ong>Requires</strong></span>: 'header' is the header node of a tree.</p>
<p><span class="bold"><strong>Effects</strong></span>: Returns the header of the tree.</p>
<p><span class="bold"><strong>Complexity</strong></span>: Constant time.</p>
<p><span class="bold"><strong>Throws</strong></span>: Nothing. </p>
</li>
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<pre class="literallayout"><span class="keyword">static</span> <span class="keyword">void</span> <a name="idp56858544-bb"></a><span class="identifier">swap_tree</span><span cl