     /// \code
marci@651:     /// int count=0;
marci@651:     /// for(Graph::NodeIt n(g); g.valid(n); g.next(n)) ++count;
marci@651:     /// \endcode
marci@651:     class NodeIt : public Node {
marci@651:     public:
marci@651:       /// @warning The default constructor sets the iterator.
marci@651:       /// to an undefined value.
marci@651:       NodeIt() { }
marci@651:       // /// Copy constructor
marci@651:       //NodeIt(const NodeIt& n) { }
marci@651:       /// Initialize the iterator to be invalid.
marci@651:       NodeIt(const Invalid&) { }
marci@651:       /// \brief This constructor sets the iterator to first node.
marci@651:       ///
marci@651:       /// This constructor set the iterator to the first 
marci@651:       /// node of the graph \c g.
marci@651:       ///
marci@651:       ///@param g the graph
marci@651:       NodeIt(const GraphConcept& g) { }
marci@651:     };
marci@334: 
marci@651:     /// The first node.
marci@651:     NodeIt &first(NodeIt &i) const { return i; }
marci@651: 
marci@651:     /// Go to the next node.
marci@651:     NodeIt &next(NodeIt &i) const { return i; }
marci@651:   };
marci@651: 
marci@651: 
marci@651:   /// \brief Edge-iterable graph concept.
marci@651:   ///
marci@651:   /// A graph class which provides functions to 
marci@651:   /// iterate on its edges.
marci@651:   class EdgeIterableGraphConcept : virtual public GraphConcept
marci@651:   {
marci@651:   public:
marci@651: 
marci@651:     /// \brief This iterator goes trough the edges of the graph.
marci@651:     ///
marci@651:     /// This iterator goes trough the \e edges of the graph.
marci@651:     /// Its usage is quite simple, for example you can count the number
marci@651:     /// of edges in graph \c g of type \c Graph as follows.
marci@651:     /// \code
marci@651:     /// int count=0;
marci@651:     /// for(Graph::EdgeIt e(g); g.valid(e); g.next(e)) ++count;
marci@651:     /// \endcode
marci@651:     class EdgeIt : public Edge {
marci@651:     public:
marci@651:       /// @warning The default constructor sets the iterator.
marci@651:       /// to an undefined value.
marci@651:       EdgeIt() { }
marci@651:       // /// Copy constructor
marci@651:       // EdgeIt(const EdgeIt&) { }
marci@651:       /// Initialize the iterator to be invalid.
marci@651:       EdgeIt(const Invalid&) { }
marci@651:       /// \brief This constructor sets the iterator to first edge.
marci@651:       ///
marci@651:       /// This constructor set the iterator to the first 
marci@651:       /// edge of the graph \c g.
marci@651:       ///
marci@651:       ///@param g the graph
marci@651:       EdgeIt(const GraphConcept& g) { }
marci@651:     };
marci@651: 
marci@651:     /// The first edge.
marci@651:     EdgeIt &first(EdgeIt &i) const { return i; }
marci@651: 
marci@651:     /// Go to the next edge.
marci@651:     EdgeIt &next(EdgeIt &i) const { return i; }
marci@651:   };
marci@651: 
marci@651: 
marci@651:   /// \brief Out-edge-iterable graph concept.
marci@651:   ///
marci@651:   /// A graph class which provides functions to 
marci@651:   /// iterate on out-edges of any node.
marci@651:   class OutEdgeIterableGraphConcept : virtual public GraphConcept
marci@651:   {
marci@651:   public:
marci@651: 
marci@651:     /// \brief This iterator goes trough the outgoing edges of a node.
marci@651:     ///
marci@334:     /// This iterator goes trough the \e outgoing edges of a certain node
marci@334:     /// of a graph.
marci@334:     /// Its usage is quite simple, for example you can count the number
marci@334:     /// of outgoing edges of a node \c n
marci@651:     /// in graph \c g of type \c Graph as follows.
marci@334:     /// \code
marci@651:     /// int count=0;
marci@651:     /// for(Graph::OutEdgeIt e(g, n); g.valid(e); g.next(e)) ++count;
marci@334:     /// \endcode
marci@334:     class OutEdgeIt : public Edge {
marci@334:     public:
marci@651:       /// @warning The default constructor sets the iterator.
marci@334:       /// to an undefined value.
marci@651:       OutEdgeIt() { }
marci@651:       /// Initialize the iterator to be invalid.
marci@651:       OutEdgeIt(const Invalid&) { }
marci@651:       /// \brief This constructor sets the iterator to first outgoing edge.
marci@651:       ///
marci@334:       /// This constructor set the iterator to the first outgoing edge of
marci@334:       /// node
marci@334:       ///@param n the node
marci@651:       ///@param g the graph
marci@651:       OutEdgeIt(const GraphConcept& g, const Node& n) { }
marci@334:     };
marci@651: 
marci@651:     /// The first outgoing edge.
marci@651:     OutEdgeIt &first(OutEdgeIt &i, const Node& n) const { return i; }
marci@651: 
marci@651:     /// Go to the next outgoing edge.
marci@651:     OutEdgeIt &next(OutEdgeIt &i) const { return i; }
marci@651: 
marci@651:     Node aNode(const OutEdgeIt&) const { return Node(); }
marci@651:     Node bNode(const OutEdgeIt&) const { return Node(); }
marci@334:   };
marci@334: 
marci@651: 
marci@651:   /// \brief In-edge-iterable graph concept.
marci@651:   ///
marci@651:   /// A Graph class which provides a function to 
marci@334:   /// iterate on in-edges of any node.
marci@651:   class InEdgeIterableGraphConcept : virtual public GraphConcept
marci@334:   {
marci@334:   public:
marci@334: 
marci@651:     /// \brief This iterator goes trough the incoming edges of a node.
marci@651:     /// 
marci@334:     /// This iterator goes trough the \e incoming edges of a certain node
marci@334:     /// of a graph.
marci@334:     /// Its usage is quite simple, for example you can count the number
marci@334:     /// of incoming edges of a node \c n
marci@651:     /// in graph \c g of type \c Graph as follows.
marci@334:     /// \code
marci@651:     /// int count=0;
marci@651:     /// for(Graph::InEdgeIt e(g, n); g.valid(e); g.next(e)) ++count;
marci@334:     /// \endcode
marci@334:     class InEdgeIt : public Edge {
marci@334:     public:
marci@334:       /// @warning The default constructor sets the iterator
marci@334:       /// to an undefined value.
marci@651:       InEdgeIt() { }
marci@334:       /// Initialize the iterator to be invalid
marci@651:       InEdgeIt(const Invalid&) { }
marci@651:       /// \brief This constructor sets the iterator to first incomig edge.
marci@651:       /// 
marci@334:       /// This constructor set the iterator to the first incomig edge of
marci@334:       /// node
marci@334:       ///@param n the node
marci@651:       ///@param g the graph
marci@651:       InEdgeIt(const GraphConcept& g, const Node& n) { }
marci@334:     };
marci@651: 
marci@651:     /// The first incoming edge.
marci@651:     InEdgeIt &first(InEdgeIt &i, const Node& n) const { return i; }
marci@651: 
marci@651:     /// Go to the next incoming edge.
marci@651:     InEdgeIt &next(InEdgeIt &i) const { return i; }
marci@651: 
marci@651:     Node aNode(const InEdgeIt&) const { return Node(); }
marci@651:     Node bNode(const InEdgeIt&) const { return Node(); }
marci@334:   };
marci@334: 
marci@334: 
alpar@826:   /// \brief Node-erasable graph concept.
marci@651:   ///
marci@651:   /// A graph class which provides a function to 
marci@333:   /// delete any of its nodes.
alpar@826:   class NodeErasableGraphConcept : virtual public GraphConcept
marci@333:   {
marci@333:   public:
marci@333:     /// Deletes a node.
marci@651:     void erase(const Node& n) { }
marci@333:   };
marci@333: 
marci@651: 
alpar@826:   /// \brief Edge-erasable graph concept.
marci@651:   /// 
marci@651:   /// A graph class which provides a function to delete any 
marci@333:   /// of its edges.
alpar@826:   class EdgeErasableGraphConcept : virtual public GraphConcept
marci@333:   {
marci@333:   public:
marci@333:     /// Deletes a node.
marci@651:     void erase(const Edge& n) { }
marci@333:   };
marci@333: 
marci@651: 
marci@651:   /// \brief An empty graph class which provides a function to 
marci@651:   /// get the number of its nodes.
marci@651:   /// 
marci@325:   /// This graph class provides a function for getting the number of its 
marci@325:   /// nodes. 
marci@325:   /// Clearly, for physical graph structures it can be expected to have such a 
marci@325:   /// function. For wrappers or graphs which are given in an implicit way, 
marci@325:   /// the implementation can be circumstantial, that is why this composes a 
marci@325:   /// separate concept.
marci@651:   class NodeCountingGraphConcept : virtual public GraphConcept
marci@325:   {
marci@325:   public:
marci@325:     /// Returns the number of nodes.
marci@651:     int nodeNum() const { return 0; }
marci@325:   };
marci@325: 
marci@651: 
marci@651:   /// \brief An empty graph class which provides a function to 
marci@651:   /// get the number of its edges.
marci@651:   /// 
marci@325:   /// This graph class provides a function for getting the number of its 
marci@325:   /// edges. 
marci@325:   /// Clearly, for physical graph structures it can be expected to have such a 
marci@325:   /// function. For wrappers or graphs which are given in an implicit way, 
marci@325:   /// the implementation can be circumstantial, that is why this composes a 
marci@325:   /// separate concept.
marci@651:   class EdgeCountingGraphConcept : virtual public GraphConcept
marci@325:   {
marci@325:   public:
marci@325:     /// Returns the number of edges.
marci@651:     int edgeNum() const { return 0; }
marci@651:   };
marci@651: 
marci@652:   class FullFeatureGraphConcept : virtual public NodeIterableGraphConcept,
marci@652: 				  virtual public EdgeIterableGraphConcept, 
marci@652: 				  virtual public OutEdgeIterableGraphConcept, 
marci@652: 				  virtual public InEdgeIterableGraphConcept, 
marci@652: 				  virtual public NodeCountingGraphConcept {
marci@651:   public:
marci@651:     FullFeatureGraphConcept() { }
marci@652:     using EdgeIterableGraphConcept::next;
marci@652:     using NodeIterableGraphConcept::next;
marci@652:     using OutEdgeIterableGraphConcept::next;    
marci@652:     using InEdgeIterableGraphConcept::next;
marci@325:   };
marci@332:   
marci@332:   /// @}
marci@325: 
alpar@921: } //namespace lemon
marci@325: 
marci@325: 
marci@332: 
marci@651: // class EmptyBipGraph : public Graph Concept
marci@325: // {
marci@325: //   class ANode {};
marci@325: //   class BNode {};
marci@325: 
marci@325: //   ANode &next(ANode &) {}
marci@325: //   BNode &next(BNode &) {}
marci@325: 
marci@325: //   ANode &getFirst(ANode &) const {}
marci@325: //   BNode &getFirst(BNode &) const {}
marci@325: 
marci@325: //   enum NodeClass { A = 0, B = 1 };
marci@325: //   NodeClass getClass(Node n) {}
marci@325: 
marci@325: // }
marci@325: 
alpar@921: #endif // LEMON_GRAPH_H