Ugly, not-to-be-pushed sucking in of all of Boost to get windows to work.
[dyninst.git] / external / boost / graph / kruskal_min_spanning_tree.hpp
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_MST_KRUSKAL_HPP
12 #define BOOST_GRAPH_MST_KRUSKAL_HPP
13
14 /*
15  *Minimum Spanning Tree 
16  *         Kruskal Algorithm
17  *
18  *Requirement:
19  *      undirected graph
20  */
21
22 #include <vector>
23 #include <queue>
24 #include <functional>
25
26 #include <boost/property_map.hpp>
27 #include <boost/graph/graph_concepts.hpp>
28 #include <boost/graph/named_function_params.hpp>
29 #include <boost/pending/disjoint_sets.hpp>
30 #include <boost/pending/indirect_cmp.hpp>
31
32
33 namespace boost {
34
35   // Kruskal's algorithm for Minimum Spanning Tree
36   //
37   // This is a greedy algorithm to calculate the Minimum Spanning Tree
38   // for an undirected graph with weighted edges. The output will be a
39   // set of edges.
40   //
41
42   namespace detail {
43
44     template <class Graph, class OutputIterator, 
45               class Rank, class Parent, class Weight>
46     void
47     kruskal_mst_impl(const Graph& G, 
48                      OutputIterator spanning_tree_edges, 
49                      Rank rank, Parent parent, Weight weight)
50     {
51       typedef typename graph_traits<Graph>::vertex_descriptor Vertex;
52       typedef typename graph_traits<Graph>::edge_descriptor Edge;
53       function_requires<VertexListGraphConcept<Graph> >();
54       function_requires<EdgeListGraphConcept<Graph> >();
55       function_requires<OutputIteratorConcept<OutputIterator, Edge> >();
56       function_requires<ReadWritePropertyMapConcept<Rank, Vertex> >();
57       function_requires<ReadWritePropertyMapConcept<Parent, Vertex> >();
58       function_requires<ReadablePropertyMapConcept<Weight, Edge> >();
59       typedef typename property_traits<Weight>::value_type W_value;
60       typedef typename property_traits<Rank>::value_type R_value;
61       typedef typename property_traits<Parent>::value_type P_value;
62       function_requires<ComparableConcept<W_value> >();
63       function_requires<ConvertibleConcept<P_value, Vertex> >();
64       function_requires<IntegerConcept<R_value> >();
65
66       disjoint_sets<Rank, Parent>  dset(rank, parent);
67
68       typename graph_traits<Graph>::vertex_iterator ui, uiend;
69       for (boost::tie(ui, uiend) = vertices(G); ui != uiend; ++ui)
70         dset.make_set(*ui);
71
72       typedef indirect_cmp<Weight, std::greater<W_value> > weight_greater;
73       weight_greater wl(weight);
74       std::priority_queue<Edge, std::vector<Edge>, weight_greater> Q(wl);
75       /*push all edge into Q*/
76       typename graph_traits<Graph>::edge_iterator ei, eiend;
77       for (boost::tie(ei, eiend) = edges(G); ei != eiend; ++ei) 
78         Q.push(*ei);
79
80       while (! Q.empty()) {
81         Edge e = Q.top();
82         Q.pop();
83         Vertex u = dset.find_set(source(e, G));
84         Vertex v = dset.find_set(target(e, G));
85         if ( u != v ) {
86           *spanning_tree_edges++ = e;
87           dset.link(u, v);
88         }
89       }
90     }
91
92   } // namespace detail 
93
94   // Named Parameters Variants
95
96   template <class Graph, class OutputIterator>
97   inline void 
98   kruskal_minimum_spanning_tree(const Graph& g,
99                                 OutputIterator spanning_tree_edges)
100   {
101     typedef typename graph_traits<Graph>::vertices_size_type size_type;
102     typedef typename graph_traits<Graph>::vertex_descriptor vertex_t;
103     typedef typename property_map<Graph, vertex_index_t>::type index_map_t;
104     typename graph_traits<Graph>::vertices_size_type
105       n = num_vertices(g);
106     std::vector<size_type> rank_map(n);
107     std::vector<vertex_t> pred_map(n);
108
109     detail::kruskal_mst_impl
110       (g, spanning_tree_edges, 
111        make_iterator_property_map(rank_map.begin(), get(vertex_index, g), rank_map[0]),
112        make_iterator_property_map(pred_map.begin(), get(vertex_index, g), pred_map[0]),
113        get(edge_weight, g));
114   }
115
116   template <class Graph, class OutputIterator, class P, class T, class R>
117   inline void
118   kruskal_minimum_spanning_tree(const Graph& g,
119                                 OutputIterator spanning_tree_edges, 
120                                 const bgl_named_params<P, T, R>& params)
121   {
122     typedef typename graph_traits<Graph>::vertices_size_type size_type;
123     typedef typename graph_traits<Graph>::vertex_descriptor vertex_t;
124     typename graph_traits<Graph>::vertices_size_type n;
125     n = is_default_param(get_param(params, vertex_rank))
126                                    ? num_vertices(g) : 1;
127     std::vector<size_type> rank_map(n);
128     n = is_default_param(get_param(params, vertex_predecessor))
129                                    ? num_vertices(g) : 1;
130     std::vector<vertex_t> pred_map(n);
131     
132     detail::kruskal_mst_impl
133       (g, spanning_tree_edges, 
134        choose_param
135        (get_param(params, vertex_rank), 
136         make_iterator_property_map
137         (rank_map.begin(), 
138          choose_pmap(get_param(params, vertex_index), g, vertex_index), rank_map[0])),
139        choose_param
140        (get_param(params, vertex_predecessor), 
141         make_iterator_property_map
142         (pred_map.begin(), 
143          choose_const_pmap(get_param(params, vertex_index), g, vertex_index), 
144          pred_map[0])),
145        choose_const_pmap(get_param(params, edge_weight), g, edge_weight));
146   }
147     
148 } // namespace boost
149
150
151 #endif // BOOST_GRAPH_MST_KRUSKAL_HPP
152