COIN-OR::LEMON - Graph Library

source: lemon-0.x/lemon/smart_graph.h @ 1865:dcefd1d1377f

Last change on this file since 1865:dcefd1d1377f was 1820:22099ef840d7, checked in by Balazs Dezso, 18 years ago

Undir Bipartite Graph/Full? and Smart/ without concept, doc and concept
checking

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1/* -*- C++ -*-
2 * lemon/smart_graph.h - Part of LEMON, a generic C++ optimization library
3 *
4 * Copyright (C) 2005 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 UndirSmartGraph 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 ClearableUndirGraphExtender<
357    ExtendableUndirGraphExtender<
358    MappableUndirGraphExtender<
359    IterableUndirGraphExtender<
360    AlterableUndirGraphExtender<
361    UndirGraphExtender<SmartGraphBase> > > > > > ExtendedUndirSmartGraphBase;
362
363  ///A smart undirected graph class.
364
365  ///This is a simple and fast undirected graph implementation.
366  ///It is also quite memory efficient, but at the price
367  ///that <b> it does support only limited (only stack-like)
368  ///node and edge deletions</b>.
369  ///Except from this it conforms to
370  ///the \ref concept::UndirGraph "UndirGraph" concept.
371  ///\sa concept::UndirGraph.
372  ///
373  ///\todo Snapshot hasn't been implemented yet.
374  ///
375  class UndirSmartGraph : public ExtendedUndirSmartGraphBase {
376  };
377
378
379  class SmartUndirBipartiteGraphBase {
380  public:
381
382    class NodeSetError : public LogicError {
383      virtual const char* exceptionName() const {
384        return "lemon::FullUndirBipartiteGraph::NodeSetError";
385      }
386    };
387
388  protected:
389
390    struct NodeT {
391      int first;
392      NodeT() {}
393      NodeT(int _first) : first(_first) {}
394    };
395
396    struct EdgeT {
397      int upper, next_down;
398      int lower, next_up;
399    };
400
401    std::vector<NodeT> upperNodes;
402    std::vector<NodeT> lowerNodes;
403
404    std::vector<EdgeT> edges;
405
406  public:
407 
408    class Node {
409      friend class SmartUndirBipartiteGraphBase;
410    protected:
411      int id;
412
413      Node(int _id) : id(_id) {}
414    public:
415      Node() {}
416      Node(Invalid) { id = -1; }
417      bool operator==(const Node i) const {return id==i.id;}
418      bool operator!=(const Node i) const {return id!=i.id;}
419      bool operator<(const Node i) const {return id<i.id;}
420    };
421
422    class Edge {
423      friend class SmartUndirBipartiteGraphBase;
424    protected:
425      int id;
426
427      Edge(int _id) { id = _id;}
428    public:
429      Edge() {}
430      Edge (Invalid) { id = -1; }
431      bool operator==(const Edge i) const {return id==i.id;}
432      bool operator!=(const Edge i) const {return id!=i.id;}
433      bool operator<(const Edge i) const {return id<i.id;}
434    };
435
436    void firstUpper(Node& node) const {
437      node.id = 2 * upperNodes.size() - 2;
438      if (node.id < 0) node.id = -1;
439    }
440    void nextUpper(Node& node) const {
441      node.id -= 2;
442      if (node.id < 0) node.id = -1;
443    }
444
445    void firstLower(Node& node) const {
446      node.id = 2 * lowerNodes.size() - 1;
447    }
448    void nextLower(Node& node) const {
449      node.id -= 2;
450    }
451
452    void first(Node& node) const {
453      if (upperNodes.size() > 0) {
454        node.id = 2 * upperNodes.size() - 2;
455      } else {
456        node.id = 2 * lowerNodes.size() - 1;
457      }
458    }
459    void next(Node& node) const {
460      node.id -= 2;
461      if (node.id == -2) {
462        node.id = 2 * lowerNodes.size() - 1;
463      }
464    }
465 
466    void first(Edge& edge) const {
467      edge.id = edges.size() - 1;
468    }
469    void next(Edge& edge) const {
470      --edge.id;
471    }
472
473    void firstDown(Edge& edge, const Node& node) const {
474      LEMON_ASSERT((node.id & 1) == 0, NodeSetError());
475      edge.id = upperNodes[node.id >> 1].first;
476    }
477    void nextDown(Edge& edge) const {
478      edge.id = edges[edge.id].next_down;
479    }
480
481    void firstUp(Edge& edge, const Node& node) const {
482      LEMON_ASSERT((node.id & 1) == 1, NodeSetError());
483      edge.id = lowerNodes[node.id >> 1].first;
484    }
485    void nextUp(Edge& edge) const {
486      edge.id = edges[edge.id].next_up;
487    }
488
489    static int id(const Node& node) {
490      return node.id;
491    }
492    static Node nodeFromId(int id) {
493      return Node(id);
494    }
495    int maxNodeId() const {
496      return upperNodes.size() > lowerNodes.size() ?
497        upperNodes.size() * 2 - 2 : lowerNodes.size() * 2 - 1;
498    }
499 
500    static int id(const Edge& edge) {
501      return edge.id;
502    }
503    static Edge edgeFromId(int id) {
504      return Edge(id);
505    }
506    int maxEdgeId() const {
507      return edges.size();
508    }
509 
510    static int upperId(const Node& node) {
511      return node.id >> 1;
512    }
513    static Node fromUpperId(int id, Node) {
514      return Node(id << 1);
515    }
516    int maxUpperId() const {
517      return upperNodes.size();
518    }
519
520    static int lowerId(const Node& node) {
521      return node.id >> 1;
522    }
523    static Node fromLowerId(int id) {
524      return Node((id << 1) + 1);
525    }
526    int maxLowerId() const {
527      return lowerNodes.size();
528    }
529
530    Node upperNode(const Edge& edge) const {
531      return Node(edges[edge.id].upper);
532    }
533    Node lowerNode(const Edge& edge) const {
534      return Node(edges[edge.id].lower);
535    }
536
537    static bool upper(const Node& node) {
538      return (node.id & 1) == 0;
539    }
540
541    static bool lower(const Node& node) {
542      return (node.id & 1) == 1;
543    }
544
545    Node addUpperNode() {
546      NodeT nodeT;
547      nodeT.first = -1;
548      upperNodes.push_back(nodeT);
549      return Node(upperNodes.size() * 2 - 2);
550    }
551
552    Node addLowerNode() {
553      NodeT nodeT;
554      nodeT.first = -1;
555      lowerNodes.push_back(nodeT);
556      return Node(lowerNodes.size() * 2 - 1);
557    }
558
559    Edge addEdge(const Node& source, const Node& target) {
560      LEMON_ASSERT(((source.id ^ target.id) & 1) == 1, NodeSetError());
561      EdgeT edgeT;
562      if ((source.id & 1) == 0) {
563        edgeT.upper = source.id;
564        edgeT.lower = target.id;
565      } else {
566        edgeT.upper = target.id;
567        edgeT.lower = source.id;
568      }
569      edgeT.next_down = upperNodes[edgeT.upper >> 1].first;
570      upperNodes[edgeT.upper >> 1].first = edges.size();
571      edgeT.next_up = lowerNodes[edgeT.lower >> 1].first;
572      lowerNodes[edgeT.lower >> 1].first = edges.size();
573      edges.push_back(edgeT);
574      return Edge(edges.size() - 1);
575    }
576
577    void clear() {
578      upperNodes.clear();
579      lowerNodes.clear();
580      edges.clear();
581    }
582
583  };
584
585
586  typedef ClearableUndirBipartiteGraphExtender<
587    ExtendableUndirBipartiteGraphExtender<
588    MappableUndirBipartiteGraphExtender<
589    IterableUndirBipartiteGraphExtender<
590    AlterableUndirBipartiteGraphExtender<
591    UndirBipartiteGraphExtender <
592    SmartUndirBipartiteGraphBase> > > > > >
593  ExtendedSmartUndirBipartiteGraphBase;
594
595
596  class SmartUndirBipartiteGraph :
597    public ExtendedSmartUndirBipartiteGraphBase {
598  };
599
600 
601  /// @} 
602} //namespace lemon
603
604
605#endif //LEMON_SMART_GRAPH_H
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