std::partial_sort

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

Sorts some of the elements in the range [first, last) in ascending order. The first ​middle - first​ of these elements are placed in the range [first, middle). The order of equal elements is guaranteed to be preserved. The order of the remaining elements in the range [middle, last) is unspecified. 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	-	the range of elements to sort
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

O(N*log²(N)), where ​N = std::distance(first, last)​ applications of cmp. If additional memory is available, then the complexity is O(N*log(N))

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)