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//=======================================================================
// Copyright 2001 Jeremy G. Siek, Andrew Lumsdaine, Lie-Quan Lee,
//
// This file is part of the Boost Graph Library
//
// You should have received a copy of the License Agreement for the
// Boost Graph Library along with the software; see the file LICENSE.
// If not, contact Office of Research, Indiana University,
// Bloomington, IN 47405.
//
// Permission to modify the code and to distribute the code is
// granted, provided the text of this NOTICE is retained, a notice if
// the code was modified is included with the above COPYRIGHT NOTICE
// and with the COPYRIGHT NOTICE in the LICENSE file, and that the
// LICENSE file is distributed with the modified code.
//
// LICENSOR MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED.
// By way of example, but not limitation, Licensor MAKES NO
// REPRESENTATIONS OR WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY
// PARTICULAR PURPOSE OR THAT THE USE OF THE LICENSED SOFTWARE COMPONENTS
// OR DOCUMENTATION WILL NOT INFRINGE ANY PATENTS, COPYRIGHTS, TRADEMARKS
// OR OTHER RIGHTS.
//=======================================================================
#include <iostream>
#include <boost/graph/edge_list.hpp>
#include <boost/graph/bellman_ford_shortest_paths.hpp>
int
main()
{
using namespace boost;
// ID numbers for the routers (vertices).
enum
{ A, B, C, D, E, F, G, H, n_vertices };
const int n_edges = 11;
typedef std::pair < int, int >Edge;
// The list of connections between routers stored in an array.
Edge edges[] = {
Edge(A, B), Edge(A, C),
Edge(B, D), Edge(B, E), Edge(C, E), Edge(C, F), Edge(D, H),
Edge(D, E), Edge(E, H), Edge(F, G), Edge(G, H)
};
// Specify the graph type and declare a graph object
typedef edge_list < Edge*, Edge, std::ptrdiff_t, std::random_access_iterator_tag> Graph;
Graph g(edges, edges + n_edges);
// The transmission delay values for each edge.
float delay[] =
{5.0, 1.0, 1.3, 3.0, 10.0, 2.0, 6.3, 0.4, 1.3, 1.2, 0.5};
// Declare some storage for some "external" vertex properties.
char name[] = "ABCDEFGH";
int parent[n_vertices];
for (int i = 0; i < n_vertices; ++i)
parent[i] = i;
float distance[n_vertices];
std::fill(distance, distance + n_vertices, std::numeric_limits < float >::max());
// Specify A as the source vertex
distance[A] = 0;
bool r = bellman_ford_shortest_paths(g, int (n_vertices),
weight_map(make_iterator_property_map
(&delay[0],
get(edge_index, g),
delay[0])).
distance_map(&distance[0]).
predecessor_map(&parent[0]));
if (r)
for (int i = 0; i < n_vertices; ++i)
std::cout << name[i] << ": " << distance[i]
<< " " << name[parent[i]] << std::endl;
else
std::cout << "negative cycle" << std::endl;
return EXIT_SUCCESS;
}
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