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// Boost.Graph library isomorphism test
// Copyright (C) 2001 Doug Gregor (gregod@cs.rpi.edu)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
// For more information, see http://www.boost.org
//
// Revision History:
//
// 29 Nov 2001 Jeremy Siek
// Changed to use Boost.Random.
// 29 Nov 2001 Doug Gregor
// Initial checkin.
#define BOOST_INCLUDE_MAIN
#include <boost/test/test_tools.hpp>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/isomorphism.hpp>
#include <boost/property_map.hpp>
#include <boost/random/uniform_real.hpp>
#include <boost/random/mersenne_twister.hpp>
#include <iostream>
#include <fstream>
#include <map>
#include <algorithm>
#include <cstdlib>
#include <ctime>
using namespace boost;
// Verify that the given mapping iso_map from the vertices of g1 to the
// vertices of g2 describes an isomorphism.
// Note: this could be made much faster by specializing based on the graph
// concepts modeled, but since we're verifying an O(n^(lg n)) algorithm,
// O(n^4) won't hurt us.
template<typename Graph1, typename Graph2, typename IsoMap>
inline bool verify_isomorphism(const Graph1& g1, const Graph2& g2,
IsoMap iso_map)
{
if (num_vertices(g1) != num_vertices(g2) || num_edges(g1) != num_edges(g2))
return false;
for (typename graph_traits<Graph1>::edge_iterator e1 = edges(g1).first;
e1 != edges(g1).second; ++e1) {
bool found_edge = false;
for (typename graph_traits<Graph2>::edge_iterator e2 = edges(g2).first;
e2 != edges(g2).second && !found_edge; ++e2) {
if (source(*e2, g2) == get(iso_map, source(*e1, g1)) &&
target(*e2, g2) == get(iso_map, target(*e1, g1))) {
found_edge = true;
}
}
if (!found_edge)
return false;
}
return true;
}
template <typename Generator>
struct random_functor {
random_functor(Generator& g) : g(g) { }
std::size_t operator()(std::size_t n) {
boost::uniform_int<boost::mt19937, std::size_t> x(g, 0, n-1);
return x();
}
Generator& g;
};
template<typename Graph1, typename Graph2>
void randomly_permute_graph(const Graph1& g1, Graph2& g2)
{
// Need a clean graph to start with
assert(num_vertices(g2) == 0);
assert(num_edges(g2) == 0);
typedef typename graph_traits<Graph1>::vertex_descriptor vertex1;
typedef typename graph_traits<Graph2>::vertex_descriptor vertex2;
typedef typename graph_traits<Graph1>::edge_iterator edge_iterator;
boost::mt19937 gen;
random_functor<boost::mt19937> rand_fun(gen);
// Decide new order
std::vector<vertex1> orig_vertices(vertices(g1).first, vertices(g1).second);
std::random_shuffle(orig_vertices.begin(), orig_vertices.end(), rand_fun);
std::map<vertex1, vertex2> vertex_map;
for (std::size_t i = 0; i < num_vertices(g1); ++i) {
vertex_map[orig_vertices[i]] = add_vertex(g2);
}
for (edge_iterator e = edges(g1).first; e != edges(g1).second; ++e) {
add_edge(vertex_map[source(*e, g1)], vertex_map[target(*e, g1)], g2);
}
}
template<typename Graph>
void generate_random_digraph(Graph& g, double edge_probability)
{
typedef typename graph_traits<Graph>::vertex_iterator vertex_iterator;
boost::mt19937 random_gen;
boost::uniform_real<boost::mt19937, double>
random_dist(random_gen, 0.0, 1.0);
for (vertex_iterator u = vertices(g).first; u != vertices(g).second; ++u) {
vertex_iterator v = u;
++v;
for (; v != vertices(g).second; ++v) {
if (random_dist() <= edge_probability)
add_edge(*u, *v, g);
}
}
}
void test_isomorphism(int n, double edge_probability)
{
typedef adjacency_list<vecS, vecS, bidirectionalS> graph1;
typedef adjacency_list<listS, listS, bidirectionalS,
property<vertex_index_t, int> > graph2;
graph1 g1(n);
generate_random_digraph(g1, edge_probability);
graph2 g2;
randomly_permute_graph(g1, g2);
int v_idx = 0;
for (graph2::vertex_iterator v = vertices(g2).first;
v != vertices(g2).second; ++v) {
put(vertex_index_t(), g2, *v, v_idx++);
}
std::map<graph1::vertex_descriptor, graph2::vertex_descriptor> mapping;
bool isomorphism_correct;
clock_t start = clock();
BOOST_TEST(isomorphism_correct = isomorphism
(g1, g2, isomorphism_map(make_assoc_property_map(mapping))));
clock_t end = clock();
std::cout << "Elapsed time (clock cycles): " << (end - start) << std::endl;
bool verify_correct;
BOOST_TEST(verify_correct =
verify_isomorphism(g1, g2, make_assoc_property_map(mapping)));
if (!isomorphism_correct || !verify_correct) {
// Output graph 1
{
std::ofstream out("isomorphism_failure.bg1");
out << num_vertices(g1) << std::endl;
for (graph1::edge_iterator e = edges(g1).first;
e != edges(g1).second; ++e) {
out << get(vertex_index_t(), g1, source(*e, g1)) << ' '
<< get(vertex_index_t(), g1, target(*e, g1)) << std::endl;
}
}
// Output graph 2
{
std::ofstream out("isomorphism_failure.bg2");
out << num_vertices(g2) << std::endl;
for (graph2::edge_iterator e = edges(g2).first;
e != edges(g2).second; ++e) {
out << get(vertex_index_t(), g2, source(*e, g2)) << ' '
<< get(vertex_index_t(), g2, target(*e, g2)) << std::endl;
}
}
}
}
int test_main(int argc, char* argv[])
{
if (argc < 3) {
test_isomorphism(30, 0.45);
return 0;
}
int n = atoi(argv[1]);
double edge_prob = atof(argv[2]);
test_isomorphism(n, edge_prob);
return 0;
}
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