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//=======================================================================
// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
//=======================================================================
#include <boost/config.hpp>
#include <algorithm>
#include <vector>
#include <utility>
#include <iostream>
#include <boost/graph/visitors.hpp>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/graph_utility.hpp>
#include <boost/graph/neighbor_bfs.hpp>
#include <boost/property_map.hpp>
/*
Sample Output:
0 --> 2
1 --> 1 3 4
2 --> 1 3 4
3 --> 1 4
4 --> 0 1
distances: 0 2 1 2 1
parent[0] = 0
parent[1] = 2
parent[2] = 0
parent[3] = 2
parent[4] = 0
*/
using namespace boost;
template <class ParentDecorator>
struct print_parent {
print_parent(const ParentDecorator& p_) : p(p_) { }
template <class Vertex>
void operator()(const Vertex& v) const {
std::cout << "parent[" << v << "] = " << p[v] << std::endl;
}
ParentDecorator p;
};
template <class DistanceMap, class PredecessorMap, class ColorMap>
class distance_and_pred_visitor : public neighbor_bfs_visitor<>
{
typedef typename property_traits<ColorMap>::value_type ColorValue;
typedef color_traits<ColorValue> Color;
public:
distance_and_pred_visitor(DistanceMap d, PredecessorMap p, ColorMap c)
: m_distance(d), m_predecessor(p), m_color(c) { }
template <class Edge, class Graph>
void tree_out_edge(Edge e, const Graph& g) const
{
typename graph_traits<Graph>::vertex_descriptor
u = source(e, g), v = target(e, g);
put(m_distance, v, get(m_distance, u) + 1);
put(m_predecessor, v, u);
}
template <class Edge, class Graph>
void tree_in_edge(Edge e, const Graph& g) const
{
typename graph_traits<Graph>::vertex_descriptor
u = source(e, g), v = target(e, g);
put(m_distance, u, get(m_distance, v) + 1);
put(m_predecessor, u, v);
}
DistanceMap m_distance;
PredecessorMap m_predecessor;
ColorMap m_color;
};
int main(int , char* [])
{
typedef adjacency_list<
mapS, vecS, bidirectionalS,
property<vertex_color_t, default_color_type>
> Graph;
typedef property_map<Graph, vertex_color_t>::type
ColorMap;
Graph G(5);
add_edge(0, 2, G);
add_edge(1, 1, G);
add_edge(1, 3, G);
add_edge(1, 4, G);
add_edge(2, 1, G);
add_edge(2, 3, G);
add_edge(2, 4, G);
add_edge(3, 1, G);
add_edge(3, 4, G);
add_edge(4, 0, G);
add_edge(4, 1, G);
typedef Graph::vertex_descriptor Vertex;
// Array to store predecessor (parent) of each vertex. This will be
// used as a Decorator (actually, its iterator will be).
std::vector<Vertex> p(num_vertices(G));
// VC++ version of std::vector has no ::pointer, so
// I use ::value_type* instead.
typedef std::vector<Vertex>::value_type* Piter;
// Array to store distances from the source to each vertex . We use
// a built-in array here just for variety. This will also be used as
// a Decorator.
typedef graph_traits<Graph>::vertices_size_type size_type;
size_type d[5];
std::fill_n(d, 5, 0);
// The source vertex
Vertex s = *(vertices(G).first);
p[s] = s;
distance_and_pred_visitor<size_type*, Vertex*, ColorMap>
vis(d, &p[0], get(vertex_color, G));
neighbor_breadth_first_search
(G, s, visitor(vis).
color_map(get(vertex_color, G)));
print_graph(G);
if (num_vertices(G) < 11) {
std::cout << "distances: ";
#ifdef BOOST_OLD_STREAM_ITERATORS
std::copy(d, d + 5, std::ostream_iterator<int, char>(std::cout, " "));
#else
std::copy(d, d + 5, std::ostream_iterator<int>(std::cout, " "));
#endif
std::cout << std::endl;
std::for_each(vertices(G).first, vertices(G).second,
print_parent<Piter>(&p[0]));
}
return 0;
}
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