Делает станд.:: вектор pop_back () изменяет способность вектора?
Этот вопрос решает очень связанную проблему, которая может помочь сетевые ресурсы использования в powershell.
4 ответа
No. The only way to shrink a vector's capacity is the swap trick
template< typename T, class Allocator >
void shrink_capacity(std::vector<T,Allocator>& v)
{
std::vector<T,Allocator>(v.begin(),v.end()).swap(v);
}
and even that isn't guaranteed to work according to the standard. (Although it's hard to imagine an implementation where it wouldn't work.)
As far as I know, the next version of the C++ standard (what used to be C++0x, but now became C++1x) will have std::vector<>::shrink_to_fit().
No. pop_back() will not shrink the capacity of vector. use
std::vector instead.
NO. Same as push_back , pop_back won't impact the capacity(). They just impact the size().
EDIT:
I should have said push_back won't change the capacity when the v.size() < v.capacity().
pop_XXX никогда не изменит емкость. push_XXX может изменить емкость, если вы попытаетесь протолкнуть больше материала, чем позволяет емкость.