diff -r d8475431bbbb -r 8e85e6bbefdf lemon/list_graph.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lemon/list_graph.h	Mon May 23 04:48:14 2005 +0000
@@ -0,0 +1,565 @@
+/* -*- C++ -*-
+ * lemon/list_graph.h - Part of LEMON, a generic C++ optimization library
+ *
+ * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
+ * (Egervary Research Group on Combinatorial Optimization, EGRES).
+ *
+ * Permission to use, modify and distribute this software is granted
+ * provided that this copyright notice appears in all copies. For
+ * precise terms see the accompanying LICENSE file.
+ *
+ * This software is provided "AS IS" with no warranty of any kind,
+ * express or implied, and with no claim as to its suitability for any
+ * purpose.
+ *
+ */
+
+#ifndef LEMON_LIST_GRAPH_H
+#define LEMON_LIST_GRAPH_H
+
+///\ingroup graphs
+///\file
+///\brief ListGraph, SymListGraph classes.
+
+#include <lemon/bits/erasable_graph_extender.h>
+#include <lemon/bits/clearable_graph_extender.h>
+#include <lemon/bits/extendable_graph_extender.h>
+#include <lemon/bits/iterable_graph_extender.h>
+#include <lemon/bits/alteration_notifier.h>
+#include <lemon/bits/default_map.h>
+
+#include <lemon/bits/undir_graph_extender.h>
+
+#include <list>
+
+namespace lemon {
+
+  class ListGraphBase {
+
+  protected:
+    struct NodeT {
+      int first_in,first_out;
+      int prev, next;
+    };
+ 
+    struct EdgeT {
+      int target, source;
+      int prev_in, prev_out;
+      int next_in, next_out;
+    };
+
+    std::vector<NodeT> nodes;
+
+    int first_node;
+
+    int first_free_node;
+
+    std::vector<EdgeT> edges;
+
+    int first_free_edge;
+    
+  public:
+    
+    typedef ListGraphBase Graph;
+    
+    class Node {
+      friend class ListGraphBase;
+    protected:
+
+      int id;
+      Node(int pid) { id = pid;}
+
+    public:
+      Node() {}
+      Node (Invalid) { id = -1; }
+      bool operator==(const Node& node) const {return id == node.id;}
+      bool operator!=(const Node& node) const {return id != node.id;}
+      bool operator<(const Node& node) const {return id < node.id;}
+    };
+
+    class Edge {
+      friend class ListGraphBase;
+    protected:
+
+      int id;
+      Edge(int pid) { id = pid;}
+
+    public:
+      Edge() {}
+      Edge (Invalid) { id = -1; }
+      bool operator==(const Edge& edge) const {return id == edge.id;}
+      bool operator!=(const Edge& edge) const {return id != edge.id;}
+      bool operator<(const Edge& edge) const {return id < edge.id;}
+    };
+
+
+
+    ListGraphBase()
+      : nodes(), first_node(-1),
+	first_free_node(-1), edges(), first_free_edge(-1) {}
+
+    
+    /// Maximum node ID.
+    
+    /// Maximum node ID.
+    ///\sa id(Node)
+    int maxId(Node = INVALID) const { return nodes.size()-1; } 
+
+    /// Maximum edge ID.
+    
+    /// Maximum edge ID.
+    ///\sa id(Edge)
+    int maxId(Edge = INVALID) const { return edges.size()-1; }
+
+    Node source(Edge e) const { return edges[e.id].source; }
+    Node target(Edge e) const { return edges[e.id].target; }
+
+
+    void first(Node& node) const { 
+      node.id = first_node;
+    }
+
+    void next(Node& node) const {
+      node.id = nodes[node.id].next;
+    }
+
+
+    void first(Edge& e) const { 
+      int n;
+      for(n = first_node; 
+	  n!=-1 && nodes[n].first_in == -1; 
+	  n = nodes[n].next);
+      e.id = (n == -1) ? -1 : nodes[n].first_in;
+    }
+
+    void next(Edge& edge) const {
+      if (edges[edge.id].next_in != -1) {
+	edge.id = edges[edge.id].next_in;
+      } else {
+	int n;
+	for(n = nodes[edges[edge.id].target].next;
+	  n!=-1 && nodes[n].first_in == -1; 
+	  n = nodes[n].next);
+	edge.id = (n == -1) ? -1 : nodes[n].first_in;
+      }      
+    }
+
+    void firstOut(Edge &e, const Node& v) const {
+      e.id = nodes[v.id].first_out;
+    }
+    void nextOut(Edge &e) const {
+      e.id=edges[e.id].next_out;
+    }
+
+    void firstIn(Edge &e, const Node& v) const {
+      e.id = nodes[v.id].first_in;
+    }
+    void nextIn(Edge &e) const {
+      e.id=edges[e.id].next_in;
+    }
+
+    
+    static int id(Node v) { return v.id; }
+    static int id(Edge e) { return e.id; }
+
+    static Node fromId(int id, Node) { return Node(id);}
+    static Edge fromId(int id, Edge) { return Edge(id);}
+
+    /// Adds a new node to the graph.
+
+    /// \warning It adds the new node to the front of the list.
+    /// (i.e. the lastly added node becomes the first.)
+    Node addNode() {     
+      int n;
+      
+      if(first_free_node==-1) {
+	n = nodes.size();
+	nodes.push_back(NodeT());
+      } else {
+	n = first_free_node;
+	first_free_node = nodes[n].next;
+      }
+      
+      nodes[n].next = first_node;
+      if(first_node != -1) nodes[first_node].prev = n;
+      first_node = n;
+      nodes[n].prev = -1;
+      
+      nodes[n].first_in = nodes[n].first_out = -1;
+      
+      return Node(n);
+    }
+    
+    Edge addEdge(Node u, Node v) {
+      int n;      
+
+      if (first_free_edge == -1) {
+	n = edges.size();
+	edges.push_back(EdgeT());
+      } else {
+	n = first_free_edge;
+	first_free_edge = edges[n].next_in;
+      }
+      
+      edges[n].source = u.id; 
+      edges[n].target = v.id;
+
+      edges[n].next_out = nodes[u.id].first_out;
+      if(nodes[u.id].first_out != -1) {
+	edges[nodes[u.id].first_out].prev_out = n;
+      }
+      
+      edges[n].next_in = nodes[v.id].first_in;
+      if(nodes[v.id].first_in != -1) {
+	edges[nodes[v.id].first_in].prev_in = n;
+      }
+      
+      edges[n].prev_in = edges[n].prev_out = -1;
+	
+      nodes[u.id].first_out = nodes[v.id].first_in = n;
+
+      return Edge(n);
+    }
+    
+    void erase(const Node& node) {
+      int n = node.id;
+      
+      if(nodes[n].next != -1) {
+	nodes[nodes[n].next].prev = nodes[n].prev;
+      }
+      
+      if(nodes[n].prev != -1) {
+	nodes[nodes[n].prev].next = nodes[n].next;
+      } else {
+	first_node = nodes[n].next;
+      }
+      
+      nodes[n].next = first_free_node;
+      first_free_node = n;
+
+    }
+    
+    void erase(const Edge& edge) {
+      int n = edge.id;
+      
+      if(edges[n].next_in!=-1) {
+	edges[edges[n].next_in].prev_in = edges[n].prev_in;
+      }
+
+      if(edges[n].prev_in!=-1) {
+	edges[edges[n].prev_in].next_in = edges[n].next_in;
+      } else {
+	nodes[edges[n].target].first_in = edges[n].next_in;
+      }
+
+      
+      if(edges[n].next_out!=-1) {
+	edges[edges[n].next_out].prev_out = edges[n].prev_out;
+      } 
+
+      if(edges[n].prev_out!=-1) {
+	edges[edges[n].prev_out].next_out = edges[n].next_out;
+      } else {
+	nodes[edges[n].source].first_out = edges[n].next_out;
+      }
+      
+      edges[n].next_in = first_free_edge;
+      first_free_edge = n;      
+
+    }
+
+    void clear() {
+      edges.clear();
+      nodes.clear();
+      first_node = first_free_node = first_free_edge = -1;
+    }
+
+  protected:
+    void _moveTarget(Edge e, Node n) 
+    {
+      if(edges[e.id].next_in != -1)
+	edges[edges[e.id].next_in].prev_in = edges[e.id].prev_in;
+      if(edges[e.id].prev_in != -1)
+	edges[edges[e.id].prev_in].next_in = edges[e.id].next_in;
+      else nodes[edges[e.id].target].first_in = edges[e.id].next_in;
+      edges[e.id].target = n.id;
+      edges[e.id].prev_in = -1;
+      edges[e.id].next_in = nodes[n.id].first_in;
+      nodes[n.id].first_in = e.id;
+    }
+    void _moveSource(Edge e, Node n) 
+    {
+      if(edges[e.id].next_out != -1)
+	edges[edges[e.id].next_out].prev_out = edges[e.id].prev_out;
+      if(edges[e.id].prev_out != -1)
+	edges[edges[e.id].prev_out].next_out = edges[e.id].next_out;
+      else nodes[edges[e.id].source].first_out = edges[e.id].next_out;
+      edges[e.id].source = n.id;
+      edges[e.id].prev_out = -1;
+      edges[e.id].next_out = nodes[n.id].first_out;
+      nodes[n.id].first_out = e.id;
+    }
+
+  };
+
+  typedef AlterableGraphExtender<ListGraphBase> AlterableListGraphBase;
+  typedef IterableGraphExtender<AlterableListGraphBase> IterableListGraphBase;
+  typedef DefaultMappableGraphExtender<IterableListGraphBase> MappableListGraphBase;
+  typedef ExtendableGraphExtender<MappableListGraphBase> ExtendableListGraphBase;
+  typedef ClearableGraphExtender<ExtendableListGraphBase> ClearableListGraphBase;
+  typedef ErasableGraphExtender<ClearableListGraphBase> ErasableListGraphBase;
+
+/// \addtogroup graphs
+/// @{
+
+  ///A list graph class.
+
+  ///This is a simple and fast erasable graph implementation.
+  ///
+  ///It addition that it conforms to the
+  ///\ref concept::ErasableGraph "ErasableGraph" concept,
+  ///it also provides several additional useful extra functionalities.
+  ///\sa concept::ErasableGraph.
+
+  class ListGraph : public ErasableListGraphBase 
+  {
+  public:
+    /// Moves the target of \c e to \c n
+
+    /// Moves the target of \c e to \c n
+    ///
+    ///\note The <tt>Edge</tt>'s and <tt>OutEdge</tt>'s
+    ///referencing the moved edge remain
+    ///valid. However <tt>InEdge</tt>'s are invalidated.
+    void moveTarget(Edge e, Node n) { _moveTarget(e,n); }
+    /// Moves the source of \c e to \c n
+
+    /// Moves the source of \c e to \c n
+    ///
+    ///\note The <tt>Edge</tt>'s and <tt>InEdge</tt>'s
+    ///referencing the moved edge remain
+    ///valid. However <tt>OutEdge</tt>'s are invalidated.
+    void moveSource(Edge e, Node n) { _moveSource(e,n); }
+
+    /// Invert the direction of an edge.
+
+    ///\note The <tt>Edge</tt>'s
+    ///referencing the moved edge remain
+    ///valid. However <tt>OutEdge</tt>'s  and <tt>InEdge</tt>'s are invalidated.
+    void reverseEdge(Edge e) {
+      Node t=target(e);
+      _moveTarget(e,source(e));
+      _moveSource(e,t);
+    }
+
+    ///Using this it possible to avoid the superfluous memory allocation.
+
+    ///Using this it possible to avoid the superfluous memory allocation.
+    ///\todo more docs...
+    void reserveEdge(int n) { edges.reserve(n); };
+
+    ///Contract two nodes.
+
+    ///This function contracts two nodes.
+    ///
+    ///Node \p b will be removed but instead of deleting
+    ///its neighboring edges, they will be joined to \p a.
+    ///The last parameter \p r controls whether to remove loops. \c true
+    ///means that loops will be removed.
+    ///
+    ///\note The <tt>Edge</tt>s
+    ///referencing a moved edge remain
+    ///valid. However <tt>InEdge</tt>'s and <tt>OutEdge</tt>'s
+    ///may be invalidated.
+    void contract(Node a,Node b,bool r=true) 
+    {
+      for(OutEdgeIt e(*this,b);e!=INVALID;) {
+	OutEdgeIt f=e;
+	++f;
+	if(r && target(e)==a) erase(e);
+	else moveSource(e,a);
+	e=f;
+      }
+      for(InEdgeIt e(*this,b);e!=INVALID;) {
+	InEdgeIt f=e;
+	++f;
+	if(r && source(e)==a) erase(e);
+	else moveTarget(e,a);
+	e=f;
+      }
+      erase(b);
+    }
+
+    ///Split a node.
+
+    ///This function splits a node. First a new node is added to the graph,
+    ///then the source of each outgoing edge of \c n is moved to this new node.
+    ///If \c connect is \c true (this is the default value), then a new edge
+    ///from \c n to the newly created node is also added.
+    ///\return The newly created node.
+    ///
+    ///\note The <tt>Edge</tt>s
+    ///referencing a moved edge remain
+    ///valid. However <tt>InEdge</tt>'s and <tt>OutEdge</tt>'s
+    ///may be invalidated.
+    ///\warning This functionality cannot be used together with the SnapShot
+    ///feature.
+    ///\todo It could be implemented in a bit faster way.
+    Node split(Node n, bool connect = true) 
+    {
+      Node b = addNode();
+      for(OutEdgeIt e(*this,n);e!=INVALID;) {
+ 	OutEdgeIt f=e;
+	++f;
+	moveSource(e,b);
+	e=f;
+      }
+      if(connect) addEdge(n,b);
+      return b;
+    }
+      
+    ///Class to make a snapshot of the graph and to restrore to it later.
+
+    ///Class to make a snapshot of the graph and to restrore to it later.
+    ///
+    ///The newly added nodes and edges can be removed using the
+    ///restore() function.
+    ///
+    ///\warning Edge and node deletions cannot be restored.
+    ///\warning SnapShots cannot be nested.
+    ///\todo \c SnapShot or \c Snapshot?
+    class SnapShot : protected AlterationNotifier<Node>::ObserverBase,
+		     protected AlterationNotifier<Edge>::ObserverBase
+    {
+      protected:
+      
+      ListGraph *g;
+      std::list<Node> added_nodes;
+      std::list<Edge> added_edges;
+      
+      bool active;
+      virtual void add(const Node& n) {
+	added_nodes.push_back(n);
+      };
+      ///\bug Exception...
+      ///
+      virtual void erase(const Node&) 
+      {
+	exit(1);
+      }
+      virtual void add(const Edge& n) {
+	added_edges.push_back(n);
+      };
+      ///\bug Exception...
+      ///
+      virtual void erase(const Edge&) 
+      {
+	exit(1);
+      }
+
+      void regist(ListGraph &_g) {
+	g=&_g;
+	AlterationNotifier<Node>::ObserverBase::
+	  attach(g->getNotifier(Node()));
+	AlterationNotifier<Edge>::ObserverBase::
+	  attach(g->getNotifier(Edge()));
+      }
+            
+      void deregist() {
+	AlterationNotifier<Node>::ObserverBase::
+	  detach();
+	AlterationNotifier<Edge>::ObserverBase::
+	  detach();
+	g=0;
+      }
+            
+    public:
+      ///Default constructur.
+      
+      ///Default constructur.
+      ///To actually make a snapshot you must call save().
+      ///
+      SnapShot() : g(0) {}
+      ///Constructor that immediately makes a snapshot.
+      
+      ///This constructor immediately makes a snapshot of the graph.
+      ///\param _g The graph we make a snapshot of.
+      SnapShot(ListGraph &_g) {
+	regist(_g);
+      }
+      ///\bug Is it necessary?
+      ///
+      ~SnapShot() 
+      {
+	if(g) deregist();
+      }
+      
+      ///Make a snapshot.
+
+      ///Make a snapshot of the graph.
+      ///
+      ///This function can be called more than once. In case of a repeated
+      ///call, the previous snapshot gets lost.
+      ///\param _g The graph we make the snapshot of.
+      void save(ListGraph &_g) 
+      {
+	if(g!=&_g) {
+	  if(g) deregist();
+	  regist(_g);
+	}
+	added_nodes.clear();
+	added_edges.clear();
+      }
+      
+    ///Undo the changes until the last snapshot.
+
+    ///Undo the changes until last snapshot created by save().
+    ///
+    ///\todo This function might be called undo().
+      void restore() {
+	deregist();
+	while(!added_edges.empty()) {
+	  g->erase(added_edges.front());
+	  added_edges.pop_front();
+	}
+ 	while(!added_nodes.empty()) {
+	  g->erase(added_nodes.front());
+	  added_nodes.pop_front();
+	}
+      }
+    };
+    
+  };
+
+
+  /**************** Undirected List Graph ****************/
+
+  typedef ErasableUndirGraphExtender<
+    ClearableUndirGraphExtender<
+    ExtendableUndirGraphExtender<
+    MappableUndirGraphExtender<
+    IterableUndirGraphExtender<
+    AlterableUndirGraphExtender<
+    UndirGraphExtender<ListGraphBase> > > > > > > ErasableUndirListGraphBase;
+
+  ///An undirected list graph class.
+
+  ///This is a simple and fast erasable undirected graph implementation.
+  ///
+  ///It conforms to the
+  ///\ref concept::UndirGraph "UndirGraph" concept.
+  ///
+  ///\sa concept::UndirGraph.
+  ///
+  ///\todo SnapShot, reverseEdge(), moveTarget(), moveSource(), contract()
+  ///haven't been implemented yet.
+  ///
+  class UndirListGraph : public ErasableUndirListGraphBase {
+  };
+
+  
+  /// @}  
+} //namespace lemon
+  
+
+#endif