COIN-OR::LEMON - Graph Library

source: lemon-0.x/src/lemon/full_graph.h @ 983:3095ff2b5c18

Last change on this file since 983:3095ff2b5c18 was 983:3095ff2b5c18, checked in by Balazs Dezso, 15 years ago

UndirFullGraphBase? is added
It is a graph base which contains only one way directed edges in a full graph.

File size: 9.9 KB
Line 
1/* -*- C++ -*-
2 * src/lemon/full_graph.h - Part of LEMON, a generic C++ optimization library
3 *
4 * Copyright (C) 2004 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_observer_registry.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 tail(Edge e) const { return e.id % NodeNum; }
82    Node head(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    /// Finds an edge between two nodes.
106   
107    /// Finds an edge from node \c u to node \c v.
108    ///
109    /// If \c prev is \ref INVALID (this is the default value), then
110    /// It finds the first edge from \c u to \c v. Otherwise it looks for
111    /// the next edge from \c u to \c v after \c prev.
112    /// \return The found edge or INVALID if there is no such an edge.
113    Edge findEdge(Node u,Node v, Edge prev = INVALID)
114    {
115      return prev.id == -1 ? Edge(*this, u.id, v.id) : INVALID;
116    }
117   
118     
119    class Node {
120      friend class FullGraphBase;
121
122    protected:
123      int id;
124      Node(int _id) { id = _id;}
125    public:
126      Node() {}
127      Node (Invalid) { id = -1; }
128      bool operator==(const Node node) const {return id == node.id;}
129      bool operator!=(const Node node) const {return id != node.id;}
130      bool operator<(const Node node) const {return id < node.id;}
131    };
132   
133
134
135    class Edge {
136      friend class FullGraphBase;
137     
138    protected:
139      int id;  // NodeNum * head + tail;
140
141      Edge(int _id) : id(_id) {}
142
143      Edge(const FullGraphBase& _graph, int tail, int head)
144        : id(_graph.NodeNum * head+tail) {}
145    public:
146      Edge() { }
147      Edge (Invalid) { id = -1; }
148      bool operator==(const Edge edge) const {return id == edge.id;}
149      bool operator!=(const Edge edge) const {return id != edge.id;}
150      bool operator<(const Edge edge) const {return id < edge.id;}
151    };
152
153    void first(Node& node) const {
154      node.id = NodeNum-1;
155    }
156
157    static void next(Node& node) {
158      --node.id;
159    }
160
161    void first(Edge& edge) const {
162      edge.id = EdgeNum-1;
163    }
164
165    static void next(Edge& edge) {
166      --edge.id;
167    }
168
169    void firstOut(Edge& edge, const Node& node) const {
170      edge.id = EdgeNum + node.id - NodeNum;
171    }
172
173    void nextOut(Edge& edge) const {
174      edge.id -= NodeNum;
175      if (edge.id < 0) edge.id = -1;
176    }
177
178    void firstIn(Edge& edge, const Node& node) const {
179      edge.id = node.id * NodeNum;
180    }
181   
182    void nextIn(Edge& edge) const {
183      ++edge.id;
184      if (edge.id % NodeNum == 0) edge.id = -1;
185    }
186
187  };
188
189
190  typedef AlterableGraphExtender<FullGraphBase> AlterableFullGraphBase;
191  typedef IterableGraphExtender<AlterableFullGraphBase> IterableFullGraphBase;
192  typedef DefaultMappableGraphExtender<IterableFullGraphBase> MappableFullGraphBase;
193
194  ///A full graph class.
195
196  ///This is a simple and fast directed full graph implementation.
197  ///It is completely static, so you can neither add nor delete either
198  ///edges or nodes.
199  ///Thus it conforms to
200  ///the \ref concept::StaticGraph "StaticGraph" concept
201  ///\sa concept::StaticGraph.
202  ///
203  ///\author Alpar Juttner
204  class FullGraph : public MappableFullGraphBase {
205  public:
206
207    FullGraph(int n) { construct(n); }
208  };
209
210
211  /// Base graph class for UndirFullGraph.
212
213  class UndirFullGraphBase {
214    int NodeNum;
215    int EdgeNum;
216  public:
217
218    typedef FullGraphBase Graph;
219
220    class Node;
221    class Edge;
222
223  public:
224
225    FullGraphBase() {}
226
227
228    ///Creates a full graph with \c n nodes.
229    void construct(int n) { NodeNum = n; EdgeNum = n * (n - 1) / 2; }
230    ///
231    //    FullGraphBase(const FullGraphBase &_g)
232    //      : NodeNum(_g.nodeNum()), EdgeNum(NodeNum*NodeNum) { }
233   
234    typedef True NodeNumTag;
235    typedef True EdgeNumTag;
236
237    ///Number of nodes.
238    int nodeNum() const { return NodeNum; }
239    ///Number of edges.
240    int edgeNum() const { return EdgeNum; }
241
242    /// Maximum node ID.
243   
244    /// Maximum node ID.
245    ///\sa id(Node)
246    int maxId(Node = INVALID) const { return NodeNum-1; }
247    /// Maximum edge ID.
248   
249    /// Maximum edge ID.
250    ///\sa id(Edge)
251    int maxId(Edge = INVALID) const { return EdgeNum-1; }
252
253    Node tail(Edge e) const {
254      /// \todo we may do it faster
255      return ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;
256    }
257
258    Node head(Edge e) const {
259      int tail = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
260      return e.id - (tail) * (tail - 1) / 2;
261    }
262
263
264    /// Node ID.
265   
266    /// The ID of a valid Node is a nonnegative integer not greater than
267    /// \ref maxNodeId(). The range of the ID's is not surely continuous
268    /// and the greatest node ID can be actually less then \ref maxNodeId().
269    ///
270    /// The ID of the \ref INVALID node is -1.
271    ///\return The ID of the node \c v.
272
273    static int id(Node v) { return v.id; }
274    /// Edge ID.
275   
276    /// The ID of a valid Edge is a nonnegative integer not greater than
277    /// \ref maxEdgeId(). The range of the ID's is not surely continuous
278    /// and the greatest edge ID can be actually less then \ref maxEdgeId().
279    ///
280    /// The ID of the \ref INVALID edge is -1.
281    ///\return The ID of the edge \c e.
282    static int id(Edge e) { return e.id; }
283
284    /// Finds an edge between two nodes.
285   
286    /// Finds an edge from node \c u to node \c v.
287    ///
288    /// If \c prev is \ref INVALID (this is the default value), then
289    /// It finds the first edge from \c u to \c v. Otherwise it looks for
290    /// the next edge from \c u to \c v after \c prev.
291    /// \return The found edge or INVALID if there is no such an edge.
292    Edge findEdge(Node u,Node v, Edge prev = INVALID)
293    {
294      return prev.id == -1 ? Edge(*this, u.id, v.id) : INVALID;
295    }
296   
297     
298    class Node {
299      friend class FullGraphBase;
300
301    protected:
302      int id;
303      Node(int _id) { id = _id;}
304    public:
305      Node() {}
306      Node (Invalid) { id = -1; }
307      bool operator==(const Node node) const {return id == node.id;}
308      bool operator!=(const Node node) const {return id != node.id;}
309      bool operator<(const Node node) const {return id < node.id;}
310    };
311   
312
313
314    class Edge {
315      friend class FullGraphBase;
316     
317    protected:
318      int id;  // NodeNum * head + tail;
319
320      Edge(int _id) : id(_id) {}
321
322      Edge(const FullGraphBase& _graph, int tail, int head)
323        : id(_graph.NodeNum * head+tail) {}
324    public:
325      Edge() { }
326      Edge (Invalid) { id = -1; }
327      bool operator==(const Edge edge) const {return id == edge.id;}
328      bool operator!=(const Edge edge) const {return id != edge.id;}
329      bool operator<(const Edge edge) const {return id < edge.id;}
330    };
331
332    void first(Node& node) const {
333      node.id = NodeNum-1;
334    }
335
336    static void next(Node& node) {
337      --node.id;
338    }
339
340    void first(Edge& edge) const {
341      edge.id = EdgeNum-1;
342    }
343
344    static void next(Edge& edge) {
345      --edge.id;
346    }
347
348    void firstOut(Edge& edge, const Node& node) const {     
349      edge.id = node.id != 0 ? node.id * (node.id - 1) / 2 : -1;
350    }
351
352    /// \todo with specialized iterators we can make faster iterating
353    void nextOut(Edge& edge) const {
354      int tail = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
355      int head = e.id - (tail) * (tail - 1) / 2;
356      ++head;
357      return head < tail ? tail * (tail - 1) / 2 + head : -1;
358    }
359
360    void firstIn(Edge& edge, const Node& node) const {
361      edge.id = node.id * (node.id + 1) / 2 - 1;
362    }
363   
364    void nextIn(Edge& edge) const {
365      int tail = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
366      int head = e.id - (tail) * (tail - 1) / 2; ++head;
367      ++tail;
368      return tail < nodeNum ? tail * (tail - 1) / 2 + head : -1;
369    }
370
371  };
372
373  /// \todo UndirFullGraph from the UndirFullGraphBase
374
375 
376
377  /// @} 
378
379} //namespace lemon
380
381
382#endif //LEMON_FULL_GRAPH_H
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