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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/graph/dag_shortest_paths.hpp>
#include <boost/graph/adjacency_list.hpp>
#include <iostream>
// Example from Introduction to Algorithms by Cormen, et all p.537.
// Sample output:
// r: inifinity
// s: 0
// t: 2
// u: 6
// v: 5
// x: 3
int main()
{
using namespace boost;
typedef adjacency_list< vecS, vecS, directedS,
property< vertex_distance_t, int >, property< edge_weight_t, int > >
graph_t;
graph_t g(6);
enum verts
{
r,
s,
t,
u,
v,
x
};
char name[] = "rstuvx";
add_edge(r, s, 5, g);
add_edge(r, t, 3, g);
add_edge(s, t, 2, g);
add_edge(s, u, 6, g);
add_edge(t, u, 7, g);
add_edge(t, v, 4, g);
add_edge(t, x, 2, g);
add_edge(u, v, -1, g);
add_edge(u, x, 1, g);
add_edge(v, x, -2, g);
property_map< graph_t, vertex_distance_t >::type d_map
= get(vertex_distance, g);
#if defined(BOOST_MSVC) && BOOST_MSVC <= 1300
// VC++ has trouble with the named-parameter mechanism, so
// we make a direct call to the underlying implementation function.
std::vector< default_color_type > color(num_vertices(g));
std::vector< std::size_t > pred(num_vertices(g));
default_dijkstra_visitor vis;
std::less< int > compare;
closed_plus< int > combine;
property_map< graph_t, edge_weight_t >::type w_map = get(edge_weight, g);
dag_shortest_paths(g, s, d_map, w_map, &color[0], &pred[0], vis, compare,
combine, (std::numeric_limits< int >::max)(), 0);
#else
dag_shortest_paths(g, s, distance_map(d_map));
#endif
graph_traits< graph_t >::vertex_iterator vi, vi_end;
for (boost::tie(vi, vi_end) = vertices(g); vi != vi_end; ++vi)
if (d_map[*vi] == (std::numeric_limits< int >::max)())
std::cout << name[*vi] << ": inifinity\n";
else
std::cout << name[*vi] << ": " << d_map[*vi] << '\n';
return 0;
}
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