1 | /* -*- C++ -*- |
---|
2 | * src/lemon/graph_utils.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_GRAPH_UTILS_H |
---|
18 | #define LEMON_GRAPH_UTILS_H |
---|
19 | |
---|
20 | #include <iterator> |
---|
21 | |
---|
22 | #include <lemon/invalid.h> |
---|
23 | #include <lemon/utility.h> |
---|
24 | |
---|
25 | ///\ingroup gutils |
---|
26 | ///\file |
---|
27 | ///\brief Graph utilities. |
---|
28 | /// |
---|
29 | ///\todo Please |
---|
30 | ///revise the documentation. |
---|
31 | /// |
---|
32 | |
---|
33 | |
---|
34 | namespace lemon { |
---|
35 | |
---|
36 | /// \addtogroup gutils |
---|
37 | /// @{ |
---|
38 | |
---|
39 | /// \brief Function to count the items in the graph. |
---|
40 | /// |
---|
41 | /// This function counts the items in the graph. |
---|
42 | /// The complexity of the function is O(n) because |
---|
43 | /// it iterates on all of the items. |
---|
44 | |
---|
45 | template <typename Graph, typename ItemIt> |
---|
46 | inline int countItems(const Graph& g) { |
---|
47 | int num = 0; |
---|
48 | for (ItemIt it(g); it != INVALID; ++it) { |
---|
49 | ++num; |
---|
50 | } |
---|
51 | return num; |
---|
52 | } |
---|
53 | |
---|
54 | // Node counting: |
---|
55 | |
---|
56 | template <typename Graph> |
---|
57 | inline |
---|
58 | typename enable_if<typename Graph::NodeNumTag, int>::type |
---|
59 | _countNodes(const Graph &g) { |
---|
60 | return g.nodeNum(); |
---|
61 | } |
---|
62 | |
---|
63 | template <typename Graph> |
---|
64 | inline int _countNodes(Wrap<Graph> w) { |
---|
65 | return countItems<Graph, typename Graph::NodeIt>(w.value); |
---|
66 | } |
---|
67 | |
---|
68 | /// \brief Function to count the nodes in the graph. |
---|
69 | /// |
---|
70 | /// This function counts the nodes in the graph. |
---|
71 | /// The complexity of the function is O(n) but for some |
---|
72 | /// graph structure it is specialized to run in O(1). |
---|
73 | /// |
---|
74 | /// \todo refer how to specialize it |
---|
75 | |
---|
76 | template <typename Graph> |
---|
77 | inline int countNodes(const Graph& g) { |
---|
78 | return _countNodes<Graph>(g); |
---|
79 | } |
---|
80 | |
---|
81 | // Edge counting: |
---|
82 | |
---|
83 | template <typename Graph> |
---|
84 | inline |
---|
85 | typename enable_if<typename Graph::EdgeNumTag, int>::type |
---|
86 | _countEdges(const Graph &g) { |
---|
87 | return g.edgeNum(); |
---|
88 | } |
---|
89 | |
---|
90 | template <typename Graph> |
---|
91 | inline int _countEdges(Wrap<Graph> w) { |
---|
92 | return countItems<Graph, typename Graph::EdgeIt>(w.value); |
---|
93 | } |
---|
94 | |
---|
95 | /// \brief Function to count the edges in the graph. |
---|
96 | /// |
---|
97 | /// This function counts the edges in the graph. |
---|
98 | /// The complexity of the function is O(e) but for some |
---|
99 | /// graph structure it is specialized to run in O(1). |
---|
100 | |
---|
101 | template <typename Graph> |
---|
102 | inline int countEdges(const Graph& g) { |
---|
103 | return _countEdges<Graph>(g); |
---|
104 | } |
---|
105 | |
---|
106 | // Undirected edge counting: |
---|
107 | |
---|
108 | template <typename Graph> |
---|
109 | inline |
---|
110 | typename enable_if<typename Graph::EdgeNumTag, int>::type |
---|
111 | _countUndirEdges(const Graph &g) { |
---|
112 | return g.undirEdgeNum(); |
---|
113 | } |
---|
114 | |
---|
115 | template <typename Graph> |
---|
116 | inline int _countUndirEdges(Wrap<Graph> w) { |
---|
117 | return countItems<Graph, typename Graph::UndirEdgeIt>(w.value); |
---|
118 | } |
---|
119 | |
---|
120 | /// \brief Function to count the edges in the graph. |
---|
121 | /// |
---|
122 | /// This function counts the edges in the graph. |
---|
123 | /// The complexity of the function is O(e) but for some |
---|
124 | /// graph structure it is specialized to run in O(1). |
---|
125 | |
---|
126 | template <typename Graph> |
---|
127 | inline int countUndirEdges(const Graph& g) { |
---|
128 | return _countUndirEdges<Graph>(g); |
---|
129 | } |
---|
130 | |
---|
131 | |
---|
132 | |
---|
133 | template <typename Graph, typename DegIt> |
---|
134 | inline int countNodeDegree(const Graph& _g, const typename Graph::Node& _n) { |
---|
135 | int num = 0; |
---|
136 | for (DegIt it(_g, _n); it != INVALID; ++it) { |
---|
137 | ++num; |
---|
138 | } |
---|
139 | return num; |
---|
140 | } |
---|
141 | |
---|
142 | /// Finds an edge between two nodes of a graph. |
---|
143 | |
---|
144 | /// Finds an edge from node \c u to node \c v in graph \c g. |
---|
145 | /// |
---|
146 | /// If \c prev is \ref INVALID (this is the default value), then |
---|
147 | /// it finds the first edge from \c u to \c v. Otherwise it looks for |
---|
148 | /// the next edge from \c u to \c v after \c prev. |
---|
149 | /// \return The found edge or \ref INVALID if there is no such an edge. |
---|
150 | /// |
---|
151 | /// Thus you can iterate through each edge from \c u to \c v as it follows. |
---|
152 | /// \code |
---|
153 | /// for(Edge e=findEdge(g,u,v);e!=INVALID;e=findEdge(g,u,v,e)) { |
---|
154 | /// ... |
---|
155 | /// } |
---|
156 | /// \endcode |
---|
157 | /// \todo We may want to use the \ref concept::GraphBase "GraphBase" |
---|
158 | /// interface here... |
---|
159 | /// \bug Untested ... |
---|
160 | template <typename Graph> |
---|
161 | typename Graph::Edge findEdge(const Graph &g, |
---|
162 | typename Graph::Node u, typename Graph::Node v, |
---|
163 | typename Graph::Edge prev = INVALID) |
---|
164 | { |
---|
165 | typename Graph::OutEdgeIt e(g,prev); |
---|
166 | // if(prev==INVALID) g.first(e,u); |
---|
167 | if(prev==INVALID) e=typename Graph::OutEdgeIt(g,u); |
---|
168 | else ++e; |
---|
169 | while(e!=INVALID && g.target(e)!=v) ++e; |
---|
170 | return e; |
---|
171 | } |
---|
172 | |
---|
173 | ///\e |
---|
174 | |
---|
175 | ///\todo Please document. |
---|
176 | /// |
---|
177 | template <typename Graph> |
---|
178 | inline int countOutEdges(const Graph& _g, const typename Graph::Node& _n) { |
---|
179 | return countNodeDegree<Graph, typename Graph::OutEdgeIt>(_g, _n); |
---|
180 | } |
---|
181 | |
---|
182 | ///\e |
---|
183 | |
---|
184 | ///\todo Please document. |
---|
185 | /// |
---|
186 | template <typename Graph> |
---|
187 | inline int countInEdges(const Graph& _g, const typename Graph::Node& _n) { |
---|
188 | return countNodeDegree<Graph, typename Graph::InEdgeIt>(_g, _n); |
---|
189 | } |
---|
190 | |
---|
191 | // graph copy |
---|
192 | |
---|
193 | template < |
---|
194 | typename DestinationGraph, |
---|
195 | typename SourceGraph, |
---|
196 | typename NodeBijection> |
---|
197 | void copyNodes(DestinationGraph& _d, const SourceGraph& _s, |
---|
198 | NodeBijection& _nb) { |
---|
199 | for (typename SourceGraph::NodeIt it(_s); it != INVALID; ++it) { |
---|
200 | _nb[it] = _d.addNode(); |
---|
201 | } |
---|
202 | } |
---|
203 | |
---|
204 | template < |
---|
205 | typename DestinationGraph, |
---|
206 | typename SourceGraph, |
---|
207 | typename NodeBijection, |
---|
208 | typename EdgeBijection> |
---|
209 | void copyEdges(DestinationGraph& _d, const SourceGraph& _s, |
---|
210 | const NodeBijection& _nb, EdgeBijection& _eb) { |
---|
211 | for (typename SourceGraph::EdgeIt it(_s); it != INVALID; ++it) { |
---|
212 | _eb[it] = _d.addEdge(_nb[_s.source(it)], _nb[_s.target(it)]); |
---|
213 | } |
---|
214 | } |
---|
215 | |
---|
216 | template < |
---|
217 | typename DestinationGraph, |
---|
218 | typename SourceGraph, |
---|
219 | typename NodeBijection, |
---|
220 | typename EdgeBijection> |
---|
221 | void copyGraph(DestinationGraph& _d, const SourceGraph& _s, |
---|
222 | NodeBijection& _nb, EdgeBijection& _eb) { |
---|
223 | nodeCopy(_d, _s, _nb); |
---|
224 | edgeCopy(_d, _s, _nb, _eb); |
---|
225 | } |
---|
226 | |
---|
227 | template < |
---|
228 | typename _DestinationGraph, |
---|
229 | typename _SourceGraph, |
---|
230 | typename _NodeBijection |
---|
231 | =typename _SourceGraph::template NodeMap<typename _DestinationGraph::Node>, |
---|
232 | typename _EdgeBijection |
---|
233 | =typename _SourceGraph::template EdgeMap<typename _DestinationGraph::Edge> |
---|
234 | > |
---|
235 | class GraphCopy { |
---|
236 | public: |
---|
237 | |
---|
238 | typedef _DestinationGraph DestinationGraph; |
---|
239 | typedef _SourceGraph SourceGraph; |
---|
240 | |
---|
241 | typedef _NodeBijection NodeBijection; |
---|
242 | typedef _EdgeBijection EdgeBijection; |
---|
243 | |
---|
244 | protected: |
---|
245 | |
---|
246 | NodeBijection node_bijection; |
---|
247 | EdgeBijection edge_bijection; |
---|
248 | |
---|
249 | public: |
---|
250 | |
---|
251 | GraphCopy(DestinationGraph& _d, const SourceGraph& _s) { |
---|
252 | copyGraph(_d, _s, node_bijection, edge_bijection); |
---|
253 | } |
---|
254 | |
---|
255 | const NodeBijection& getNodeBijection() const { |
---|
256 | return node_bijection; |
---|
257 | } |
---|
258 | |
---|
259 | const EdgeBijection& getEdgeBijection() const { |
---|
260 | return edge_bijection; |
---|
261 | } |
---|
262 | |
---|
263 | }; |
---|
264 | |
---|
265 | /// @} |
---|
266 | |
---|
267 | } //END OF NAMESPACE LEMON |
---|
268 | |
---|
269 | #endif |
---|