 class="special">+</span> <span class="special">(</span><span class="identifier">h</span> <span class="special">*</span> <span class="identifier">sum</span><span class="special">);</span>

      <span class="keyword">const</span> <span class="identifier">value_type</span> <span class="identifier">ratio</span>     <span class="special">=</span> <span class="identifier">I0</span> <span class="special">/</span> <span class="identifier">I</span><span class="special">;</span>
      <span class="keyword">const</s