lt;&lt; &quot;vertices(g) = &quot;;
    typedef graph_traits&lt;Graph&gt;::vertex_iterator vertex_iter;
    std::pair&lt;vertex_iter, vertex_iter&gt; vp;
    for (vp = vertices(g); vp.first != vp.second; ++vp.first) {
      Vertex v = *vp.first;
      std::cout &lt;&lt; index[v] &lt;&lt;  &quot; &quot;;
    }
    std::cout &lt;&lt; std::endl;
    // ...
    return 0;
  }
</pre>
The output is:
<pre>
  vertices(g) = 0 1 2 3 4
</pre>
<p>&nbsp;
<h2>Accessing the Edge Set</h2>
<p>The set of edges for a graph can