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<h2><a name="empty" id="empty">empty</a></h2>
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<p>
Syntax:
</p>
<pre class="c code c++" style="font-family:monospace;">    <span class="co2">#include &lt;queue&gt;</span>
    bool empty<span class="br0">&#40;</span><span class="br0">&#41;</span> <span class="kw4">const</span><span class="sy0">;</span></pre>
<p>
The empty() function returns true if the queue has no elements, false
otherwise.
</p>

<p>
For example, the following code uses empty() as the stopping condition on a
while loop to clear a queue while displaying its contents:
</p>
<pre class="c code c++" style="font-family:monospace;">   queue<span class="sy0">&lt;</span>int<span class="sy0">&gt;</span> q<span class="sy0">;</span>
   <span class="kw1">for</span><span class="br0">&#40;</span> <span class="kw4">int</span> i <span class="sy0">=</span> <span class="nu0">0</span><span class="sy0">;</span> i <span class="sy0">&lt;</span> <span class="nu0">5</span><span class="sy0">;</span> i<span class="sy0">++</span> <span class="br0">&#41;</span> <span class="br0">&#123;</span>
     q.<span class="me1">push</span><span class="br0">&#40;</span>i<span class="br0">&#41;</span><span class="sy0">;</span>
   <span class="br0">&#125;</span>
   <span class="kw1">while</span><span class="br0">&#40;</span> <span class="sy0">!</span>q.<span class="me1">empty</span><span class="br0">&#40;</span><span class="br0">&#41;</span> <span class="br0">&#41;</span> <span class="br0">&#123;</span>
     <a href="http://www.opengroup.org/onlinepubs/009695399/functions/cout.html"><span class="kw3">cout</span></a> <span class="sy0">&lt;&lt;</span> q.<span class="me1">front</span><span class="br0">&#40;</span><span class="br0">&#41;</span> <span class="sy0">&lt;&lt;</span> endl<span class="sy0">;</span>
     q.<span class="me1">pop</span><span class="br0">&#40;</span><span class="br0">&#41;</span><span class="sy0">;</span>
   <span class="br0">&#125;</span></pre>
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