文章目录
- 示例
- 代码
示例
最短路径: A -> C -> D -> F -> E -> G 长度 16
代码
#include <iostream>
#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/dijkstra_shortest_paths.hpp>
#include <boost/graph/graphviz.hpp>
#include <boost/graph/properties.hpp>
#include <boost/property_map/property_map.hpp>
#include <boost/graph/named_function_params.hpp>
#include <vector>
#include <string>
using namespace std;
using namespace boost;
struct Node{
string id_;
};
struct EdgeProperty{
int id_;
int weight_;
EdgeProperty(int id,int weight){
id_=id;
weight_=weight;
}
};
typedef boost::adjacency_list < boost::listS,
boost::vecS,
boost::undirectedS,
Node,
boost::property <boost::edge_weight_t, unsigned long>> graph_t;
typedef boost::graph_traits <graph_t>::vertex_descriptor vertex_descriptor;
typedef boost::graph_traits <graph_t>::edge_descriptor edge_descriptor;
enum {A, B, C, D, E, F,G };
string vtx[]={"A","B","C","D","E","F","G"};
/* 获取路径经过结点的信息 */
void GetPath(int fromId,int toId,vector<vertex_descriptor>& vPredecessor,std::string& strPath){
vector<int> vecPath;
while(fromId!=toId){
vecPath.push_back(toId);
//因为本例子的特殊性和自己很懒,所以可以直接取值
toId = vPredecessor[toId];
}
vecPath.push_back(toId);
vector<int>::reverse_iterator pIter = vecPath.rbegin();
strPath="路径:";
std::string strOperator="->";
string c[20]={};
for(;pIter!=vecPath.rend();pIter++){
// sprintf(c,"%c",vtx[*pIter]);
if(*pIter!=fromId){
strPath+=(strOperator+vtx[*pIter]);
}
else{
strPath+=vtx[*pIter];
}
}
}
int main()
{
/* modify vertex */
graph_t g(7);
for(int i=0;i< boost::num_vertices(g); i++){
g[i].id_=vtx[i];
}
/* modify edge and weight */
typedef std::pair<int, int> Edge;
boost::property_map<graph_t,edge_weight_t>::type weightmap= get(boost::edge_weight_t(), g);
Edge edge_array[] = { Edge(A,B), Edge(A,C), Edge(B,C), Edge(B,D),Edge(B,E),
Edge(C,D),
Edge(D,F),
Edge(E,F),Edge(E,G),
Edge(F,G)};
int weight[]={2,5,4,6,10,2,1,3,5,9};
int num_edges = sizeof(edge_array)/sizeof(edge_array[0]);
for (int i = 0; i < num_edges; ++i){
auto ed=add_edge(edge_array[i].first, edge_array[i].second, g);
boost::put(boost::edge_weight_t(), g, ed.first,weight[i]);
}
/* 路径计算结果定义*/
//存储从起始结点到其他结点的路径上经过的最后一个中间结点序号
vector<vertex_descriptor> vPredecessor(boost::num_vertices(g));
//存储起始结点到其他结点的路径的距离
vector<unsigned long> vDistance(boost::num_vertices(g));
/*路径探索起始点定义*/
vertex_descriptor s = boost::vertex(0, g);
boost::property_map<graph_t, boost::vertex_index_t>::type pmpIndexmap = boost::get(boost::vertex_index, g);
boost::dijkstra_shortest_paths(
g, // IN: 图
s, // IN: 起始点
&vPredecessor[0], // OUT:存储从起始结点到其他结点的路径上经过的最后一个中间结点序号
&vDistance[0], // UTIL/OUT:存储起始结点到其他结点的路径的距离
weightmap, // IN: 权重矩阵
pmpIndexmap, // IN:
std::less<unsigned long>(), // IN: 对比函数
boost::closed_plus<unsigned long>(), // IN: 用来计算路径距离的混合函数
std::numeric_limits<unsigned long>::max(), // IN: 距离最大值
0,
boost::default_dijkstra_visitor()); // OUT:指定每个点所运行的动作
std::string strPath;
GetPath(0,6,vPredecessor,strPath);
cout<<strPath<<endl;
cout<<"路径长度:"<<vDistance[6]<<endl;
boost::dynamic_properties dp;
dp.property("node_id", get(boost::vertex_index, g));
dp.property("label", get(boost::edge_weight, g));
ofstream outf("min.gv");
write_graphviz_dp(outf, g,dp);
return 0;
}
// named parameter version
template <typename Graph, typename P, typename T, typename R>
void dijkstra_shortest_paths(
Graph& g,
typename graph_traits<Graph>::vertex_descriptor s,
const bgl_named_params<P, T, R>& params);
// non-named parameter version
template <typename Graph, typename DijkstraVisitor,
typename PredecessorMap, typename DistanceMap,
typename WeightMap, typename VertexIndexMap, typename CompareFunction, typename CombineFunction,
typename DistInf, typename DistZero, typename ColorMap = default>
void dijkstra_shortest_paths(
const Graph& g,
typename graph_traits<Graph>::vertex_descriptor s,
PredecessorMap predecessor,
DistanceMap distance,
WeightMap weight,
VertexIndexMap index_map,
CompareFunction compare,
CombineFunction combine,
DistInf inf,
DistZero zero,
DijkstraVisitor vis,
ColorMap color = default)
// version that does not initialize the property maps (except for the default color map)
template <class Graph, class DijkstraVisitor,
class PredecessorMap, class DistanceMap,
class WeightMap, class IndexMap, class Compare, class Combine,
class DistZero, class ColorMap>
void dijkstra_shortest_paths_no_init(
const Graph& g,
typename graph_traits<Graph>::vertex_descriptor s,
PredecessorMap predecessor,
DistanceMap distance,
WeightMap weight,
IndexMap index_map,
Compare compare,
Combine combine, DistZero zero,
DijkstraVisitor vis,
ColorMap color = default);