COIN-OR::LEMON - Graph Library

source: lemon-0.x/src/lemon/full_graph.h @ 1190:477a0fe37552

Last change on this file since 1190:477a0fe37552 was 1164:80bb73097736, checked in by Alpar Juttner, 19 years ago

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1/* -*- C++ -*-
2 * src/lemon/full_graph.h - Part of LEMON, a generic C++ optimization library
3 *
4 * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
5 * (Egervary Combinatorial Optimization Research Group, 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_FULL_GRAPH_H
18#define LEMON_FULL_GRAPH_H
19
20#include <cmath>
21
22
23#include <lemon/iterable_graph_extender.h>
24#include <lemon/alteration_notifier.h>
25#include <lemon/default_map.h>
26
27#include <lemon/invalid.h>
28#include <lemon/utility.h>
29
30
31///\ingroup graphs
32///\file
33///\brief FullGraph and SymFullGraph classes.
34
35
36namespace lemon {
37
38/// \addtogroup graphs
39/// @{
40
41  class FullGraphBase {
42    int NodeNum;
43    int EdgeNum;
44  public:
45
46    typedef FullGraphBase Graph;
47
48    class Node;
49    class Edge;
50
51  public:
52
53    FullGraphBase() {}
54
55
56    ///Creates a full graph with \c n nodes.
57    void construct(int n) { NodeNum = n; EdgeNum = n * n; }
58    ///
59    //    FullGraphBase(const FullGraphBase &_g)
60    //      : NodeNum(_g.nodeNum()), EdgeNum(NodeNum*NodeNum) { }
61   
62    typedef True NodeNumTag;
63    typedef True EdgeNumTag;
64
65    ///Number of nodes.
66    int nodeNum() const { return NodeNum; }
67    ///Number of edges.
68    int edgeNum() const { return EdgeNum; }
69
70    /// Maximum node ID.
71   
72    /// Maximum node ID.
73    ///\sa id(Node)
74    int maxId(Node = INVALID) const { return NodeNum-1; }
75    /// Maximum edge ID.
76   
77    /// Maximum edge ID.
78    ///\sa id(Edge)
79    int maxId(Edge = INVALID) const { return EdgeNum-1; }
80
81    Node source(Edge e) const { return e.id % NodeNum; }
82    Node target(Edge e) const { return e.id / NodeNum; }
83
84
85    /// Node ID.
86   
87    /// The ID of a valid Node is a nonnegative integer not greater than
88    /// \ref maxNodeId(). The range of the ID's is not surely continuous
89    /// and the greatest node ID can be actually less then \ref maxNodeId().
90    ///
91    /// The ID of the \ref INVALID node is -1.
92    ///\return The ID of the node \c v.
93
94    static int id(Node v) { return v.id; }
95    /// Edge ID.
96   
97    /// The ID of a valid Edge is a nonnegative integer not greater than
98    /// \ref maxEdgeId(). The range of the ID's is not surely continuous
99    /// and the greatest edge ID can be actually less then \ref maxEdgeId().
100    ///
101    /// The ID of the \ref INVALID edge is -1.
102    ///\return The ID of the edge \c e.
103    static int id(Edge e) { return e.id; }
104
105    static Node fromId(int id, Node) { return Node(id);}
106   
107    static Edge fromId(int id, Edge) { return Edge(id);}
108
109    /// Finds an edge between two nodes.
110   
111    /// Finds an edge from node \c u to node \c v.
112    ///
113    /// If \c prev is \ref INVALID (this is the default value), then
114    /// It finds the first edge from \c u to \c v. Otherwise it looks for
115    /// the next edge from \c u to \c v after \c prev.
116    /// \return The found edge or INVALID if there is no such an edge.
117    Edge findEdge(Node u,Node v, Edge prev = INVALID)
118    {
119      return prev.id == -1 ? Edge(*this, u.id, v.id) : INVALID;
120    }
121   
122     
123    class Node {
124      friend class FullGraphBase;
125
126    protected:
127      int id;
128      Node(int _id) { id = _id;}
129    public:
130      Node() {}
131      Node (Invalid) { id = -1; }
132      bool operator==(const Node node) const {return id == node.id;}
133      bool operator!=(const Node node) const {return id != node.id;}
134      bool operator<(const Node node) const {return id < node.id;}
135    };
136   
137
138
139    class Edge {
140      friend class FullGraphBase;
141     
142    protected:
143      int id;  // NodeNum * target + source;
144
145      Edge(int _id) : id(_id) {}
146
147      Edge(const FullGraphBase& _graph, int source, int target)
148        : id(_graph.NodeNum * target+source) {}
149    public:
150      Edge() { }
151      Edge (Invalid) { id = -1; }
152      bool operator==(const Edge edge) const {return id == edge.id;}
153      bool operator!=(const Edge edge) const {return id != edge.id;}
154      bool operator<(const Edge edge) const {return id < edge.id;}
155    };
156
157    void first(Node& node) const {
158      node.id = NodeNum-1;
159    }
160
161    static void next(Node& node) {
162      --node.id;
163    }
164
165    void first(Edge& edge) const {
166      edge.id = EdgeNum-1;
167    }
168
169    static void next(Edge& edge) {
170      --edge.id;
171    }
172
173    void firstOut(Edge& edge, const Node& node) const {
174      edge.id = EdgeNum + node.id - NodeNum;
175    }
176
177    void nextOut(Edge& edge) const {
178      edge.id -= NodeNum;
179      if (edge.id < 0) edge.id = -1;
180    }
181
182    void firstIn(Edge& edge, const Node& node) const {
183      edge.id = node.id * NodeNum;
184    }
185   
186    void nextIn(Edge& edge) const {
187      ++edge.id;
188      if (edge.id % NodeNum == 0) edge.id = -1;
189    }
190
191  };
192
193
194  typedef AlterableGraphExtender<FullGraphBase> AlterableFullGraphBase;
195  typedef IterableGraphExtender<AlterableFullGraphBase> IterableFullGraphBase;
196  typedef DefaultMappableGraphExtender<IterableFullGraphBase> MappableFullGraphBase;
197
198  ///A full graph class.
199
200  ///This is a simple and fast directed full graph implementation.
201  ///It is completely static, so you can neither add nor delete either
202  ///edges or nodes.
203  ///Thus it conforms to
204  ///the \ref concept::StaticGraph "StaticGraph" concept
205  ///\sa concept::StaticGraph.
206  ///
207  ///\author Alpar Juttner
208  class FullGraph : public MappableFullGraphBase {
209  public:
210
211    FullGraph(int n) { construct(n); }
212  };
213
214
215  // Base graph class for UndirFullGraph.
216  class UndirFullGraphBase {
217    int NodeNum;
218    int EdgeNum;
219  public:
220
221    typedef UndirFullGraphBase Graph;
222
223    class Node;
224    class Edge;
225
226  public:
227
228    UndirFullGraphBase() {}
229
230
231    ///Creates a full graph with \c n nodes.
232    void construct(int n) { NodeNum = n; EdgeNum = n * (n - 1) / 2; }
233    ///
234    //    FullGraphBase(const FullGraphBase &_g)
235    //      : NodeNum(_g.nodeNum()), EdgeNum(NodeNum*NodeNum) { }
236   
237    typedef True NodeNumTag;
238    typedef True EdgeNumTag;
239
240    ///Number of nodes.
241    int nodeNum() const { return NodeNum; }
242    ///Number of edges.
243    int edgeNum() const { return EdgeNum; }
244
245    /// Maximum node ID.
246   
247    /// Maximum node ID.
248    ///\sa id(Node)
249    int maxId(Node = INVALID) const { return NodeNum-1; }
250    /// Maximum edge ID.
251   
252    /// Maximum edge ID.
253    ///\sa id(Edge)
254    int maxId(Edge = INVALID) const { return EdgeNum-1; }
255
256    Node source(Edge e) const {
257      /// \todo we may do it faster
258      return ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;
259    }
260
261    Node target(Edge e) const {
262      int source = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
263      return e.id - (source) * (source - 1) / 2;
264    }
265
266
267    /// Node ID.
268   
269    /// The ID of a valid Node is a nonnegative integer not greater than
270    /// \ref maxNodeId(). The range of the ID's is not surely continuous
271    /// and the greatest node ID can be actually less then \ref maxNodeId().
272    ///
273    /// The ID of the \ref INVALID node is -1.
274    ///\return The ID of the node \c v.
275
276    static int id(Node v) { return v.id; }
277    /// Edge ID.
278   
279    /// The ID of a valid Edge is a nonnegative integer not greater than
280    /// \ref maxEdgeId(). The range of the ID's is not surely continuous
281    /// and the greatest edge ID can be actually less then \ref maxEdgeId().
282    ///
283    /// The ID of the \ref INVALID edge is -1.
284    ///\return The ID of the edge \c e.
285    static int id(Edge e) { return e.id; }
286
287    /// Finds an edge between two nodes.
288   
289    /// Finds an edge from node \c u to node \c v.
290    ///
291    /// If \c prev is \ref INVALID (this is the default value), then
292    /// It finds the first edge from \c u to \c v. Otherwise it looks for
293    /// the next edge from \c u to \c v after \c prev.
294    /// \return The found edge or INVALID if there is no such an edge.
295    Edge findEdge(Node u,Node v, Edge prev = INVALID)
296    {
297      return prev.id == -1 ? Edge(*this, u.id, v.id) : INVALID;
298    }
299   
300     
301    class Node {
302      friend class UndirFullGraphBase;
303
304    protected:
305      int id;
306      Node(int _id) { id = _id;}
307    public:
308      Node() {}
309      Node (Invalid) { id = -1; }
310      bool operator==(const Node node) const {return id == node.id;}
311      bool operator!=(const Node node) const {return id != node.id;}
312      bool operator<(const Node node) const {return id < node.id;}
313    };
314   
315
316
317    class Edge {
318      friend class UndirFullGraphBase;
319     
320    protected:
321      int id;  // NodeNum * target + source;
322
323      Edge(int _id) : id(_id) {}
324
325      Edge(const UndirFullGraphBase& _graph, int source, int target)
326        : id(_graph.NodeNum * target+source) {}
327    public:
328      Edge() { }
329      Edge (Invalid) { id = -1; }
330      bool operator==(const Edge edge) const {return id == edge.id;}
331      bool operator!=(const Edge edge) const {return id != edge.id;}
332      bool operator<(const Edge edge) const {return id < edge.id;}
333    };
334
335    void first(Node& node) const {
336      node.id = NodeNum-1;
337    }
338
339    static void next(Node& node) {
340      --node.id;
341    }
342
343    void first(Edge& edge) const {
344      edge.id = EdgeNum-1;
345    }
346
347    static void next(Edge& edge) {
348      --edge.id;
349    }
350
351    void firstOut(Edge& edge, const Node& node) const {     
352      edge.id = node.id != 0 ? node.id * (node.id - 1) / 2 : -1;
353    }
354
355    /// \todo with specialized iterators we can make faster iterating
356    void nextOut(Edge& e) const {
357      int source = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
358      int target = e.id - (source) * (source - 1) / 2;
359      ++target;
360      e.id = target < source ? source * (source - 1) / 2 + target : -1;
361    }
362
363    void firstIn(Edge& edge, const Node& node) const {
364      edge.id = node.id * (node.id + 1) / 2 - 1;
365    }
366   
367    void nextIn(Edge& e) const {
368      int source = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
369      int target = e.id - (source) * (source - 1) / 2; ++target;
370      ++source;
371      e.id = source < NodeNum ? source * (source - 1) / 2 + target : -1;
372    }
373
374  };
375
376  /// \todo UndirFullGraph from the UndirFullGraphBase
377
378 
379
380  /// @} 
381
382} //namespace lemon
383
384
385#endif //LEMON_FULL_GRAPH_H
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