urn</span> <span class="identifier">r</span><span class="special">;</span>
<span class="special">}</span>
</pre>
                </td>
<td>
                </td>
</tr>
<tr>
<td>
                  <p>
                    <code class="computeroutput"><span class="identifier">a</span> <span class="special">+</span>
                    <span class="identifier">n</span></code>, <code class="computeroutput"><span class="identifier">n</span>
                    <span class="special">+</span> <span class="identifie