 </span><span class="n">std</span><span class="o">::</span><span class="n">string</span><span class="o">&amp;</span><span class="w"> </span><span class="n">node</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
<span class="w">  </span><span class="n">printf</span><span class="p">(</span><span class="s">&quot;f2(%s)</span><span class="se">\n</span><span class="s">&quot;</span><span class="p">,</span><span class="w"> </span><span class="n">node</span><span class="p">.</span><span