line"> </div>
<div class="line">    <span class="comment">// iteration</span></div>
<div class="line">    <span class="keywordflow">for</span> (<span class="keyword">auto</span> it = a.begin(); it &lt; a.end(); ++it)</div>
<div class="line">    {</div>
<div class="line">        std::cout &lt;&lt; *it &lt;&lt; <span class="stringliteral">&quot; &quot;</span>;</div>
<div class="line">    }</div>
<div class="line">    std::cout &lt;&lt; std::endl;</div>
<div class="line"> </div>
<div class="line">    <span cla