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//=======================================================================
// Copyright 2001 University of Notre Dame.
// Author: Andrew Janiszewski, 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/test/minimal.hpp>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/random.hpp>
#include <boost/graph/graph_utility.hpp>
#include <boost/graph/graph_archetypes.hpp>
#include <boost/graph/breadth_first_search.hpp>
#include <boost/random/mersenne_twister.hpp>
#ifdef BOOST_NO_ARGUMENT_DEPENDENT_LOOKUP
using namespace boost;
#endif
template <typename DistanceMap, typename ParentMap,
typename Graph, typename ColorMap>
class bfs_testing_visitor
{
typedef typename boost::graph_traits<Graph>::vertex_descriptor Vertex;
typedef typename boost::graph_traits<Graph>::edge_descriptor Edge;
typedef typename boost::color_traits<
typename boost::property_traits<ColorMap>::value_type
> Color;
public:
bfs_testing_visitor(Vertex s, DistanceMap d, ParentMap p, ColorMap c)
: current_distance(0), distance(d), parent(p), color(c), src(s) { }
void initialize_vertex(const Vertex& u, const Graph& ) const {
BOOST_CHECK(get(color, u) == Color::white());
}
void examine_vertex(const Vertex& u, const Graph& ) const {
current_vertex = u;
// Ensure that the distances monotonically increase.
BOOST_CHECK( distance[u] == current_distance
|| distance[u] == current_distance + 1 );
if (distance[u] == current_distance + 1) // new level
++current_distance;
}
void discover_vertex(const Vertex& u, const Graph& ) const {
BOOST_CHECK( get(color, u) == Color::gray() );
if (u == src) {
current_vertex = src;
} else {
BOOST_CHECK( parent[u] == current_vertex );
BOOST_CHECK( distance[u] == current_distance + 1 );
BOOST_CHECK( distance[u] == distance[parent[u]] + 1 );
}
}
void examine_edge(const Edge& e, const Graph& g) const {
BOOST_CHECK( source(e, g) == current_vertex );
}
void tree_edge(const Edge& e, const Graph& g) const {
BOOST_CHECK( get(color, target(e, g)) == Color::white() );
Vertex u = source(e, g), v = target(e, g);
BOOST_CHECK( distance[u] == current_distance );
parent[v] = u;
distance[v] = distance[u] + 1;
}
void non_tree_edge(const Edge& e, const Graph& g) const {
BOOST_CHECK( color[target(e, g)] != Color::white() );
if (boost::is_directed(g))
// cross or back edge
BOOST_CHECK(distance[target(e, g)] <= distance[source(e, g)] + 1);
else {
// cross edge (or going backwards on a tree edge)
BOOST_CHECK(distance[target(e, g)] == distance[source(e, g)]
|| distance[target(e, g)] == distance[source(e, g)] + 1
|| distance[target(e, g)] == distance[source(e, g)] - 1
);
}
}
void gray_target(const Edge& e, const Graph& g) const {
BOOST_CHECK( color[target(e, g)] == Color::gray() );
}
void black_target(const Edge& e, const Graph& g) const {
BOOST_CHECK( color[target(e, g)] == Color::black() );
// All vertices adjacent to a black vertex must already be discovered
typename boost::graph_traits<Graph>::adjacency_iterator ai, ai_end;
for (boost::tie(ai, ai_end) = adjacent_vertices(target(e, g), g);
ai != ai_end; ++ai)
BOOST_CHECK( color[*ai] != Color::white() );
}
void finish_vertex(const Vertex& u, const Graph& ) const {
BOOST_CHECK( color[u] == Color::black() );
}
private:
mutable Vertex current_vertex;
mutable typename boost::property_traits<DistanceMap>::value_type
current_distance;
DistanceMap distance;
ParentMap parent;
ColorMap color;
Vertex src;
};
template <class Graph>
struct bfs_test
{
typedef boost::graph_traits<Graph> Traits;
typedef typename Traits::vertices_size_type
vertices_size_type;
static void go(vertices_size_type max_V) {
typedef typename Traits::vertex_descriptor vertex_descriptor;
typedef boost::color_traits<boost::default_color_type> Color;
vertices_size_type i;
typename Traits::edges_size_type j;
typename Traits::vertex_iterator ui, ui_end;
boost::mt19937 gen;
for (i = 0; i < max_V; ++i)
for (j = 0; j < i*i; ++j) {
Graph g;
boost::generate_random_graph(g, i, j, gen);
// declare the "start" variable
vertex_descriptor start = boost::random_vertex(g, gen);
// vertex properties
std::vector<int> distance(i, (std::numeric_limits<int>::max)());
distance[start] = 0;
std::vector<vertex_descriptor> parent(i);
for (boost::tie(ui, ui_end) = vertices(g); ui != ui_end; ++ui)
parent[*ui] = *ui;
std::vector<boost::default_color_type> color(i);
// Get vertex index map
typedef typename boost::property_map<Graph, boost::vertex_index_t>::const_type idx_type;
idx_type idx = get(boost::vertex_index, g);
// Make property maps from vectors
typedef
boost::iterator_property_map<std::vector<int>::iterator, idx_type>
distance_pm_type;
distance_pm_type distance_pm(distance.begin(), idx);
typedef
boost::iterator_property_map<typename std::vector<vertex_descriptor>::iterator, idx_type>
parent_pm_type;
parent_pm_type parent_pm(parent.begin(), idx);
typedef
boost::iterator_property_map<std::vector<boost::default_color_type>::iterator, idx_type>
color_pm_type;
color_pm_type color_pm(color.begin(), idx);
// Create the testing visitor.
bfs_testing_visitor<distance_pm_type, parent_pm_type, Graph,
color_pm_type>
vis(start, distance_pm, parent_pm, color_pm);
boost::breadth_first_search(g, start,
visitor(vis).
color_map(color_pm));
// All white vertices should be unreachable from the source.
for (boost::tie(ui, ui_end) = vertices(g); ui != ui_end; ++ui)
if (color[*ui] == Color::white()) {
std::vector<boost::default_color_type> color2(i, Color::white());
BOOST_CHECK(!boost::is_reachable(start, *ui, g, color_pm_type(color2.begin(), idx)));
}
// The shortest path to a child should be one longer than
// shortest path to the parent.
for (boost::tie(ui, ui_end) = vertices(g); ui != ui_end; ++ui)
if (parent[*ui] != *ui) // *ui not the root of the bfs tree
BOOST_CHECK(distance[*ui] == distance[parent[*ui]] + 1);
}
}
};
int test_main(int argc, char* argv[])
{
using namespace boost;
int max_V = 7;
if (argc > 1)
max_V = atoi(argv[1]);
bfs_test< adjacency_list<vecS, vecS, directedS> >::go(max_V);
bfs_test< adjacency_list<vecS, vecS, undirectedS> >::go(max_V);
return 0;
}
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