deba@1791: /* -*- C++ -*-
deba@1791:  * lemon/graph_extender.h - Part of LEMON, a generic C++ optimization library
deba@1791:  *
deba@1791:  * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi
deba@1791:  * Kutatocsoport (Egervary Research Group on Combinatorial Optimization,
deba@1791:  * EGRES).
deba@1791:  *
deba@1791:  * Permission to use, modify and distribute this software is granted
deba@1791:  * provided that this copyright notice appears in all copies. For
deba@1791:  * precise terms see the accompanying LICENSE file.
deba@1791:  *
deba@1791:  * This software is provided "AS IS" with no warranty of any kind,
deba@1791:  * express or implied, and with no claim as to its suitability for any
deba@1791:  * purpose.
deba@1791:  *
deba@1791:  */
deba@1791: 
deba@1791: #ifndef LEMON_GRAPH_EXTENDER_H
deba@1791: #define LEMON_GRAPH_EXTENDER_H
deba@1791: 
deba@1791: #include <lemon/invalid.h>
deba@1791: 
deba@1791: namespace lemon {
deba@1791: 
deba@1791:   template <typename _Base>
deba@1791:   class GraphExtender : public _Base {
deba@1791:   public:
deba@1791: 
deba@1791:     typedef _Base Parent;
deba@1791:     typedef GraphExtender Graph;
deba@1791: 
deba@1791:     typedef typename Parent::Node Node;
deba@1791:     typedef typename Parent::Edge Edge;
deba@1791: 
deba@1791:     int maxId(Node) const {
deba@1791:       return Parent::maxNodeId();
deba@1791:     }
deba@1791: 
deba@1791:     int maxId(Edge) const {
deba@1791:       return Parent::maxEdgeId();
deba@1791:     }
deba@1791: 
deba@1791:     Node fromId(int id, Node) const {
deba@1791:       return Parent::nodeFromId(id);
deba@1791:     }
deba@1791: 
deba@1791:     Edge fromId(int id, Edge) const {
deba@1791:       return Parent::edgeFromId(id);
deba@1791:     }
deba@1791: 
deba@1791:     Node oppositeNode(const Node &n, const Edge &e) const {
deba@1791:       if (n == Parent::source(e))
deba@1791: 	return Parent::target(e);
deba@1791:       else if(n==Parent::target(e))
deba@1791: 	return Parent::source(e);
deba@1791:       else
deba@1791: 	return INVALID;
deba@1791:     }
deba@1791: 
deba@1791:   };
deba@1791: 
deba@1791:   template <typename _Base>
deba@1791:   class UndirGraphExtender : public _Base {
deba@1791:     typedef _Base Parent;
deba@1791:     typedef UndirGraphExtender Graph;
deba@1791: 
deba@1791:   public:
deba@1791: 
deba@1791:     typedef typename Parent::Edge UndirEdge;
deba@1791:     typedef typename Parent::Node Node;
deba@1791: 
deba@1791:     class Edge : public UndirEdge {
deba@1791:       friend class UndirGraphExtender;
deba@1791: 
deba@1791:     protected:
deba@1791:       // FIXME: Marci use opposite logic in his graph adaptors. It would
deba@1791:       // be reasonable to syncronize...
deba@1791:       bool forward;
deba@1791: 
deba@1791:       Edge(const UndirEdge &ue, bool _forward) :
deba@1791:         UndirEdge(ue), forward(_forward) {}
deba@1791: 
deba@1791:     public:
deba@1791:       Edge() {}
deba@1791: 
deba@1791:       /// Invalid edge constructor
deba@1791:       Edge(Invalid i) : UndirEdge(i), forward(true) {}
deba@1791: 
deba@1791:       bool operator==(const Edge &that) const {
deba@1791: 	return forward==that.forward && UndirEdge(*this)==UndirEdge(that);
deba@1791:       }
deba@1791:       bool operator!=(const Edge &that) const {
deba@1791: 	return forward!=that.forward || UndirEdge(*this)!=UndirEdge(that);
deba@1791:       }
deba@1791:       bool operator<(const Edge &that) const {
deba@1791: 	return forward<that.forward ||
deba@1791: 	  (!(that.forward<forward) && UndirEdge(*this)<UndirEdge(that));
deba@1791:       }
deba@1791:     };
deba@1791: 
deba@1791: 
deba@1791:     /// \brief Edge of opposite direction.
deba@1791:     ///
deba@1791:     /// Returns the Edge of opposite direction.
deba@1791:     Edge oppositeEdge(const Edge &e) const {
deba@1791:       return Edge(e,!e.forward);
deba@1791:     }
deba@1791: 
deba@1791:   public:
deba@1791:     /// \todo Shouldn't the "source" of an undirected edge be called "aNode"
deba@1791:     /// or something???
deba@1791:     using Parent::source;
deba@1791: 
deba@1791:     /// Source of the given Edge.
deba@1791:     Node source(const Edge &e) const {
deba@1791:       return e.forward ? Parent::source(e) : Parent::target(e);
deba@1791:     }
deba@1791: 
deba@1791:     /// \todo Shouldn't the "target" of an undirected edge be called "bNode"
deba@1791:     /// or something???
deba@1791:     using Parent::target;
deba@1791: 
deba@1791:     /// Target of the given Edge.
deba@1791:     Node target(const Edge &e) const {
deba@1791:       return e.forward ? Parent::target(e) : Parent::source(e);
deba@1791:     }
deba@1791: 
deba@1791:     Node oppositeNode(const Node &n, const UndirEdge &e) const {
deba@1791:       if( n == Parent::source(e))
deba@1791: 	return Parent::target(e);
deba@1791:       else if( n == Parent::target(e))
deba@1791: 	return Parent::source(e);
deba@1791:       else
deba@1791: 	return INVALID;
deba@1791:     }
deba@1791: 
deba@1791:     /// \brief Directed edge from an undirected edge and a source node.
deba@1791:     ///
deba@1791:     /// Returns a (directed) Edge corresponding to the specified UndirEdge
deba@1791:     /// and source Node.
deba@1791:     ///
deba@1791:     Edge direct(const UndirEdge &ue, const Node &s) const {
deba@1791:       return Edge(ue, s == source(ue));
deba@1791:     }
deba@1791: 
deba@1791:     /// \brief Directed edge from an undirected edge.
deba@1791:     ///
deba@1791:     /// Returns a directed edge corresponding to the specified UndirEdge.
deba@1791:     /// If the given bool is true the given undirected edge and the
deba@1791:     /// returned edge have the same source node.
deba@1791:     Edge direct(const UndirEdge &ue, bool d) const {
deba@1791:       return Edge(ue, d);
deba@1791:     }
deba@1791: 
deba@1791:     /// Returns whether the given directed edge is same orientation as the
deba@1791:     /// corresponding undirected edge.
deba@1791:     ///
deba@1791:     /// \todo reference to the corresponding point of the undirected graph
deba@1791:     /// concept. "What does the direction of an undirected edge mean?"
deba@1791:     bool direction(const Edge &e) const { return e.forward; }
deba@1791: 
deba@1791: 
deba@1791:     using Parent::first;
deba@1791:     void first(Edge &e) const {
deba@1791:       Parent::first(e);
deba@1791:       e.forward=true;
deba@1791:     }
deba@1791: 
deba@1791:     using Parent::next;
deba@1791:     void next(Edge &e) const {
deba@1791:       if( e.forward ) {
deba@1791: 	e.forward = false;
deba@1791:       }
deba@1791:       else {
deba@1791: 	Parent::next(e);
deba@1791: 	e.forward = true;
deba@1791:       }
deba@1791:     }
deba@1791: 
deba@1791:   public:
deba@1791: 
deba@1791:     void firstOut(Edge &e, const Node &n) const {
deba@1791:       Parent::firstIn(e,n);
deba@1791:       if( UndirEdge(e) != INVALID ) {
deba@1791: 	e.forward = false;
deba@1791:       }
deba@1791:       else {
deba@1791: 	Parent::firstOut(e,n);
deba@1791: 	e.forward = true;
deba@1791:       }
deba@1791:     }
deba@1791:     void nextOut(Edge &e) const {
deba@1791:       if( ! e.forward ) {
deba@1791: 	Node n = Parent::target(e);
deba@1791: 	Parent::nextIn(e);
deba@1791: 	if( UndirEdge(e) == INVALID ) {
deba@1791: 	  Parent::firstOut(e, n);
deba@1791: 	  e.forward = true;
deba@1791: 	}
deba@1791:       }
deba@1791:       else {
deba@1791: 	Parent::nextOut(e);
deba@1791:       }
deba@1791:     }
deba@1791: 
deba@1791:     void firstIn(Edge &e, const Node &n) const {
deba@1791:       Parent::firstOut(e,n);
deba@1791:       if( UndirEdge(e) != INVALID ) {
deba@1791: 	e.forward = false;
deba@1791:       }
deba@1791:       else {
deba@1791: 	Parent::firstIn(e,n);
deba@1791: 	e.forward = true;
deba@1791:       }
deba@1791:     }
deba@1791:     void nextIn(Edge &e) const {
deba@1791:       if( ! e.forward ) {
deba@1791: 	Node n = Parent::source(e);
deba@1791: 	Parent::nextOut(e);
deba@1791: 	if( UndirEdge(e) == INVALID ) {
deba@1791: 	  Parent::firstIn(e, n);
deba@1791: 	  e.forward = true;
deba@1791: 	}
deba@1791:       }
deba@1791:       else {
deba@1791: 	Parent::nextIn(e);
deba@1791:       }
deba@1791:     }
deba@1791: 
deba@1791:     void firstInc(UndirEdge &e, const Node &n) const {
deba@1791:       Parent::firstOut(e, n);
deba@1791:       if (e != INVALID) return;
deba@1791:       Parent::firstIn(e, n);
deba@1791:     }
deba@1791:     void nextInc(UndirEdge &e, const Node &n) const {
deba@1791:       if (Parent::source(e) == n) {
deba@1791: 	Parent::nextOut(e);
deba@1791: 	if (e != INVALID) return;
deba@1791: 	Parent::firstIn(e, n);
deba@1791:       } else {
deba@1791: 	Parent::nextIn(e);
deba@1791:       }
deba@1791:     }
deba@1791: 
deba@1791:     void firstInc(UndirEdge &e, bool &d, const Node &n) const {
deba@1791:       d = true;
deba@1791:       Parent::firstOut(e, n);
deba@1791:       if (e != INVALID) return;
deba@1791:       d = false;
deba@1791:       Parent::firstIn(e, n);
deba@1791:     }
deba@1791:     void nextInc(UndirEdge &e, bool &d) const {
deba@1791:       if (d) {
deba@1791: 	Node s = Parent::source(e);
deba@1791: 	Parent::nextOut(e);
deba@1791: 	if (e != INVALID) return;
deba@1791: 	d = false;
deba@1791: 	Parent::firstIn(e, s);
deba@1791:       } else {
deba@1791: 	Parent::nextIn(e);
deba@1791:       }
deba@1791:     }
deba@1791: 
deba@1791:     // Miscellaneous stuff:
deba@1791: 
deba@1791:     /// \todo these methods (id, maxEdgeId) should be moved into separate
deba@1791:     /// Extender
deba@1791: 
deba@1791:     // using Parent::id;
deba@1791:     // Using "using" is not a good idea, cause it could be that there is
deba@1791:     // no "id" in Parent...
deba@1791: 
deba@1791:     int id(const Node &n) const {
deba@1791:       return Parent::id(n);
deba@1791:     }
deba@1791: 
deba@1791:     int id(const UndirEdge &e) const {
deba@1791:       return Parent::id(e);
deba@1791:     }
deba@1791: 
deba@1791:     int id(const Edge &e) const {
deba@1791:       return 2 * Parent::id(e) + int(e.forward);
deba@1791:     }
deba@1791: 
deba@1791:     int maxNodeId() const {
deba@1791:       return Parent::maxNodeId();
deba@1791:     }
deba@1791: 
deba@1791:     int maxEdgeId() const {
deba@1791:       return 2 * Parent::maxEdgeId() + 1;
deba@1791:     }
deba@1791: 
deba@1791:     int maxUndirEdgeId() const {
deba@1791:       return Parent::maxEdgeId();
deba@1791:     }
deba@1791: 
deba@1791:     int maxId(Node) const {
deba@1791:       return maxNodeId();
deba@1791:     }
deba@1791: 
deba@1791:     int maxId(Edge) const {
deba@1791:       return maxEdgeId();
deba@1791:     }
deba@1791:     int maxId(UndirEdge) const {
deba@1791:       return maxUndirEdgeId();
deba@1791:     }
deba@1791: 
deba@1791:     int edgeNum() const {
deba@1791:       return 2 * Parent::edgeNum();
deba@1791:     }
deba@1791: 
deba@1791:     int undirEdgeNum() const {
deba@1791:       return Parent::edgeNum();
deba@1791:     }
deba@1791: 
deba@1791:     Node nodeFromId(int id) const {
deba@1791:       return Parent::nodeFromId(id);
deba@1791:     }
deba@1791: 
deba@1791:     Edge edgeFromId(int id) const {
deba@1791:       return direct(Parent::edgeFromId(id >> 1), bool(id & 1));
deba@1791:     }
deba@1791: 
deba@1791:     UndirEdge undirEdgeFromId(int id) const {
deba@1791:       return Parent::edgeFromId(id >> 1);
deba@1791:     }
deba@1791: 
deba@1791:     Node fromId(int id, Node) const {
deba@1791:       return nodeFromId(id);
deba@1791:     }
deba@1791: 
deba@1791:     Edge fromId(int id, Edge) const {
deba@1791:       return edgeFromId(id);
deba@1791:     }
deba@1791: 
deba@1791:     UndirEdge fromId(int id, UndirEdge) const {
deba@1791:       return undirEdgeFromId(id);
deba@1791:     }
deba@1791: 
deba@1791: 
deba@1791:     Edge findEdge(Node source, Node target, Edge prev) const {
deba@1791:       if (prev == INVALID) {
deba@1791: 	UndirEdge edge = Parent::findEdge(source, target);
deba@1791: 	if (edge != INVALID) return direct(edge, true);
deba@1791: 	edge = Parent::findEdge(target, source);
deba@1791: 	if (edge != INVALID) return direct(edge, false);
deba@1791:       } else if (direction(prev)) {
deba@1791: 	UndirEdge edge = Parent::findEdge(source, target, prev);
deba@1791: 	if (edge != INVALID) return direct(edge, true);
deba@1791: 	edge = Parent::findEdge(target, source);
deba@1791: 	if (edge != INVALID) return direct(edge, false);	
deba@1791:       } else {
deba@1791: 	UndirEdge edge = Parent::findEdge(target, source, prev);
deba@1791: 	if (edge != INVALID) return direct(edge, false);	      
deba@1791:       }
deba@1791:       return INVALID;
deba@1791:     }
deba@1791: 
deba@1791:     UndirEdge findUndirEdge(Node source, Node target, UndirEdge prev) const {
deba@1791:       if (prev == INVALID) {
deba@1791: 	UndirEdge edge = Parent::findEdge(source, target);
deba@1791: 	if (edge != INVALID) return edge;
deba@1791: 	edge = Parent::findEdge(target, source);
deba@1791: 	if (edge != INVALID) return edge;
deba@1791:       } else if (Parent::source(prev) == source) {
deba@1791: 	UndirEdge edge = Parent::findEdge(source, target, prev);
deba@1791: 	if (edge != INVALID) return edge;
deba@1791: 	edge = Parent::findEdge(target, source);
deba@1791: 	if (edge != INVALID) return edge;	
deba@1791:       } else {
deba@1791: 	UndirEdge edge = Parent::findEdge(target, source, prev);
deba@1791: 	if (edge != INVALID) return edge;	      
deba@1791:       }
deba@1791:       return INVALID;
deba@1791:     }
deba@1791: 
deba@1791:   };
deba@1791: 
deba@1791: }
deba@1791: 
deba@1791: #endif // LEMON_UNDIR_GRAPH_EXTENDER_H