COIN-OR::LEMON - Graph Library

source: lemon-0.x/lemon/full_ugraph.h @ 2115:4cd528a30ec1

Last change on this file since 2115:4cd528a30ec1 was 2115:4cd528a30ec1, checked in by Balazs Dezso, 13 years ago

Splitted graph files

File size: 7.8 KB
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1/* -*- C++ -*-
2 *
3 * This file is a part of LEMON, a generic C++ optimization library
4 *
5 * Copyright (C) 2003-2006
6 * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
7 * (Egervary Research Group on Combinatorial Optimization, EGRES).
8 *
9 * Permission to use, modify and distribute this software is granted
10 * provided that this copyright notice appears in all copies. For
11 * precise terms see the accompanying LICENSE file.
12 *
13 * This software is provided "AS IS" with no warranty of any kind,
14 * express or implied, and with no claim as to its suitability for any
15 * purpose.
16 *
17 */
18
19#ifndef LEMON_FULL_UGRAPH_H
20#define LEMON_FULL_UGRAPH_H
21
22#include <cmath>
23
24#include <lemon/bits/base_extender.h>
25#include <lemon/bits/ugraph_extender.h>
26
27#include <lemon/bits/invalid.h>
28#include <lemon/bits/utility.h>
29
30
31///\ingroup graphs
32///\file
33///\brief FullUGraph classes.
34
35
36namespace lemon {
37
38  /// \brief Base of the FullUGrpah.
39  ///
40  /// Base of the FullUGrpah.
41  class FullUGraphBase {
42    int _nodeNum;
43    int _edgeNum;
44  public:
45
46    typedef FullUGraphBase Graph;
47
48    class Node;
49    class Edge;
50
51  public:
52
53    FullUGraphBase() {}
54
55
56    ///Creates a full graph with \c n nodes.
57    void construct(int n) { _nodeNum = n; _edgeNum = n * (n - 1) / 2; }
58
59    /// \brief Returns the node with the given index.
60    ///
61    /// Returns the node with the given index. Because it is a
62    /// static size graph the node's of the graph can be indiced
63    /// by the range from 0 to \e nodeNum()-1 and the index of
64    /// the node can accessed by the \e index() member.
65    Node operator()(int index) const { return Node(index); }
66
67    /// \brief Returns the index of the node.
68    ///
69    /// Returns the index of the node. Because it is a
70    /// static size graph the node's of the graph can be indiced
71    /// by the range from 0 to \e nodeNum()-1 and the index of
72    /// the node can accessed by the \e index() member.
73    int index(const Node& node) const { return node.id; }
74
75    typedef True NodeNumTag;
76    typedef True EdgeNumTag;
77
78    ///Number of nodes.
79    int nodeNum() const { return _nodeNum; }
80    ///Number of edges.
81    int edgeNum() const { return _edgeNum; }
82
83    /// Maximum node ID.
84   
85    /// Maximum node ID.
86    ///\sa id(Node)
87    int maxNodeId() const { return _nodeNum-1; }
88    /// Maximum edge ID.
89   
90    /// Maximum edge ID.
91    ///\sa id(Edge)
92    int maxEdgeId() const { return _edgeNum-1; }
93
94    /// \brief Returns the node from its \c id.
95    ///
96    /// Returns the node from its \c id. If there is not node
97    /// with the given id the effect of the function is undefinied.
98    static Node nodeFromId(int id) { return Node(id);}
99
100    /// \brief Returns the edge from its \c id.
101    ///
102    /// Returns the edge from its \c id. If there is not edge
103    /// with the given id the effect of the function is undefinied.
104    static Edge edgeFromId(int id) { return Edge(id);}
105
106    Node source(Edge e) const {
107      /// \todo we may do it faster
108      return Node(((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2);
109    }
110
111    Node target(Edge e) const {
112      int source = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;
113      return Node(e.id - (source) * (source - 1) / 2);
114    }
115
116
117    /// \brief Node ID.
118    ///
119    /// The ID of a valid Node is a nonnegative integer not greater than
120    /// \ref maxNodeId(). The range of the ID's is not surely continuous
121    /// and the greatest node ID can be actually less then \ref maxNodeId().
122    ///
123    /// The ID of the \ref INVALID node is -1.
124    /// \return The ID of the node \c v.
125
126    static int id(Node v) { return v.id; }
127
128    /// \brief Edge ID.
129    ///
130    /// The ID of a valid Edge is a nonnegative integer not greater than
131    /// \ref maxEdgeId(). The range of the ID's is not surely continuous
132    /// and the greatest edge ID can be actually less then \ref maxEdgeId().
133    ///
134    /// The ID of the \ref INVALID edge is -1.
135    ///\return The ID of the edge \c e.
136    static int id(Edge e) { return e.id; }
137
138    /// \brief Finds an edge between two nodes.
139    ///
140    /// Finds an edge from node \c u to node \c v.
141    ///
142    /// If \c prev is \ref INVALID (this is the default value), then
143    /// It finds the first edge from \c u to \c v. Otherwise it looks for
144    /// the next edge from \c u to \c v after \c prev.
145    /// \return The found edge or INVALID if there is no such an edge.
146    Edge findEdge(Node u, Node v, Edge prev = INVALID) const {
147      if (prev.id != -1 || u.id <= v.id) return Edge(-1);
148      return Edge(u.id * (u.id - 1) / 2 + v.id);
149    }
150
151    typedef True FindEdgeTag;
152   
153     
154    class Node {
155      friend class FullUGraphBase;
156
157    protected:
158      int id;
159      Node(int _id) { id = _id;}
160    public:
161      Node() {}
162      Node (Invalid) { id = -1; }
163      bool operator==(const Node node) const {return id == node.id;}
164      bool operator!=(const Node node) const {return id != node.id;}
165      bool operator<(const Node node) const {return id < node.id;}
166    };
167   
168
169
170    class Edge {
171      friend class FullUGraphBase;
172     
173    protected:
174      int id;  // _nodeNum * target + source;
175
176      Edge(int _id) : id(_id) {}
177
178    public:
179      Edge() { }
180      Edge (Invalid) { id = -1; }
181      bool operator==(const Edge edge) const {return id == edge.id;}
182      bool operator!=(const Edge edge) const {return id != edge.id;}
183      bool operator<(const Edge edge) const {return id < edge.id;}
184    };
185
186    void first(Node& node) const {
187      node.id = _nodeNum - 1;
188    }
189
190    static void next(Node& node) {
191      --node.id;
192    }
193
194    void first(Edge& edge) const {
195      edge.id = _edgeNum - 1;
196    }
197
198    static void next(Edge& edge) {
199      --edge.id;
200    }
201
202    void firstOut(Edge& edge, const Node& node) const {     
203      int src = node.id;
204      int trg = 0;
205      edge.id = (trg < src ? src * (src - 1) / 2 + trg : -1);
206    }
207
208    /// \todo with specialized iterators we can make faster iterating
209    void nextOut(Edge& edge) const {
210      int src = source(edge).id;
211      int trg = target(edge).id;
212      ++trg;
213      edge.id = (trg < src ? src * (src - 1) / 2 + trg : -1);
214    }
215
216    void firstIn(Edge& edge, const Node& node) const {
217      int src = node.id + 1;
218      int trg = node.id;
219      edge.id = (src < _nodeNum ? src * (src - 1) / 2 + trg : -1);
220    }
221   
222    void nextIn(Edge& edge) const {
223      int src = source(edge).id;
224      int trg = target(edge).id;
225      ++src;
226      edge.id = (src < _nodeNum ? src * (src - 1) / 2 + trg : -1);
227    }
228
229  };
230
231  typedef UGraphExtender<UndirGraphExtender<FullUGraphBase> >
232  ExtendedFullUGraphBase;
233
234  /// \ingroup graphs
235  ///
236  /// \brief An undirected full graph class.
237  ///
238  /// This is a simple and fast undirected full graph implementation.
239  /// It is completely static, so you can neither add nor delete either
240  /// edges or nodes.
241  ///
242  /// The main difference beetween the \e FullGraph and \e FullUGraph class
243  /// is that this class conforms to the undirected graph concept and
244  /// it does not contain the loop edges.
245  ///
246  /// \sa FullUGraphBase
247  /// \sa FullGraph
248  ///
249  /// \author Balazs Dezso
250  class FullUGraph : public ExtendedFullUGraphBase {
251  public:
252
253    typedef ExtendedFullUGraphBase Parent;
254
255    /// \brief Constructor
256    FullUGraph() { construct(0); }
257
258    /// \brief Constructor
259    FullUGraph(int n) { construct(n); }
260
261    /// \brief Resize the graph
262    ///
263    /// Resize the graph. The function will fully destroy and build the graph.
264    /// This cause that the maps of the graph will reallocated
265    /// automatically and the previous values will be lost.
266    void resize(int n) {
267      Parent::getNotifier(Edge()).clear();
268      Parent::getNotifier(UEdge()).clear();
269      Parent::getNotifier(Node()).clear();
270      construct(n);
271      Parent::getNotifier(Node()).build();
272      Parent::getNotifier(UEdge()).build();
273      Parent::getNotifier(Edge()).build();
274    }
275  };
276
277} //namespace lemon
278
279
280#endif //LEMON_FULL_GRAPH_H
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