pan class="identifier">increment</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span>
  <span class="keyword">void</span> <a class="link" href="counting_iterator.html#idp53405952-bb"><span class="identifier">decrement</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span>
  <span class="keyword">void</span> <a class="link" href="counting_iterator.html#idp53406800-bb"><span class="identifier">advance</span></a><span