看到一篇文章，编译运行了一下，发现和预想的结果不一致，所以，仔细研究了一下，对其做了调整。
这个例子能让我们领略BGL的强大。
//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).
fiu have already been visited.hen after all the vertices reachable from vertex
*/
using namespace std;
using namespace boost;
//到达结点时 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;
}
string* names;
};
//显示邻接结点时 。调用 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 << " neighboring cities are: ";
cout << names[ target(e, g) ] << ", ";
}
string* names;
};
//某结点的所有邻接结点都已经被访问过时 调用 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", "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. */
//这里用邻接表来表示一个图
typedef adjacency_list<vecS, vecS, undirectedS> Graph;
#if defined(BOOST_MSVC) && BOOST_MSVC <= 1300
//VC++ 不能处理迭代器的构造函数
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
//参数分别为边起始迭代器、中止迭代器、顶点个数
Graph G(edge_array, edge_array + sizeof(edge_array)/sizeof(E), N);
#endif
cout << "*** Depth First ***" << endl;
//第 1 2 3 个参数分别是 arrival neighbor finish
//深度遍历图，当某一事件发生时，执行预定义的操作
depth_first_search
(G,
visitor(make_dfs_visitor(boost::make_list(city_arrival(names),
neighbor_cities(names),
finish_city(names)))));
cout << endl;
//定义源节点
boost::graph_traits<Graph>::vertex_descriptor
s = vertex(SanJose,G);
cout << "*** Breadth First ***" << endl;
//广度遍历图，当某一事件发生时，执行预定义的操作
breadth_first_search
(G, s, visitor(make_bfs_visitor(boost::make_list(city_arrival(names),
neighbor_cities(names),
finish_city(names)))));
return 0;
}