std::partition_point
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<tbody> </tbody> template< class ForwardIt, class UnaryPredicate > ForwardIt partition_point( ForwardIt first, ForwardIt last, UnaryPredicate p); |
(1) | ( C++11) |
( std::partition)
[first, last) , , p last , p.:
Examines the partitioned (as if by std::partition) range
[first, last) and locates the end of the first partition, that is, the first element that does not satisfy p or last if last if all elements satisfy p.| first, last | ||
| p | , true , . :
| |
-ForwardIt ForwardIterator.
| ||
[first, last) last, p.:
The iterator past the end of the first partition within
[first, last) or last if all elements satisfy p.#include <algorithm>
#include <array>
#include <iostream>
#include <iterator>
int main()
{
std::array<int, 9> v = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
auto is_even = [](int i){ return i % 2 == 0; };
std::partition(v.begin(), v.end(), is_even);
auto p = std::partition_point(v.begin(), v.end(), is_even);
std::cout << "Before partition:\n ";
std::copy(v.begin(), p, std::ostream_iterator<int>(std::cout, " "));
std::cout << "\nAfter partition:\n ";
std::copy(p, v.end(), std::ostream_iterator<int>(std::cout, " "));
}
:
Before partition:
8 2 6 4
After partition:
5 3 7 1 9
.
(C++11) |
, ( ) |