</span>
<span class="sd">        DFS code.</span>
<span class="sd">        &quot;&quot;&quot;</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">vMap</span> <span class="o">=</span> <span class="p">{}</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">id</span> <span class="o">=</span> <span class="nb">id</span>
        <span class="k">if</span> <span class="n">vMap</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">