std::nth_element

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Defined in header <algorithm>
​template< class RandomAccessIterator > void nth_element( RandomAccessIterator first,                   RandomAccessIterator nth,                   RandomAccessIterator last );​	(1)
​template< class RandomAccessIterator, class Compare > void nth_element( RandomAccessIterator first,                   RandomAccessIterator nth,                   RandomAccessIterator last, Compare comp );​	(2)

Partially sorts the range [first, last) in ascending order so that all elements in the range [first, nth) are less than those in the range [nth, last). The first version uses ​operator<​ to compare the elements, the second version uses the given comparison function comp.

Contents 1 Parameters 2 Return value 3 Complexity 4 Example 5 See also

Parameters

first, last	-	random access iterators defining the range sort
nth	-	random access iterator defining the sort partition point
comp	-	comparison function which returns ​​true​ if the first argument is less than the second. The signature of the comparison function should be equivalent to the following: ​bool cmp(const Type1 &a, const Type2 &b);​ The signature does not need to have ​const &​, but the function must not modify the objects passed to it. The types ​Type1​ and ​Type2​ must be such that an object of type ​RandomAccessIterator​ can be dereferenced and then implicitly converted to both of them. ​

Return value

(none)

Complexity

Linear in std::distance(first, last) on average.

Example

This section is incomplete

See also

partial_sort_copy	copies and partially sorts a range of elements (function template)
stable_sort	sorts a range of elements while preserving order between equal elements (function template)
sort	sorts a range into ascending order (function template)