 starting vertex.  The d output records the
            distance, and the dt output records the step of the algorithm when the breadth first search saw the node.
         </p><pre class="codeinput">[d dt] = bfs(A,2);
<span class="comment">% draw the graph where the label is the "discovery time" of the vertex.</span>
figure(1); clf; graph_draw(A,xy,<span class="string">'labels'</span>,num2str(dt));
</pre><img vspace="5" hspace="5" src="demo_04.png" alt=""> <p>Notice how the algorithm visits all vertices one 