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fixed to do topological order (not reverse topo)

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[SVN r10197]
This commit is contained in:
Jeremy Siek
2001-05-23 16:39:49 +00:00
parent 27960ba125
commit db5a2b138d
1 changed files with 41 additions and 52 deletions
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93
include/boost/graph/dag_shortest_paths.hpp
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@@ -1,10 +1,8 @@
#ifndef BOOST_GRAPH_DAG_SHORTEST_PATHS_HPP
#define BOOST_GRAPH_DAG_SHORTEST_PATHS_HPP
#include <boost/graph/relax.hpp>
#include <boost/graph/depth_first_search.hpp>
// UNDER CONSTRUCTION
#include <boost/graph/topological_sort.hpp>
#include <boost/graph/dijkstra_shortest_paths.hpp>
// single-source shortest paths for a Directed Acyclic Graph (DAG)
@@ -12,42 +10,10 @@ namespace boost {
namespace detail {
template <class DijkstraVisitor,
class WeightMap, class DistanceMap,
class BinaryFunction, class BinaryPredicate>
struct dag_sp_visitor : public dfs_visitor<>
{
dag_sp_visitor(DijkstraVisitor vis, WeightMap w, DistanceMap d,
BinaryFunction cmb, BinaryPredicate cmp)
: m_vis(vis), m_weight(w), m_distance(d),
m_combine(cmb), m_compare(cmp) { }
template <class Vertex, class Graph>
void finish_vertex(const Vertex& u, const Graph& g)
{
m_vis.examine_vertex(u, g);
typename graph_traits<Graph>::out_edge_iterator e, e_end;
for (tie(e, e_end) = out_edges(u, g); e != e_end; ++e) {
m_vis.discover_vertex(target(*e, g), g);
bool decreased = relax(*e, g, m_weight, m_distance,
m_combine, m_compare);
if (decreased)
m_vis.edge_relaxed(*e, g);
else
m_vis.edge_not_relaxed(*e, g);
}
m_vis.finish_vertex(u, g);
}
WeightMap m_weight;
DistanceMap m_distance;
BinaryFunction m_combine;
BinaryPredicate m_compare;
};
// Initalize distances and call depth first search
template <class VertexListGraph, class DijkstraVisitor,
class DistanceMap, class WeightMap, class ColorMap,
class PredecessorMap,
class Compare, class Combine,
class DistInf, class DistZero>
inline void
@@ -55,30 +21,48 @@ namespace boost {
(const VertexListGraph& g,
typename graph_traits<VertexListGraph>::vertex_descriptor s,
DistanceMap distance, WeightMap weight, ColorMap color,
PredecessorMap pred,
DijkstraVisitor vis, Compare compare, Combine combine,
DistInf init, DistZero zero)
DistInf inf_gen, DistZero zero)
{
typedef typename graph_traits<VertexListGraph>::vertex_descriptor Vertex;
std::vector<Vertex> rev_topo_order;
rev_topo_order.reserve(num_vertices(g));
topological_sort(g, std::back_inserter(rev_topo_order));
typename graph_traits<VertexListGraph>::vertex_iterator ui, ui_end;
for (tie(ui, ui_end) = vertices(g); ui != ui_end; ++ui) {
put(distance, *ui, init());
put(distance, *ui, inf_gen());
put(pred, *ui, *ui);
vis.initialize_vertex(*ui, g);
}
put(distance, s, zero());
vis.discover_vertex(s, g);
dag_sp_visitor<DijkstraVisitor, WeightMap, DistanceMap,
Combine, Compare> v(vis, weight, distance, combine, compare);
depth_first_visit(g, s, v, color);
std::vector<Vertex>::reverse_iterator i;
for (i = rev_topo_order.rbegin(); i != rev_topo_order.rend(); ++i) {
Vertex u = *i;
vis.examine_vertex(u, g);
typename graph_traits<VertexListGraph>::out_edge_iterator e, e_end;
for (tie(e, e_end) = out_edges(u, g); e != e_end; ++e) {
vis.discover_vertex(target(*e, g), g);
bool decreased = relax(*e, g, weight, pred, distance,
combine, compare);
if (decreased)
vis.edge_relaxed(*e, g);
else
vis.edge_not_relaxed(*e, g);
}
vis.finish_vertex(u, g);
}
}
// Defaults are the same as Dijkstra's algorithm
// Handle Distance Compare, Combine, Inf and Zero defaults
template <class VertexListGraph, class DijkstraVisitor,
class DistanceMap, class WeightMap, class ColorMap,
class Params>
class DistanceMap, class WeightMap, class ColorMap,
class IndexMap, class Params>
inline void
dag_sp_dispatch2
(const VertexListGraph& g,
@@ -87,8 +71,11 @@ namespace boost {
DijkstraVisitor vis, const Params& params)
{
typedef typename property_traits<DistanceMap>::value_type D;
dummy_property_map p_map;
detail::dag_sp_dispatch3
(g, s, distance, weight, color, vis,
(g, s, distance, weight, color,
choose_param(get_param(params, vertex_predecessor), p_map),
vis,
choose_param(get_param(params, distance_compare_t()), std::less<D>()),
choose_param(get_param(params, distance_combine_t()), std::plus<D>()),
choose_param(get_param(params, distance_inf_t()),
@@ -114,15 +101,17 @@ namespace boost {
std::vector<T> distance_map(n);
n = is_default_param(color) ? num_vertices(g) : 1;
std::vector<default_color_type> color_map(n);
dag_sp_dispatch2
(g, s,
choose_param(distance,
make_iterator_property_map(distance_map.begin(), id,
distance_map[0])),
distance_map[0])),
weight,
choose_param(color,
make_iterator_property_map(color_map.begin(), id, color_map[0])),
vis, params);
make_iterator_property_map(color_map.begin(), id,
color_map[0])),
id, vis, params);
}
} // namespace detail
@@ -139,9 +128,9 @@ namespace boost {
detail::dag_sp_dispatch1
(g, s,
get_param(params, vertex_distance),
choose_pmap(get_param(params, edge_weight), g, edge_weight),
choose_const_pmap(get_param(params, edge_weight), g, edge_weight),
get_param(params, vertex_color),
choose_pmap(get_param(params, vertex_index), g, vertex_index),
choose_const_pmap(get_param(params, vertex_index), g, vertex_index),
choose_param(get_param(params, graph_visitor),
make_dijkstra_visitor(null_vis)),
params);