//整理 by RobinKin from DevonIT.inc
#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
|
San Francisco
|
San Jose ---- Fresno
|
Los Angeles ---- Los Vegas ---- Pheonix
|
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;
//到達結點時 Operator()
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;
};
//顯示鄰接結點時 。調用 Operator()
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;
};
//某結點的所有鄰接結點都已經被訪問過時 調用 Operator()
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, LosVegas, Reno,
Sacramento, SaltLake, Pheonix, N };
string names[] = { "San Jose", "San Francisco", "San Jose",
"San Francisco", "Los Angeles", "San DIEgo",
"Fresno", "Los Vegas", "Reno", "Sacramento",
"Salt Lake City", "Pheonix" };
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, LosVegas), E(LA, SanDIEgo),
E(LosVegas, Pheonix) };
/* Create the graph type we want. */
typedef adjacency_list<vecS, vecS, undirectedS> Graph;
Graph G(edge_array, edge_array + sizeof(edge_array)/sizeof(E), N);
cout << "*** Depth First ***" << endl;
//第 1 2 3 個參數分別是 arrival neighbor finish
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;
}
//輸出：
*** Depth First ***
arriving at San Jose
neighboring citIEs are: San Francisco,
arriving at San Francisco
neighboring citIEs are: Los Vegas,
arriving at Los Vegas
neighboring citIEs are: Fresno,
arriving at Fresno
neighboring citIEs are: Los Vegas, Reno,
arriving at Reno
neighboring citIEs are: Fresno,
finished with Reno
finished with Fresno
San Francisco,
finished with Los Vegas
San Jose,
finished with San Francisco
Los Angeles,
arriving at Los Angeles
neighboring citIEs are: San Jose,
finished with Los Angeles