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nth_element [C++ Reference]
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<h2><a name="nth_element" id="nth_element">nth_element</a></h2>
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<p>
Syntax:
</p>
<pre class="c code c++" style="font-family:monospace;"> <span class="co2">#include <algorithm></span>
<span class="kw4">void</span> nth_element<span class="br0">(</span> random_access_iterator start<span class="sy0">,</span> random_access_iterator nth<span class="sy0">,</span> random_access_iterator end <span class="br0">)</span><span class="sy0">;</span>
<span class="kw4">void</span> nth_element<span class="br0">(</span> random_access_iterator start<span class="sy0">,</span> random_access_iterator nth<span class="sy0">,</span> random_access_iterator end<span class="sy0">,</span> StrictWeakOrdering cmp <span class="br0">)</span><span class="sy0">;</span></pre>
<p>
The nth_element() function semi-sorts the range of elements defined by
[start,end). It puts the element of the range to the nth position, that would be there, if the entire range
was sorted, and it makes sure that none of the
elements before that element are greater than any of the elements that come
after that element.
</p>
<p>
nth_element() runs in <a href="../../complexity.html" class="wikilink1" title="complexity">linear time</a> on average.
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Related Topics: <a href="../../stl/algorithm/partial_sort.html" class="wikilink1" title="stl:algorithm:partial_sort">partial_sort</a>
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