graph/example/min_max_paths.cpp
Jeremy Siek ebc42db0ac dijkstra change updates
[SVN r10944]
2001-08-28 01:03:34 +00:00

103 lines
3.0 KiB
C++

//=======================================================================
// Copyright 1997-2001 University of Notre Dame.
// Authors: 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, University of Notre Dame, Notre
// Dame, IN 46556.
//
// Permission to modify the code and to distribute modified code is
// granted, provided the text of this NOTICE is retained, a notice that
// 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 <boost/config.hpp>
#include <iostream>
#include <boost/graph/graph_traits.hpp>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/dijkstra_shortest_paths.hpp>
#include <boost/graph/visitors.hpp>
#include <boost/graph/transpose_graph.hpp>
/* Output:
distances from start vertex:
distance(a) = 0
distance(b) = 3
distance(c) = 1
distance(d) = 3
distance(e) = 3
min-max paths tree
a --> c
b -->
c --> d
d --> e
e --> b
*/
int max_path(int x, int y) {
return std::max(x, y);
}
int
main(int , char* [])
{
using namespace boost;
typedef adjacency_list<listS, vecS, directedS,
no_property, property<edge_weight_t, int> > Graph;
typedef graph_traits<Graph>::vertex_descriptor Vertex;
typedef std::pair<int,int> E;
const char name[] = "abcdef";
const int num_nodes = 6;
E edges[] = { E(0,2), E(1,1), E(1,3), E(1,4), E(2,1), E(2,3),
E(3,4), E(4,0), E(4,1) };
int weights[] = { 1, 2, 1, 2, 7, 3, 1, 1, 1};
const int n_edges = sizeof(edges)/sizeof(E);
Graph G(num_nodes, edges, edges + n_edges, weights);
std::vector<Vertex> p(num_vertices(G));
std::vector<int> d(num_vertices(G));
Vertex s = *(vertices(G).first);
dijkstra_shortest_paths
(G, s, distance_map(&d[0]).
predecessor_map(&p[0]).
distance_extend(max_path));
std::cout << "distances from start vertex:" << std::endl;
graph_traits<Graph>::vertex_iterator vi, vend;
for(tie(vi,vend) = vertices(G); vi != vend; ++vi)
std::cout << "distance(" << name[*vi] << ") = " << d[*vi] << std::endl;
std::cout << std::endl;
std::cout << "min-max paths tree" << std::endl;
adjacency_list<> tree(num_nodes);
for(tie(vi,vend) = vertices(G); vi != vend; ++vi)
if (*vi != p[*vi])
add_edge(p[*vi], *vi, tree);
print_graph(tree, name);
return 0;
}