:add-edge"><tt>add_edge()</tt></a>
function of the <a href="MutableGraph.html">MutableGraph</a> interface (which <tt>adjacency_list</tt>
implements). We use the array of pairs <tt>edge_array</tt> merely as a
convenient way to explicitly create the edges for this example.
<p>&nbsp;
<pre>
  #include &lt;iostream&gt;                  // for std::cout
  #include &lt;utility&gt;                   // for std::pair
  #include &lt;algorithm&gt;                 // for std::for_each
  #include &lt;boost/graph/graph_t