vector<Person> p;
p.reserve(3);
template<typename _Tp, typename _Alloc>
void
vector<_Tp, _Alloc>::
reserve(size_type __n)
{
if (__n > this->max_size())
__throw_length_error(__N("vector::reserve"));
if (this->capacity() < __n)
{
const size_type __old_size = size();
pointer __tmp = _M_allocate_and_copy(__n,
_GLIBCXX_MAKE_MOVE_IF_NOEXCEPT_ITERATOR(this->_M_impl._M_start),
_GLIBCXX_MAKE_MOVE_IF_NOEXCEPT_ITERATOR(this->_M_impl._M_finish));
std::_Destroy(this->_M_impl._M_start, this->_M_impl._M_finish,
_M_get_Tp_allocator());
_M_deallocate(this->_M_impl._M_start,
this->_M_impl._M_end_of_storage
- this->_M_impl._M_start);
this->_M_impl._M_start = __tmp;
this->_M_impl._M_finish = __tmp + __old_size;
this->_M_impl._M_end_of_storage = this->_M_impl._M_start + __n;
}
}
p.resize(3);
void
resize(size_type __new_size)
{
if (__new_size > size())
_M_default_append(__new_size - size());
else if (__new_size < size())
_M_erase_at_end(this->_M_impl._M_start + __new_size);
}
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