marci@174: // -*- c++ -*-
marci@174: #ifndef EMPTYGRAPH_H
marci@174: #define EMPTYGRAPH_H
alpar@52: 
alpar@163: #include <invalid.h>
alpar@145: 
alpar@163: /// The namespace of HugoLib
alpar@163: namespace hugo {
alpar@163: 
alpar@163:   // @defgroup empty_graph The EmptyGraph class
alpar@163:   // @{
alpar@163: 
alpar@163:   /// An empty graph class.
alpar@163:   
alpar@163:   /// This class provides all the common features of a grapf structure,
alpar@163:   /// however completely without implementations or real data structures
alpar@163:   /// behind the interface.
alpar@163:   /// All graph algorithms should compile with this class, but it will not
alpar@163:   /// run properly, of course.
alpar@163:   ///
alpar@163:   /// It can be used for checking the interface compatibility,
alpar@163:   /// or it can serve as a skeleton of a new graph structure.
alpar@165:   /// 
alpar@165:   /// Also, you will find here the full documentation of a certain graph
alpar@165:   /// feature, the documentation of a real graph imlementation
alpar@165:   /// like @ref ListGraph or
alpar@165:   /// @ref SmartGraph will just refer to this structure.
alpar@163:   class EmptyGraph
alpar@163:   {
alpar@147:   public:
alpar@147:     
alpar@163:     /// The base type of the node iterators.
alpar@163:     class Node {
alpar@163:     public:
alpar@163:       /// @warning The default constructor sets the iterator
alpar@163:       /// to an undefined value.
alpar@163:       Node() {}   //FIXME
alpar@163:       /// Initialize the iterator to be invalid
marci@174:       Node(Invalid) {}
alpar@163:       //Node(const Node &) {} 
alpar@163:       bool operator==(Node n) const { return true; } //FIXME
alpar@163:       bool operator!=(Node n) const { return true; } //FIXME
alpar@163:     };
alpar@147:     
alpar@163:     /// This iterator goes through each node.
alpar@163:     class NodeIt : public Node {
alpar@163:     public:
alpar@163:       /// @warning The default constructor sets the iterator
alpar@163:       /// to an undefined value.
alpar@163:       NodeIt() {} //FIXME
alpar@163:       /// Initialize the iterator to be invalid
marci@174:       NodeIt(Invalid) {}
alpar@163:       /// Sets the iterator to the first node of \c G.
alpar@163:       NodeIt(const EmptyGraph &G) {}
alpar@163:       NodeIt(const NodeIt &) {} //FIXME
alpar@163:     };
alpar@163:     
alpar@163:     
alpar@163:     /// The base type of the edge iterators.
alpar@163:     class Edge {
alpar@163:     public:
alpar@163:       /// @warning The default constructor sets the iterator
alpar@163:       /// to an undefined value.
alpar@163:       Edge() {}   //FIXME
alpar@163:       /// Initialize the iterator to be invalid
marci@174:       Edge(Invalid) {}
alpar@163:       //Edge(const Edge &) {} 
alpar@163:       bool operator==(Edge n) const { return true; } //FIXME
alpar@163:       bool operator!=(Edge n) const { return true; } //FIXME    
alpar@163:     };
alpar@163:     
alpar@163:     /// This iterator goes trought the outgoing edges of a certain graph.
alpar@163:     
alpar@163:     class OutEdgeIt : public Edge {
alpar@163:     public:
alpar@163:       /// @warning The default constructor sets the iterator
alpar@163:       /// to an undefined value.
alpar@163:       OutEdgeIt() {}
alpar@163:       /// Initialize the iterator to be invalid
marci@174:       OutEdgeIt(Invalid) {}
alpar@163:       /// This constructor sets the iterator to first outgoing edge.
alpar@163:     
alpar@163:       /// This constructor set the iterator to the first outgoing edge of
alpar@163:       /// node
alpar@163:       ///@param n the node
alpar@163:       ///@param G the graph
alpar@163:       OutEdgeIt(const EmptyGraph & G, Node n) {}
alpar@163:     };
alpar@163: 
alpar@163:     class InEdgeIt : public Edge {
alpar@163:     public:
alpar@163:       /// @warning The default constructor sets the iterator
alpar@163:       /// to an undefined value.
alpar@163:       InEdgeIt() {}
alpar@163:       /// Initialize the iterator to be invalid
marci@174:       InEdgeIt(Invalid) {}
alpar@163:       InEdgeIt(const EmptyGraph &, Node) {}    
alpar@163:     };
alpar@163:     //  class SymEdgeIt : public Edge {};
alpar@163:     class EdgeIt : public Edge {
alpar@163:     public:
alpar@163:       /// @warning The default constructor sets the iterator
alpar@163:       /// to an undefined value.
alpar@163:       EdgeIt() {}
alpar@163:       /// Initialize the iterator to be invalid
marci@174:       EdgeIt(Invalid) {}
alpar@163:       EdgeIt(const EmptyGraph &) {}
alpar@163:     };
alpar@163: 
alpar@163:     /// First node of the graph.
alpar@163: 
alpar@163:     /// \post \c i and the return value will be the first node.
alpar@163:     ///
alpar@163:     NodeIt &first(NodeIt &i) const { return i;}
alpar@163: 
alpar@163:     /// The first outgoing edge.
alpar@163:     InEdgeIt &first(InEdgeIt &i, Node n) const { return i;}
alpar@163:     /// The first incoming edge.
alpar@163:     OutEdgeIt &first(OutEdgeIt &i, Node n) const { return i;}
alpar@163:     //  SymEdgeIt &first(SymEdgeIt &, Node) const { return i;}
alpar@163:     /// The first edge of the Graph.
alpar@163:     EdgeIt &first(EdgeIt &i) const { return i;}
alpar@163: 
alpar@163: //     Node getNext(Node) const {}
alpar@163: //     InEdgeIt getNext(InEdgeIt) const {}
alpar@163: //     OutEdgeIt getNext(OutEdgeIt) const {}
alpar@163: //     //SymEdgeIt getNext(SymEdgeIt) const {}
alpar@163: //     EdgeIt getNext(EdgeIt) const {}
alpar@163: 
alpar@163:     /// Go to the next node.
marci@178:     NodeIt &next(NodeIt &i) const { return i;}
alpar@163:     /// Go to the next incoming edge.
alpar@163:     InEdgeIt &next(InEdgeIt &i) const { return i;}
alpar@163:     /// Go to the next outgoing edge.
alpar@163:     OutEdgeIt &next(OutEdgeIt &i) const { return i;}
alpar@163:     //SymEdgeIt &next(SymEdgeIt &) const {}
alpar@163:     /// Go to the next edge.
alpar@163:     EdgeIt &next(EdgeIt &i) const { return i;}
alpar@163: 
alpar@163:     ///Gives back the head node of an edge.
alpar@163:     Node head(Edge) const { return INVALID; }
alpar@163:     ///Gives back the tail node of an edge.
alpar@163:     Node tail(Edge) const { return INVALID; }
alpar@52:   
alpar@163:     //   Node aNode(InEdgeIt) const {}
alpar@163:     //   Node aNode(OutEdgeIt) const {}
alpar@163:     //   Node aNode(SymEdgeIt) const {}
alpar@163: 
alpar@163:     //   Node bNode(InEdgeIt) const {}
alpar@163:     //   Node bNode(OutEdgeIt) const {}
alpar@163:     //   Node bNode(SymEdgeIt) const {}
alpar@163: 
alpar@163:     /// Checks if a node iterator is valid
marci@174:     bool valid(const Node) const { return true;}
alpar@163:     /// Checks if an edge iterator is valid
marci@174:     bool valid(const Edge) const { return true;}
alpar@163: 
alpar@163:     ///Gives back the \e id of a node.
marci@174:     int id(const Node) const { return 0;}
alpar@163:     ///Gives back the \e id of an edge.
marci@174:     int id(const Edge) const { return 0;}
alpar@163: 
alpar@163:     //void setInvalid(Node &) const {};
alpar@163:     //void setInvalid(Edge &) const {};
alpar@163:   
alpar@163:     Node addNode() { return INVALID;}
alpar@163:     Edge addEdge(Node tail, Node head) { return INVALID;}
alpar@163:     
alpar@163:     void erase(Node n) {}
alpar@163:     void erase(Edge e) {}
alpar@163: 
alpar@163:     void clear() {}
alpar@163: 
alpar@163:     int nodeNum() { return 0;}
alpar@163:     int edgeNum() { return 0;}
alpar@163: 
marci@174:     EmptyGraph() {}
marci@174:     EmptyGraph(const EmptyGraph &G) {}
alpar@163:   
alpar@163:   
alpar@163: 
alpar@163:     ///Read/write map from the nodes to type \c T.
alpar@163:     template<class T> class NodeMap
alpar@163:     {
alpar@163:     public:
alpar@163:       typedef T ValueType;
alpar@163:       typedef Node KeyType;
alpar@163: 
alpar@163:       NodeMap(const EmptyGraph &G) {}
alpar@163:       NodeMap(const EmptyGraph &G, T t) {}
alpar@163: 
alpar@163:       void set(Node i, T t) {}
alpar@163:       T get(Node i) const {return *(T*)NULL;}  //FIXME: Is it necessary
alpar@163:       T &operator[](Node i) {return *(T*)NULL;}
alpar@163:       const T &operator[](Node i) const {return *(T*)NULL;}
alpar@163: 
alpar@163:       void update() {}
alpar@163:       void update(T a) {}   //FIXME: Is it necessary
alpar@163:     };
alpar@163: 
alpar@163:     ///Read/write map from the edges to type \c T.
alpar@163:     template<class T> class EdgeMap
alpar@163:     {
alpar@163:     public:
alpar@163:       typedef T ValueType;
alpar@163:       typedef Edge KeyType;
alpar@163: 
alpar@163:       EdgeMap(const EmptyGraph &G) {}
alpar@163:       EdgeMap(const EmptyGraph &G, T t) {}
alpar@163:     
alpar@163:       void set(Edge i, T t) {}
alpar@163:       T get(Edge i) const {return *(T*)NULL;}
alpar@163:       T &operator[](Edge i) {return *(T*)NULL;}
alpar@163:     
alpar@163:       void update() {}
alpar@163:       void update(T a) {}   //FIXME: Is it necessary
alpar@163:     };
alpar@147:   };
alpar@52: 
alpar@163:   // @}
alpar@147: 
marci@174: } //namespace hugo
alpar@52: 
alpar@145: 
alpar@145: 
alpar@147: // class EmptyBipGraph : public EmptyGraph
alpar@147: // {
alpar@163: //   class ANode {};
alpar@163: //   class BNode {};
alpar@145: 
alpar@163: //   ANode &next(ANode &) {}
alpar@163: //   BNode &next(BNode &) {}
alpar@145: 
alpar@163: //   ANode &getFirst(ANode &) const {}
alpar@163: //   BNode &getFirst(BNode &) const {}
alpar@145: 
alpar@147: //   enum NodeClass { A = 0, B = 1 };
alpar@163: //   NodeClass getClass(Node n) {}
alpar@147: 
alpar@147: // }
marci@174: 
marci@174: #endif // EMPTYGRAPH_H