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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/config.hpp>
#include <iostream>
#include <vector>
#include <string>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/depth_first_search.hpp>
#include <boost/graph/breadth_first_search.hpp>
#include <boost/property_map.hpp>
#include <boost/graph/graph_utility.hpp> // for boost::make_list
/*
Example of using a visitor with the depth first search
and breadth first search algorithm
Sacramento ---- Reno ---- Salt Lake City
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San Francisco
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San Jose ---- Fresno
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Los Angeles ---- Las Vegas ---- Phoenix
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San Diego
The visitor has three main functions:
discover_vertex(u,g) is invoked when the algorithm first arrives at the
vertex u. This will happen in the depth first or breadth first
order depending on which algorithm you use.
examine_edge(e,g) is invoked when the algorithm first checks an edge to see
whether it has already been there. Whether using BFS or DFS, all
the edges of vertex u are examined immediately after the call to
visit(u).
finish_vertex(u,g) is called when after all the vertices reachable from vertex
u have already been visited.
*/
using namespace std;
using namespace boost;
struct city_arrival : public base_visitor<city_arrival>
{
city_arrival(string* n) : names(n) { }
typedef on_discover_vertex event_filter;
template <class Vertex, class Graph>
inline void operator()(Vertex u, Graph&) {
cout << endl << "arriving at " << names[u] << endl
<< " neighboring cities are: ";
}
string* names;
};
struct neighbor_cities : public base_visitor<neighbor_cities>
{
neighbor_cities(string* n) : names(n) { }
typedef on_examine_edge event_filter;
template <class Edge, class Graph>
inline void operator()(Edge e, Graph& g) {
cout << names[ target(e, g) ] << ", ";
}
string* names;
};
struct finish_city : public base_visitor<finish_city>
{
finish_city(string* n) : names(n) { }
typedef on_finish_vertex event_filter;
template <class Vertex, class Graph>
inline void operator()(Vertex u, Graph&) {
cout << endl << "finished with " << names[u] << endl;
}
string* names;
};
int main(int, char*[])
{
enum { SanJose, SanFran, LA, SanDiego, Fresno, LasVegas, Reno,
Sacramento, SaltLake, Phoenix, N };
string names[] = { "San Jose", "San Francisco", "Los Angeles", "San Diego",
"Fresno", "Las Vegas", "Reno", "Sacramento",
"Salt Lake City", "Phoenix" };
typedef std::pair<int,int> E;
E edge_array[] = { E(Sacramento, Reno), E(Sacramento, SanFran),
E(Reno, SaltLake),
E(SanFran, SanJose),
E(SanJose, Fresno), E(SanJose, LA),
E(LA, LasVegas), E(LA, SanDiego),
E(LasVegas, Phoenix) };
/* Create the graph type we want. */
typedef adjacency_list<vecS, vecS, undirectedS> Graph;
#if defined(BOOST_MSVC) && BOOST_MSVC <= 1300
// VC++ has trouble with the edge iterator constructor
Graph G(N);
for (std::size_t j = 0; j < sizeof(edge_array)/sizeof(E); ++j)
add_edge(edge_array[j].first, edge_array[j].second, G);
#else
Graph G(edge_array, edge_array + sizeof(edge_array)/sizeof(E), N);
#endif
cout << "*** Depth First ***" << endl;
depth_first_search
(G,
visitor(make_dfs_visitor(boost::make_list(city_arrival(names),
neighbor_cities(names),
finish_city(names)))));
cout << endl;
/* Get the source vertex */
boost::graph_traits<Graph>::vertex_descriptor
s = vertex(SanJose,G);
cout << "*** Breadth First ***" << endl;
breadth_first_search
(G, s, visitor(make_bfs_visitor(boost::make_list(city_arrival(names),
neighbor_cities(names),
finish_city(names)))));
return 0;
}
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