Boost Graph Library: Edge List Class

Boost , ,

edge_list<EdgeIterator, ValueType, DiffType>

The edge_list class is an adaptor that turns a pair of edge iterators into a class that models EdgeListGraph. The value_type of the edge iterator must be a std::pair (or at least have first and second members). The first_type and second_type of the pair must be the same and they will be used for the graph's vertex_descriptor. The ValueType and DiffType template parameters are only needed if your compiler does not support partial specialization. Otherwise they default to the correct types.

Example

Applying the Bellman-Ford shortest paths algorithm to an edge_list.

  enum { u, v, x, y, z, N };
  char name[] = { 'u', 'v', 'x', 'y', 'z' };
  typedef std::pair<int,int> E;
  E edges[] = { 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 weight[] = { -4, 8, 5,
                   -2,
                   9, -3,
                   7, 2,
                   6, 7 };
  typedef boost::edge_list<E*> Graph;
  Graph g(edges, edges + sizeof(edges) / sizeof(E));
    
  std::vector<int> distance(N, std::numeric_limits<short>::max());
  std::vector<int> parent(N,-1);
  
  distance[z] = 0;
  parent[z] = z;
  bool r = boost::bellman_ford_shortest_paths(g, int(N), weight,
                                              distance.begin(),
                                              parent.begin());
  if (r)  
    for (int i = 0; i < N; ++i)
      std::cout << name[i] << ": " << distance[i]
                << " " << name[parent[i]] << std::endl;
  else
    std::cout << "negative cycle" << std::endl;

  u: 2 v
  v: 4 x
  x: 7 z
  y: -2 u
  z: 0 z

Where Defined

Template Parameters

Model of

Associated Types

Member Functions

Non-Member Functions

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