2</span> <span class="special">+</span> <span class="special">(</span><span class="number">3</span> <span class="special">+</span> <span class="special">(</span><span class="number">4</span> <span class="special">+</span> <span class="number">5</span><span class="special">))))</span>
</pre>
<p>
      Certainly we have modified the original EBNF syntax. This is done to conform
      to C++ syntax rules. Most notably we see the abundance of shift &gt;&gt; operators.
      Since there are no 'empty' operators 