 as follows</p>
<div class="sourceCode" id="cb4"><pre class="sourceCode stan code-with-copy"><code class="sourceCode stan"><span id="cb4-1"><a href="#cb4-1" aria-hidden="true" tabindex="-1"></a><span class="dt">int</span> add_up(<span class="dt">int</span> a, <span class="dt">int</span> b){</span>
<span id="cb4-2"><a href="#cb4-2" aria-hidden="true" tabindex="-1"></a>  <span class="cf">return</span> a + b;</span>
<span id="cb4-3"><a href="#cb4-3" aria-hidden="true" tabindex="-1"></a>}</span></code><button t