><span class="identifier">size</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">const_node_ptr</span> <span class="special">&amp;</span> header<span class="special">)</span><span class="special">;</span></pre>
<p><span class="bold"><strong>Requires</strong></span>: header is the header node of the tree.</p>
<p><span class="bold"><strong>Effects</strong></span>: Returns the number of nodes above the header.</p>
<p><span class="bold"><strong>Complexity</strong></