21.boost Ford最短路径算法(效率低)

到某个节点最近距离                  最短路径当前节点的父节点

完整代码

 #include <iostream>
 #include <string>
 #include <utility>
 #include <vector>
 #include <deque>
 #include <boost/graph/adjacency_list.hpp>
 //A*寻路算法
 #include <boost\graph\astar_search.hpp>
 //dijsktra
 #include <boost\graph\dijkstra_shortest_paths.hpp>
 //bellman-Ford算法
 #include <boost\graph\bellman_ford_shortest_paths.hpp>
 using namespace std;
 using namespace boost;

 void main()
 {
     //定义节点和边的相关对象和属性
     enum { u, v, x, y, z, N };
     char name[] = { 'u', 'v', 'x', 'y', 'z' };
     typedef std::pair < int, int >E;
     E edge_array[] = { E(u, y), E(u, x), E(u, v), E(v, u),
         E(x, y), E(x, v), E(y, v), E(y, z), E(z, u), E(z, x) };
     int weights[] = { -, , , -, , -, , , ,  };
     int num_arcs = sizeof(edge_array) / sizeof(E);

     //定义所用的图种类和相关类型
     typedef adjacency_list < vecS, vecS, directedS,
         no_property, property < edge_weight_t, int > > Graph;
     //生成图对象
     Graph g(edge_array, edge_array + num_arcs, weights, N);
     graph_traits < Graph >::edge_iterator ei, ei_end;

     //distance用于放置依近到远的路径距离
     std::vector<int> distance(N, (std::numeric_limits < short >::max)());
     //parent用于放置最短路径生成树的各个顶点的父节点
     std::vector<std::size_t> parent(N);
     for (int i = ; i < N; ++i)
         parent[i] = i;

     //将源点z对应距离设为0
     distance[z] = ;
     //应用Bellman-Ford算法
     bool r = bellman_ford_shortest_paths
     (g, int(N), weight_map(get(edge_weight, g)).distance_map(&distance[]).
         predecessor_map(&parent[]));

     if (r)
     {
         std::cout << "源点z到各点的最短路径\n";
         std::cout << "目的点\t" << "最短路径\t" << "最短路径树的父节点:\n";
         for (int i = ; i < N; ++i)
             std::cout << name[i] << ": \t" << distance[i]
             << "\t\t" << name[parent[i]] << std::endl;
     }
     else
         std::cout << "negative cycle" << std::endl;

     system("pause");
 }