span>
        <span class="k">return</span> <span class="n">x</span><span class="o">+</span><span class="n">y</span><span class="p">;</span>
    <span class="p">}</span>
<span class="p">};</span>

<span class="kt">int</span> <span class="nf">main</span><span class="p">()</span> <span class="p">{</span>
    <span class="n">assert</span><span class="p">(</span><span class="mi">3</span> <span class="o">==</span> <span class="n">partial</span><span class="p">(</span><span class="n">sum</span><span class="p">())