COIN-OR::LEMON - Graph Library

source: lemon-0.x/lemon/smart_graph.h @ 1933:a876a3d6a4c7

Last change on this file since 1933:a876a3d6a4c7 was 1910:f95eea8c34b0, checked in by Balazs Dezso, 14 years ago

Bipartite => Bp
Upper => A
Lower => B

+ some bug fix

File size: 15.4 KB
Line 
1/* -*- C++ -*-
2 * lemon/smart_graph.h - Part of LEMON, a generic C++ optimization library
3 *
4 * Copyright (C) 2006 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
5 * (Egervary Research Group on Combinatorial Optimization, EGRES).
6 *
7 * Permission to use, modify and distribute this software is granted
8 * provided that this copyright notice appears in all copies. For
9 * precise terms see the accompanying LICENSE file.
10 *
11 * This software is provided "AS IS" with no warranty of any kind,
12 * express or implied, and with no claim as to its suitability for any
13 * purpose.
14 *
15 */
16
17#ifndef LEMON_SMART_GRAPH_H
18#define LEMON_SMART_GRAPH_H
19
20///\ingroup graphs
21///\file
22///\brief SmartGraph and SmartUGraph classes.
23
24#include <vector>
25
26#include <lemon/invalid.h>
27
28#include <lemon/bits/clearable_graph_extender.h>
29#include <lemon/bits/extendable_graph_extender.h>
30#include <lemon/bits/iterable_graph_extender.h>
31#include <lemon/bits/alteration_notifier.h>
32#include <lemon/bits/default_map.h>
33#include <lemon/bits/graph_extender.h>
34
35#include <lemon/utility.h>
36#include <lemon/error.h>
37
38namespace lemon {
39
40  class SmartGraph;
41  ///Base of SmartGraph
42
43  ///Base of SmartGraph
44  ///
45  class SmartGraphBase {
46
47    friend class SmatGraph;
48
49  protected:
50    struct NodeT
51    {
52      int first_in,first_out;     
53      NodeT() : first_in(-1), first_out(-1) {}
54    };
55    struct EdgeT
56    {
57      int target, source, next_in, next_out;     
58      //FIXME: is this necessary?
59      EdgeT() : next_in(-1), next_out(-1) {} 
60    };
61
62    std::vector<NodeT> nodes;
63
64    std::vector<EdgeT> edges;
65   
66   
67  public:
68
69    typedef SmartGraphBase Graph;
70
71    class Node;
72    class Edge;
73
74   
75  public:
76
77    SmartGraphBase() : nodes(), edges() { }
78    SmartGraphBase(const SmartGraphBase &_g)
79      : nodes(_g.nodes), edges(_g.edges) { }
80   
81    typedef True NodeNumTag;
82    typedef True EdgeNumTag;
83
84    ///Number of nodes.
85    int nodeNum() const { return nodes.size(); }
86    ///Number of edges.
87    int edgeNum() const { return edges.size(); }
88
89    /// Maximum node ID.
90   
91    /// Maximum node ID.
92    ///\sa id(Node)
93    int maxNodeId() const { return nodes.size()-1; }
94    /// Maximum edge ID.
95   
96    /// Maximum edge ID.
97    ///\sa id(Edge)
98    int maxEdgeId() const { return edges.size()-1; }
99
100    Node source(Edge e) const { return edges[e.n].source; }
101    Node target(Edge e) const { return edges[e.n].target; }
102
103    /// Node ID.
104   
105    /// The ID of a valid Node is a nonnegative integer not greater than
106    /// \ref maxNodeId(). The range of the ID's is not surely continuous
107    /// and the greatest node ID can be actually less then \ref maxNodeId().
108    ///
109    /// The ID of the \ref INVALID node is -1.
110    ///\return The ID of the node \c v.
111    static int id(Node v) { return v.n; }
112    /// Edge ID.
113   
114    /// The ID of a valid Edge is a nonnegative integer not greater than
115    /// \ref maxEdgeId(). The range of the ID's is not surely continuous
116    /// and the greatest edge ID can be actually less then \ref maxEdgeId().
117    ///
118    /// The ID of the \ref INVALID edge is -1.
119    ///\return The ID of the edge \c e.
120    static int id(Edge e) { return e.n; }
121
122    static Node nodeFromId(int id) { return Node(id);}
123
124    static Edge edgeFromId(int id) { return Edge(id);}
125
126    Node addNode() {
127      Node n; n.n=nodes.size();
128      nodes.push_back(NodeT()); //FIXME: Hmmm...
129      return n;
130    }
131   
132    Edge addEdge(Node u, Node v) {
133      Edge e; e.n=edges.size(); edges.push_back(EdgeT()); //FIXME: Hmmm...
134      edges[e.n].source=u.n; edges[e.n].target=v.n;
135      edges[e.n].next_out=nodes[u.n].first_out;
136      edges[e.n].next_in=nodes[v.n].first_in;
137      nodes[u.n].first_out=nodes[v.n].first_in=e.n;
138
139      return e;
140    }
141
142    void clear() {
143      edges.clear();
144      nodes.clear();
145    }
146
147
148    class Node {
149      friend class SmartGraphBase;
150      friend class SmartGraph;
151
152    protected:
153      int n;
154      Node(int nn) {n=nn;}
155    public:
156      Node() {}
157      Node (Invalid) { n=-1; }
158      bool operator==(const Node i) const {return n==i.n;}
159      bool operator!=(const Node i) const {return n!=i.n;}
160      bool operator<(const Node i) const {return n<i.n;}
161    };
162   
163
164    class Edge {
165      friend class SmartGraphBase;
166      friend class SmartGraph;
167
168    protected:
169      int n;
170      Edge(int nn) {n=nn;}
171    public:
172      Edge() { }
173      Edge (Invalid) { n=-1; }
174      bool operator==(const Edge i) const {return n==i.n;}
175      bool operator!=(const Edge i) const {return n!=i.n;}
176      bool operator<(const Edge i) const {return n<i.n;}
177    };
178
179    void first(Node& node) const {
180      node.n = nodes.size() - 1;
181    }
182
183    static void next(Node& node) {
184      --node.n;
185    }
186
187    void first(Edge& edge) const {
188      edge.n = edges.size() - 1;
189    }
190
191    static void next(Edge& edge) {
192      --edge.n;
193    }
194
195    void firstOut(Edge& edge, const Node& node) const {
196      edge.n = nodes[node.n].first_out;
197    }
198
199    void nextOut(Edge& edge) const {
200      edge.n = edges[edge.n].next_out;
201    }
202
203    void firstIn(Edge& edge, const Node& node) const {
204      edge.n = nodes[node.n].first_in;
205    }
206   
207    void nextIn(Edge& edge) const {
208      edge.n = edges[edge.n].next_in;
209    }
210
211    Node _split(Node n, bool connect = true)
212    {
213      Node b = addNode();
214      nodes[b.n].first_out=nodes[n.n].first_out;
215      nodes[n.n].first_out=-1;
216      for(int i=nodes[b.n].first_out;i!=-1;i++) edges[i].source=b.n;
217      if(connect) addEdge(n,b);
218      return b;
219    }
220
221  };
222
223  typedef ClearableGraphExtender<
224    ExtendableGraphExtender<
225    MappableGraphExtender<
226    IterableGraphExtender<
227    AlterableGraphExtender<
228    GraphExtender<SmartGraphBase> > > > > > ExtendedSmartGraphBase;
229
230  /// \ingroup graphs
231
232  ///A smart graph class.
233
234  ///This is a simple and fast graph implementation.
235  ///It is also quite memory efficient, but at the price
236  ///that <b> it does support only limited (only stack-like)
237  ///node and edge deletions</b>.
238  ///It conforms to
239  ///the \ref concept::ExtendableGraph "ExtendableGraph" concept.
240  ///\sa concept::ExtendableGraph.
241  ///
242  ///\author Alpar Juttner
243  class SmartGraph : public ExtendedSmartGraphBase {
244  public:
245   
246    class Snapshot;
247    friend class Snapshot;
248
249  protected:
250    void restoreSnapshot(const Snapshot &s)
251    {
252      while(s.edge_num<edges.size()) {
253        Parent::getNotifier(Edge()).erase(Edge(edges.size()-1));
254        nodes[edges.back().target].first_in=edges.back().next_in;
255        nodes[edges.back().source].first_out=edges.back().next_out;
256        edges.pop_back();
257      }
258      //nodes.resize(s.nodes_num);
259      while(s.node_num<nodes.size()) {
260        Parent::getNotifier(Node()).erase(Node(nodes.size()-1));
261        nodes.pop_back();
262      }
263    }   
264
265  public:
266
267    ///Split a node.
268   
269    ///This function splits a node. First a new node is added to the graph,
270    ///then the source of each outgoing edge of \c n is moved to this new node.
271    ///If \c connect is \c true (this is the default value), then a new edge
272    ///from \c n to the newly created node is also added.
273    ///\return The newly created node.
274    ///
275    ///\note The <tt>Edge</tt>s
276    ///referencing a moved edge remain
277    ///valid. However <tt>InEdge</tt>'s and <tt>OutEdge</tt>'s
278    ///may be invalidated.
279    ///\warning This functionality cannot be used together with the Snapshot
280    ///feature.
281    ///\todo It could be implemented in a bit faster way.
282    Node split(Node n, bool connect = true)
283    {
284      Node b = _split(n,connect);
285      return b;
286    }
287 
288
289    ///Class to make a snapshot of the graph and to restrore to it later.
290
291    ///Class to make a snapshot of the graph and to restrore to it later.
292    ///
293    ///The newly added nodes and edges can be removed using the
294    ///restore() function.
295    ///\note After you restore a state, you cannot restore
296    ///a later state, in other word you cannot add again the edges deleted
297    ///by restore() using another Snapshot instance.
298    ///
299    class Snapshot
300    {
301      SmartGraph *g;
302    protected:
303      friend class SmartGraph;
304      unsigned int node_num;
305      unsigned int edge_num;
306    public:
307      ///Default constructor.
308     
309      ///Default constructor.
310      ///To actually make a snapshot you must call save().
311      ///
312      Snapshot() : g(0) {}
313      ///Constructor that immediately makes a snapshot
314     
315      ///This constructor immediately makes a snapshot of the graph.
316      ///\param _g The graph we make a snapshot of.
317      Snapshot(SmartGraph &_g) :g(&_g) {
318        node_num=g->nodes.size();
319        edge_num=g->edges.size();
320      }
321
322      ///Make a snapshot.
323
324      ///Make a snapshot of the graph.
325      ///
326      ///This function can be called more than once. In case of a repeated
327      ///call, the previous snapshot gets lost.
328      ///\param _g The graph we make the snapshot of.
329      void save(SmartGraph &_g)
330      {
331        g=&_g;
332        node_num=g->nodes.size();
333        edge_num=g->edges.size();
334      }
335
336      ///Undo the changes until a snapshot.
337     
338      ///Undo the changes until a snapshot created by save().
339      ///
340      ///\note After you restored a state, you cannot restore
341      ///a later state, in other word you cannot add again the edges deleted
342      ///by restore().
343      ///
344      ///\todo This function might be called undo().
345     
346      void restore()
347      {
348        g->restoreSnapshot(*this);
349      }
350    };
351  };
352
353
354  /**************** Undirected List Graph ****************/
355
356  typedef ClearableUGraphExtender<
357    ExtendableUGraphExtender<
358    MappableUGraphExtender<
359    IterableUGraphExtender<
360    AlterableUGraphExtender<
361    UGraphExtender<SmartGraphBase> > > > > > ExtendedSmartUGraphBase;
362
363  /// \ingroup graphs
364  ///
365  /// \brief A smart undirected graph class.
366  ///
367  /// This is a simple and fast undirected graph implementation.
368  /// It is also quite memory efficient, but at the price
369  /// that <b> it does support only limited (only stack-like)
370  /// node and edge deletions</b>.
371  /// Except from this it conforms to
372  /// the \ref concept::UGraph "UGraph" concept.
373  /// \sa concept::UGraph.
374  ///
375  /// \todo Snapshot hasn't been implemented yet.
376  ///
377  class SmartUGraph : public ExtendedSmartUGraphBase {
378  };
379
380
381  class SmartBpUGraphBase {
382  public:
383
384    class NodeSetError : public LogicError {
385      virtual const char* exceptionName() const {
386        return "lemon::SmartBpUGraph::NodeSetError";
387      }
388    };
389
390  protected:
391
392    struct NodeT {
393      int first;
394      NodeT() {}
395      NodeT(int _first) : first(_first) {}
396    };
397
398    struct EdgeT {
399      int aNode, next_out;
400      int bNode, next_in;
401    };
402
403    std::vector<NodeT> aNodes;
404    std::vector<NodeT> bNodes;
405
406    std::vector<EdgeT> edges;
407
408  public:
409 
410    class Node {
411      friend class SmartBpUGraphBase;
412    protected:
413      int id;
414
415      Node(int _id) : id(_id) {}
416    public:
417      Node() {}
418      Node(Invalid) { id = -1; }
419      bool operator==(const Node i) const {return id==i.id;}
420      bool operator!=(const Node i) const {return id!=i.id;}
421      bool operator<(const Node i) const {return id<i.id;}
422    };
423
424    class Edge {
425      friend class SmartBpUGraphBase;
426    protected:
427      int id;
428
429      Edge(int _id) { id = _id;}
430    public:
431      Edge() {}
432      Edge (Invalid) { id = -1; }
433      bool operator==(const Edge i) const {return id==i.id;}
434      bool operator!=(const Edge i) const {return id!=i.id;}
435      bool operator<(const Edge i) const {return id<i.id;}
436    };
437
438    void firstANode(Node& node) const {
439      node.id = 2 * aNodes.size() - 2;
440      if (node.id < 0) node.id = -1;
441    }
442    void nextANode(Node& node) const {
443      node.id -= 2;
444      if (node.id < 0) node.id = -1;
445    }
446
447    void firstBNode(Node& node) const {
448      node.id = 2 * bNodes.size() - 1;
449    }
450    void nextBNode(Node& node) const {
451      node.id -= 2;
452    }
453
454    void first(Node& node) const {
455      if (aNodes.size() > 0) {
456        node.id = 2 * aNodes.size() - 2;
457      } else {
458        node.id = 2 * bNodes.size() - 1;
459      }
460    }
461    void next(Node& node) const {
462      node.id -= 2;
463      if (node.id == -2) {
464        node.id = 2 * bNodes.size() - 1;
465      }
466    }
467 
468    void first(Edge& edge) const {
469      edge.id = edges.size() - 1;
470    }
471    void next(Edge& edge) const {
472      --edge.id;
473    }
474
475    void firstOut(Edge& edge, const Node& node) const {
476      LEMON_ASSERT((node.id & 1) == 0, NodeSetError());
477      edge.id = aNodes[node.id >> 1].first;
478    }
479    void nextOut(Edge& edge) const {
480      edge.id = edges[edge.id].next_out;
481    }
482
483    void firstIn(Edge& edge, const Node& node) const {
484      LEMON_ASSERT((node.id & 1) == 1, NodeSetError());
485      edge.id = bNodes[node.id >> 1].first;
486    }
487    void nextIn(Edge& edge) const {
488      edge.id = edges[edge.id].next_in;
489    }
490
491    static int id(const Node& node) {
492      return node.id;
493    }
494    static Node nodeFromId(int id) {
495      return Node(id);
496    }
497    int maxNodeId() const {
498      return aNodes.size() > bNodes.size() ?
499        aNodes.size() * 2 - 2 : bNodes.size() * 2 - 1;
500    }
501 
502    static int id(const Edge& edge) {
503      return edge.id;
504    }
505    static Edge edgeFromId(int id) {
506      return Edge(id);
507    }
508    int maxEdgeId() const {
509      return edges.size();
510    }
511 
512    static int aNodeId(const Node& node) {
513      return node.id >> 1;
514    }
515    static Node fromANodeId(int id, Node) {
516      return Node(id << 1);
517    }
518    int maxANodeId() const {
519      return aNodes.size();
520    }
521
522    static int bNodeId(const Node& node) {
523      return node.id >> 1;
524    }
525    static Node fromBNodeId(int id) {
526      return Node((id << 1) + 1);
527    }
528    int maxBNodeId() const {
529      return bNodes.size();
530    }
531
532    Node aNode(const Edge& edge) const {
533      return Node(edges[edge.id].aNode);
534    }
535    Node bNode(const Edge& edge) const {
536      return Node(edges[edge.id].bNode);
537    }
538
539    static bool aNode(const Node& node) {
540      return (node.id & 1) == 0;
541    }
542
543    static bool bNode(const Node& node) {
544      return (node.id & 1) == 1;
545    }
546
547    Node addANode() {
548      NodeT nodeT;
549      nodeT.first = -1;
550      aNodes.push_back(nodeT);
551      return Node(aNodes.size() * 2 - 2);
552    }
553
554    Node addBNode() {
555      NodeT nodeT;
556      nodeT.first = -1;
557      bNodes.push_back(nodeT);
558      return Node(bNodes.size() * 2 - 1);
559    }
560
561    Edge addEdge(const Node& source, const Node& target) {
562      LEMON_ASSERT(((source.id ^ target.id) & 1) == 1, NodeSetError());
563      EdgeT edgeT;
564      if ((source.id & 1) == 0) {
565        edgeT.aNode = source.id;
566        edgeT.bNode = target.id;
567      } else {
568        edgeT.aNode = target.id;
569        edgeT.bNode = source.id;
570      }
571      edgeT.next_out = aNodes[edgeT.aNode >> 1].first;
572      aNodes[edgeT.aNode >> 1].first = edges.size();
573      edgeT.next_in = bNodes[edgeT.bNode >> 1].first;
574      bNodes[edgeT.bNode >> 1].first = edges.size();
575      edges.push_back(edgeT);
576      return Edge(edges.size() - 1);
577    }
578
579    void clear() {
580      aNodes.clear();
581      bNodes.clear();
582      edges.clear();
583    }
584
585  };
586
587
588  typedef ClearableBpUGraphExtender<
589    ExtendableBpUGraphExtender<
590    MappableBpUGraphExtender<
591    IterableBpUGraphExtender<
592    AlterableBpUGraphExtender<
593    BpUGraphExtender <
594    SmartBpUGraphBase> > > > > >
595  ExtendedSmartBpUGraphBase;
596
597  /// \ingroup graphs
598  ///
599  /// \brief A smart bipartite undirected graph class.
600  ///
601  /// This is a simple and fast bipartite undirected graph implementation.
602  /// It is also quite memory efficient, but at the price
603  /// that <b> it does not support node and edge deletions</b>.
604  /// Except from this it conforms to
605  /// the \ref concept::BpUGraph "BpUGraph" concept.
606  /// \sa concept::BpUGraph.
607  ///
608  class SmartBpUGraph : public ExtendedSmartBpUGraphBase {};
609
610 
611  /// @} 
612} //namespace lemon
613
614
615#endif //LEMON_SMART_GRAPH_H
Note: See TracBrowser for help on using the repository browser.