1 //
2 //=======================================================================
3 // Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
4 // Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
5 //
6 // Distributed under the Boost Software License, Version 1.0. (See
7 // accompanying file LICENSE_1_0.txt or copy at
8 // http://www.boost.org/LICENSE_1_0.txt)
9 //=======================================================================
10 //
11 #ifndef BOOST_GRAPH_UTILITY_HPP
12 #define BOOST_GRAPH_UTILITY_HPP
13 
14 #include <stdlib.h>
15 #include <iostream>
16 #include <algorithm>
17 #include <assert.h>
18 #include <boost/config.hpp>
19 #include <boost/tuple/tuple.hpp>
20 
21 #include <boost/graph/graph_traits.hpp>
22 #include <boost/graph/properties.hpp>
23 #include <boost/pending/container_traits.hpp>
24 #include <boost/graph/depth_first_search.hpp>
25 // iota moved to detail/algorithm.hpp
26 #include <boost/detail/algorithm.hpp>
27 
28 namespace boost
29 {
30 
31 // Provide an undirected graph interface alternative to the
32 // the source() and target() edge functions.
33 template < class UndirectedGraph >
34 inline std::pair< typename graph_traits< UndirectedGraph >::vertex_descriptor,
35     typename graph_traits< UndirectedGraph >::vertex_descriptor >
incident(typename graph_traits<UndirectedGraph>::edge_descriptor e,UndirectedGraph & g)36 incident(typename graph_traits< UndirectedGraph >::edge_descriptor e,
37     UndirectedGraph& g)
38 {
39     return std::make_pair(source(e, g), target(e, g));
40 }
41 
42 // Provide an undirected graph interface alternative
43 // to the out_edges() function.
44 template < class Graph >
45 inline std::pair< typename graph_traits< Graph >::out_edge_iterator,
46     typename graph_traits< Graph >::out_edge_iterator >
incident_edges(typename graph_traits<Graph>::vertex_descriptor u,Graph & g)47 incident_edges(typename graph_traits< Graph >::vertex_descriptor u, Graph& g)
48 {
49     return out_edges(u, g);
50 }
51 
52 template < class Graph >
opposite(typename graph_traits<Graph>::edge_descriptor e,typename graph_traits<Graph>::vertex_descriptor v,const Graph & g)53 inline typename graph_traits< Graph >::vertex_descriptor opposite(
54     typename graph_traits< Graph >::edge_descriptor e,
55     typename graph_traits< Graph >::vertex_descriptor v, const Graph& g)
56 {
57     typedef typename graph_traits< Graph >::vertex_descriptor vertex_descriptor;
58     if (v == source(e, g))
59         return target(e, g);
60     else if (v == target(e, g))
61         return source(e, g);
62     else
63         return vertex_descriptor();
64 }
65 
66 //===========================================================================
67 // Some handy predicates
68 
69 template < typename Vertex, typename Graph > struct incident_from_predicate
70 {
incident_from_predicateboost::incident_from_predicate71     incident_from_predicate(Vertex u, const Graph& g) : m_u(u), m_g(g) {}
operator ()boost::incident_from_predicate72     template < class Edge > bool operator()(const Edge& e) const
73     {
74         return source(e, m_g) == m_u;
75     }
76     Vertex m_u;
77     const Graph& m_g;
78 };
79 template < typename Vertex, typename Graph >
incident_from(Vertex u,const Graph & g)80 inline incident_from_predicate< Vertex, Graph > incident_from(
81     Vertex u, const Graph& g)
82 {
83     return incident_from_predicate< Vertex, Graph >(u, g);
84 }
85 
86 template < typename Vertex, typename Graph > struct incident_to_predicate
87 {
incident_to_predicateboost::incident_to_predicate88     incident_to_predicate(Vertex u, const Graph& g) : m_u(u), m_g(g) {}
operator ()boost::incident_to_predicate89     template < class Edge > bool operator()(const Edge& e) const
90     {
91         return target(e, m_g) == m_u;
92     }
93     Vertex m_u;
94     const Graph& m_g;
95 };
96 template < typename Vertex, typename Graph >
incident_to(Vertex u,const Graph & g)97 inline incident_to_predicate< Vertex, Graph > incident_to(
98     Vertex u, const Graph& g)
99 {
100     return incident_to_predicate< Vertex, Graph >(u, g);
101 }
102 
103 template < typename Vertex, typename Graph > struct incident_on_predicate
104 {
incident_on_predicateboost::incident_on_predicate105     incident_on_predicate(Vertex u, const Graph& g) : m_u(u), m_g(g) {}
operator ()boost::incident_on_predicate106     template < class Edge > bool operator()(const Edge& e) const
107     {
108         return source(e, m_g) == m_u || target(e, m_g) == m_u;
109     }
110     Vertex m_u;
111     const Graph& m_g;
112 };
113 template < typename Vertex, typename Graph >
incident_on(Vertex u,const Graph & g)114 inline incident_on_predicate< Vertex, Graph > incident_on(
115     Vertex u, const Graph& g)
116 {
117     return incident_on_predicate< Vertex, Graph >(u, g);
118 }
119 
120 template < typename Vertex, typename Graph > struct connects_predicate
121 {
connects_predicateboost::connects_predicate122     connects_predicate(Vertex u, Vertex v, const Graph& g)
123     : m_u(u), m_v(v), m_g(g)
124     {
125     }
operator ()boost::connects_predicate126     template < class Edge > bool operator()(const Edge& e) const
127     {
128         if (is_directed(m_g))
129             return source(e, m_g) == m_u && target(e, m_g) == m_v;
130         else
131             return (source(e, m_g) == m_u && target(e, m_g) == m_v)
132                 || (source(e, m_g) == m_v && target(e, m_g) == m_u);
133     }
134     Vertex m_u, m_v;
135     const Graph& m_g;
136 };
137 template < typename Vertex, typename Graph >
connects(Vertex u,Vertex v,const Graph & g)138 inline connects_predicate< Vertex, Graph > connects(
139     Vertex u, Vertex v, const Graph& g)
140 {
141     return connects_predicate< Vertex, Graph >(u, v, g);
142 }
143 
144 // Need to convert all of these printing functions to take an ostream object
145 // -JGS
146 
147 template < class IncidenceGraph, class Name >
print_in_edges(const IncidenceGraph & G,Name name,std::ostream & os=std::cout)148 void print_in_edges(
149     const IncidenceGraph& G, Name name, std::ostream& os = std::cout)
150 {
151     typename graph_traits< IncidenceGraph >::vertex_iterator ui, ui_end;
152     for (boost::tie(ui, ui_end) = vertices(G); ui != ui_end; ++ui)
153     {
154         os << get(name, *ui) << " <-- ";
155         typename graph_traits< IncidenceGraph >::in_edge_iterator ei, ei_end;
156         for (boost::tie(ei, ei_end) = in_edges(*ui, G); ei != ei_end; ++ei)
157             os << get(name, source(*ei, G)) << " ";
158         os << '\n';
159     }
160 }
161 
162 template < class IncidenceGraph, class Name >
print_graph_dispatch(const IncidenceGraph & G,Name name,directed_tag,std::ostream & os=std::cout)163 void print_graph_dispatch(const IncidenceGraph& G, Name name, directed_tag,
164     std::ostream& os = std::cout)
165 {
166     typename graph_traits< IncidenceGraph >::vertex_iterator ui, ui_end;
167     for (boost::tie(ui, ui_end) = vertices(G); ui != ui_end; ++ui)
168     {
169         os << get(name, *ui) << " --> ";
170         typename graph_traits< IncidenceGraph >::out_edge_iterator ei, ei_end;
171         for (boost::tie(ei, ei_end) = out_edges(*ui, G); ei != ei_end; ++ei)
172             os << get(name, target(*ei, G)) << " ";
173         os << '\n';
174     }
175 }
176 template < class IncidenceGraph, class Name >
print_graph_dispatch(const IncidenceGraph & G,Name name,undirected_tag,std::ostream & os=std::cout)177 void print_graph_dispatch(const IncidenceGraph& G, Name name, undirected_tag,
178     std::ostream& os = std::cout)
179 {
180     typename graph_traits< IncidenceGraph >::vertex_iterator ui, ui_end;
181     for (boost::tie(ui, ui_end) = vertices(G); ui != ui_end; ++ui)
182     {
183         os << get(name, *ui) << " <--> ";
184         typename graph_traits< IncidenceGraph >::out_edge_iterator ei, ei_end;
185         for (boost::tie(ei, ei_end) = out_edges(*ui, G); ei != ei_end; ++ei)
186             os << get(name, target(*ei, G)) << " ";
187         os << '\n';
188     }
189 }
190 template < class IncidenceGraph, class Name >
print_graph(const IncidenceGraph & G,Name name,std::ostream & os=std::cout)191 void print_graph(
192     const IncidenceGraph& G, Name name, std::ostream& os = std::cout)
193 {
194     typedef typename graph_traits< IncidenceGraph >::directed_category Cat;
195     print_graph_dispatch(G, name, Cat(), os);
196 }
197 template < class IncidenceGraph >
print_graph(const IncidenceGraph & G,std::ostream & os=std::cout)198 void print_graph(const IncidenceGraph& G, std::ostream& os = std::cout)
199 {
200     print_graph(G, get(vertex_index, G), os);
201 }
202 
203 template < class EdgeListGraph, class Name >
print_edges(const EdgeListGraph & G,Name name,std::ostream & os=std::cout)204 void print_edges(
205     const EdgeListGraph& G, Name name, std::ostream& os = std::cout)
206 {
207     typename graph_traits< EdgeListGraph >::edge_iterator ei, ei_end;
208     for (boost::tie(ei, ei_end) = edges(G); ei != ei_end; ++ei)
209         os << "(" << get(name, source(*ei, G)) << ","
210            << get(name, target(*ei, G)) << ") ";
211     os << '\n';
212 }
213 
214 template < class EdgeListGraph, class VertexName, class EdgeName >
print_edges2(const EdgeListGraph & G,VertexName vname,EdgeName ename,std::ostream & os=std::cout)215 void print_edges2(const EdgeListGraph& G, VertexName vname, EdgeName ename,
216     std::ostream& os = std::cout)
217 {
218     typename graph_traits< EdgeListGraph >::edge_iterator ei, ei_end;
219     for (boost::tie(ei, ei_end) = edges(G); ei != ei_end; ++ei)
220         os << get(ename, *ei) << "(" << get(vname, source(*ei, G)) << ","
221            << get(vname, target(*ei, G)) << ") ";
222     os << '\n';
223 }
224 
225 template < class VertexListGraph, class Name >
print_vertices(const VertexListGraph & G,Name name,std::ostream & os=std::cout)226 void print_vertices(
227     const VertexListGraph& G, Name name, std::ostream& os = std::cout)
228 {
229     typename graph_traits< VertexListGraph >::vertex_iterator vi, vi_end;
230     for (boost::tie(vi, vi_end) = vertices(G); vi != vi_end; ++vi)
231         os << get(name, *vi) << " ";
232     os << '\n';
233 }
234 
235 template < class Graph, class Vertex >
is_adj_dispatch(Graph & g,Vertex a,Vertex b,bidirectional_tag)236 bool is_adj_dispatch(Graph& g, Vertex a, Vertex b, bidirectional_tag)
237 {
238     typename graph_traits< Graph >::adjacency_iterator vi, viend, adj_found;
239     boost::tie(vi, viend) = adjacent_vertices(a, g);
240     adj_found = std::find(vi, viend, b);
241     if (adj_found == viend)
242         return false;
243 
244     typename graph_traits< Graph >::out_edge_iterator oi, oiend, out_found;
245     boost::tie(oi, oiend) = out_edges(a, g);
246     out_found = std::find_if(oi, oiend, incident_to(b, g));
247     if (out_found == oiend)
248         return false;
249 
250     typename graph_traits< Graph >::in_edge_iterator ii, iiend, in_found;
251     boost::tie(ii, iiend) = in_edges(b, g);
252     in_found = std::find_if(ii, iiend, incident_from(a, g));
253     if (in_found == iiend)
254         return false;
255 
256     return true;
257 }
258 template < class Graph, class Vertex >
is_adj_dispatch(Graph & g,Vertex a,Vertex b,directed_tag)259 bool is_adj_dispatch(Graph& g, Vertex a, Vertex b, directed_tag)
260 {
261     typename graph_traits< Graph >::adjacency_iterator vi, viend, found;
262     boost::tie(vi, viend) = adjacent_vertices(a, g);
263     found = std::find(vi, viend, b);
264     if (found == viend)
265         return false;
266 
267     typename graph_traits< Graph >::out_edge_iterator oi, oiend, out_found;
268     boost::tie(oi, oiend) = out_edges(a, g);
269 
270     out_found = std::find_if(oi, oiend, incident_to(b, g));
271     if (out_found == oiend)
272         return false;
273     return true;
274 }
275 template < class Graph, class Vertex >
is_adj_dispatch(Graph & g,Vertex a,Vertex b,undirected_tag)276 bool is_adj_dispatch(Graph& g, Vertex a, Vertex b, undirected_tag)
277 {
278     return is_adj_dispatch(g, a, b, directed_tag());
279 }
280 
281 template < class Graph, class Vertex >
is_adjacent(Graph & g,Vertex a,Vertex b)282 bool is_adjacent(Graph& g, Vertex a, Vertex b)
283 {
284     typedef typename graph_traits< Graph >::directed_category Cat;
285     return is_adj_dispatch(g, a, b, Cat());
286 }
287 
in_edge_set(Graph & g,Edge e)288 template < class Graph, class Edge > bool in_edge_set(Graph& g, Edge e)
289 {
290     typename Graph::edge_iterator ei, ei_end, found;
291     boost::tie(ei, ei_end) = edges(g);
292     found = std::find(ei, ei_end, e);
293     return found != ei_end;
294 }
295 
in_vertex_set(Graph & g,Vertex v)296 template < class Graph, class Vertex > bool in_vertex_set(Graph& g, Vertex v)
297 {
298     typename Graph::vertex_iterator vi, vi_end, found;
299     boost::tie(vi, vi_end) = vertices(g);
300     found = std::find(vi, vi_end, v);
301     return found != vi_end;
302 }
303 
304 template < class Graph, class Vertex >
in_edge_set(Graph & g,Vertex u,Vertex v)305 bool in_edge_set(Graph& g, Vertex u, Vertex v)
306 {
307     typename Graph::edge_iterator ei, ei_end;
308     for (boost::tie(ei, ei_end) = edges(g); ei != ei_end; ++ei)
309         if (source(*ei, g) == u && target(*ei, g) == v)
310             return true;
311     return false;
312 }
313 
314 // is x a descendant of y?
315 template < typename ParentMap >
is_descendant(typename property_traits<ParentMap>::value_type x,typename property_traits<ParentMap>::value_type y,ParentMap parent)316 inline bool is_descendant(typename property_traits< ParentMap >::value_type x,
317     typename property_traits< ParentMap >::value_type y, ParentMap parent)
318 {
319     if (get(parent, x) == x) // x is the root of the tree
320         return false;
321     else if (get(parent, x) == y)
322         return true;
323     else
324         return is_descendant(get(parent, x), y, parent);
325 }
326 
327 // is y reachable from x?
328 template < typename IncidenceGraph, typename VertexColorMap >
is_reachable(typename graph_traits<IncidenceGraph>::vertex_descriptor x,typename graph_traits<IncidenceGraph>::vertex_descriptor y,const IncidenceGraph & g,VertexColorMap color)329 inline bool is_reachable(
330     typename graph_traits< IncidenceGraph >::vertex_descriptor x,
331     typename graph_traits< IncidenceGraph >::vertex_descriptor y,
332     const IncidenceGraph& g,
333     VertexColorMap color) // should start out white for every vertex
334 {
335     typedef typename property_traits< VertexColorMap >::value_type ColorValue;
336     dfs_visitor<> vis;
337     depth_first_visit(g, x, vis, color);
338     return get(color, y) != color_traits< ColorValue >::white();
339 }
340 
341 // Is the undirected graph connected?
342 // Is the directed graph strongly connected?
343 template < typename VertexListGraph, typename VertexColorMap >
is_connected(const VertexListGraph & g,VertexColorMap color)344 inline bool is_connected(const VertexListGraph& g, VertexColorMap color)
345 {
346     typedef typename property_traits< VertexColorMap >::value_type ColorValue;
347     typedef color_traits< ColorValue > Color;
348     typename graph_traits< VertexListGraph >::vertex_iterator ui, ui_end, vi,
349         vi_end, ci, ci_end;
350     for (boost::tie(ui, ui_end) = vertices(g); ui != ui_end; ++ui)
351         for (boost::tie(vi, vi_end) = vertices(g); vi != vi_end; ++vi)
352             if (*ui != *vi)
353             {
354                 for (boost::tie(ci, ci_end) = vertices(g); ci != ci_end; ++ci)
355                     put(color, *ci, Color::white());
356                 if (!is_reachable(*ui, *vi, g, color))
357                     return false;
358             }
359     return true;
360 }
361 
362 template < typename Graph >
is_self_loop(typename graph_traits<Graph>::edge_descriptor e,const Graph & g)363 bool is_self_loop(
364     typename graph_traits< Graph >::edge_descriptor e, const Graph& g)
365 {
366     return source(e, g) == target(e, g);
367 }
368 
369 template < class T1, class T2 >
make_list(const T1 & t1,const T2 & t2)370 std::pair< T1, T2 > make_list(const T1& t1, const T2& t2)
371 {
372     return std::make_pair(t1, t2);
373 }
374 
375 template < class T1, class T2, class T3 >
make_list(const T1 & t1,const T2 & t2,const T3 & t3)376 std::pair< T1, std::pair< T2, T3 > > make_list(
377     const T1& t1, const T2& t2, const T3& t3)
378 {
379     return std::make_pair(t1, std::make_pair(t2, t3));
380 }
381 
382 template < class T1, class T2, class T3, class T4 >
make_list(const T1 & t1,const T2 & t2,const T3 & t3,const T4 & t4)383 std::pair< T1, std::pair< T2, std::pair< T3, T4 > > > make_list(
384     const T1& t1, const T2& t2, const T3& t3, const T4& t4)
385 {
386     return std::make_pair(t1, std::make_pair(t2, std::make_pair(t3, t4)));
387 }
388 
389 template < class T1, class T2, class T3, class T4, class T5 >
390 std::pair< T1, std::pair< T2, std::pair< T3, std::pair< T4, T5 > > > >
make_list(const T1 & t1,const T2 & t2,const T3 & t3,const T4 & t4,const T5 & t5)391 make_list(const T1& t1, const T2& t2, const T3& t3, const T4& t4, const T5& t5)
392 {
393     return std::make_pair(
394         t1, std::make_pair(t2, std::make_pair(t3, std::make_pair(t4, t5))));
395 }
396 
397 namespace graph
398 {
399 
400     // Functor for remove_parallel_edges: edge property of the removed edge is
401     // added to the remaining
402     template < typename EdgeProperty > struct add_removed_edge_property
403     {
add_removed_edge_propertyboost::graph::add_removed_edge_property404         add_removed_edge_property(EdgeProperty ep) : ep(ep) {}
405 
operator ()boost::graph::add_removed_edge_property406         template < typename Edge > void operator()(Edge stay, Edge away)
407         {
408             put(ep, stay, get(ep, stay) + get(ep, away));
409         }
410         EdgeProperty ep;
411     };
412 
413     // Same as above: edge property is capacity here
414     template < typename Graph >
415     struct add_removed_edge_capacity
416     : add_removed_edge_property<
417           typename property_map< Graph, edge_capacity_t >::type >
418     {
419         typedef add_removed_edge_property<
420             typename property_map< Graph, edge_capacity_t >::type >
421             base;
add_removed_edge_capacityboost::graph::add_removed_edge_capacity422         add_removed_edge_capacity(Graph& g) : base(get(edge_capacity, g)) {}
423     };
424 
has_no_vertices(const Graph & g)425     template < typename Graph > bool has_no_vertices(const Graph& g)
426     {
427         typedef typename boost::graph_traits< Graph >::vertex_iterator vi;
428         std::pair< vi, vi > p = vertices(g);
429         return (p.first == p.second);
430     }
431 
has_no_edges(const Graph & g)432     template < typename Graph > bool has_no_edges(const Graph& g)
433     {
434         typedef typename boost::graph_traits< Graph >::edge_iterator ei;
435         std::pair< ei, ei > p = edges(g);
436         return (p.first == p.second);
437     }
438 
439     template < typename Graph >
has_no_out_edges(const typename boost::graph_traits<Graph>::vertex_descriptor & v,const Graph & g)440     bool has_no_out_edges(
441         const typename boost::graph_traits< Graph >::vertex_descriptor& v,
442         const Graph& g)
443     {
444         typedef typename boost::graph_traits< Graph >::out_edge_iterator ei;
445         std::pair< ei, ei > p = out_edges(v, g);
446         return (p.first == p.second);
447     }
448 
449 } // namespace graph
450 
451 #include <boost/graph/iteration_macros.hpp>
452 
453 template < class PropertyIn, class PropertyOut, class Graph >
copy_vertex_property(PropertyIn p_in,PropertyOut p_out,Graph & g)454 void copy_vertex_property(PropertyIn p_in, PropertyOut p_out, Graph& g)
455 {
456     BGL_FORALL_VERTICES_T(u, g, Graph)
457     put(p_out, u, get(p_in, g));
458 }
459 
460 template < class PropertyIn, class PropertyOut, class Graph >
copy_edge_property(PropertyIn p_in,PropertyOut p_out,Graph & g)461 void copy_edge_property(PropertyIn p_in, PropertyOut p_out, Graph& g)
462 {
463     BGL_FORALL_EDGES_T(e, g, Graph)
464     put(p_out, e, get(p_in, g));
465 }
466 
467 // Return true if property_map1 and property_map2 differ
468 // for any of the vertices in graph.
469 template < typename PropertyMapFirst, typename PropertyMapSecond,
470     typename Graph >
are_property_maps_different(const PropertyMapFirst property_map1,const PropertyMapSecond property_map2,const Graph & graph)471 bool are_property_maps_different(const PropertyMapFirst property_map1,
472     const PropertyMapSecond property_map2, const Graph& graph)
473 {
474 
475     BGL_FORALL_VERTICES_T(vertex, graph, Graph)
476     {
477         if (get(property_map1, vertex) != get(property_map2, vertex))
478         {
479 
480             return (true);
481         }
482     }
483 
484     return (false);
485 }
486 
487 } /* namespace boost */
488 
489 #endif /* BOOST_GRAPH_UTILITY_HPP*/
490