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// (C) Copyright Jeremy Siek 2004
// 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)
// From Louis Lavery <Louis@devilsChimney.co.uk>
/*Expected Output:-
A: 0 A
B: 11 A
Actual Output:-
A: 0 A
B: 2147483647 B
*/
#include <iostream>
#include <iomanip>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/bellman_ford_shortest_paths.hpp>
#include <boost/cstdlib.hpp>
#include <boost/test/minimal.hpp>
int test_main(int, char*[])
{
using namespace boost;
enum { A, B, Z };
char const name[] = "ABZ";
int const numVertex = static_cast<int>(Z) + 1;
typedef std::pair<int,int> Edge;
Edge edge_array[] = {Edge(B,A)};
int const numEdges = sizeof(edge_array) / sizeof(Edge);
int const weight[numEdges] = {11};
typedef adjacency_list<vecS,vecS,undirectedS,
no_property,property<edge_weight_t,int> > Graph;
Graph g(edge_array, edge_array + numEdges, numVertex);
Graph::edge_iterator ei, ei_end;
property_map<Graph,edge_weight_t>::type
weight_pmap = get(edge_weight, g);
int i = 0;
for(boost::tie(ei, ei_end) = edges(g); ei != ei_end; ++ei, ++i)
weight_pmap[*ei] = weight[i];
std::vector<int> parent(numVertex);
for(i = 0; i < numVertex; ++i)
parent[i] = i;
int inf = (std::numeric_limits<int>::max)();
std::vector<int> distance(numVertex, inf);
distance[A] = 0; // Set source distance to zero
bool const r = bellman_ford_shortest_paths
(g, int (numVertex),
weight_pmap,
boost::make_iterator_property_map(parent.begin(), get(boost::vertex_index, g)),
boost::make_iterator_property_map(distance.begin(), get(boost::vertex_index, g)),
closed_plus<int>(),
std::less<int>(),
default_bellman_visitor());
if (r) {
for(int i = 0; i < numVertex; ++i) {
std::cout << name[i] << ": ";
if (distance[i] == inf)
std::cout << std::setw(3) << "inf";
else
std::cout << std::setw(3) << distance[i];
std::cout << " " << name[parent[i]] << std::endl;
}
} else {
std::cout << "negative cycle" << std::endl;
}
#if !(defined(__INTEL_COMPILER) && __INTEL_COMPILER <= 700) && !(defined(BOOST_MSVC) && BOOST_MSVC <= 1300)
graph_traits<Graph>::vertex_descriptor s = vertex(A, g);
std::vector<int> parent2(numVertex);
std::vector<int> distance2(numVertex, 17);
bool const r2 = bellman_ford_shortest_paths
(g,
weight_map(weight_pmap).
distance_map(boost::make_iterator_property_map(distance2.begin(), get(boost::vertex_index, g))).
predecessor_map(boost::make_iterator_property_map(parent2.begin(), get(boost::vertex_index, g))).
root_vertex(s));
if (r2) {
for(int i = 0; i < numVertex; ++i) {
std::cout << name[i] << ": ";
if (distance2[i] == inf)
std::cout << std::setw(3) << "inf";
else
std::cout << std::setw(3) << distance2[i];
std::cout << " " << name[parent2[i]] << std::endl;
}
} else {
std::cout << "negative cycle" << std::endl;
}
BOOST_CHECK(r == r2);
if (r && r2) {
BOOST_CHECK(parent == parent2);
BOOST_CHECK(distance == distance2);
}
#endif
return boost::exit_success;
}
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