multiset::get_allocator
用于返回的对象分配程序的复制构造多集。
allocator_type get_allocator( ) const;
返回值
多集使用的分配器。
备注
多个设置类的分配器指定类如何管理存储。 默认分配程序都附有 STL 容器类用于大多数编程的需要即可。 拥有分配编写和使用程序类是高级 C++ 主题。
示例
// multiset_get_allocator.cpp
// compile with: /EHsc
#include <set>
#include <iostream>
int main( )
{
using namespace std;
multiset <int>::allocator_type ms1_Alloc;
multiset <int>::allocator_type ms2_Alloc;
multiset <double>::allocator_type ms3_Alloc;
multiset <int>::allocator_type ms4_Alloc;
// The following lines declare objects
// that use the default allocator.
multiset <int> ms1;
multiset <int, allocator<int> > ms2;
multiset <double, allocator<double> > ms3;
cout << "The number of integers that can be allocated"
<< endl << "before free memory is exhausted: "
<< ms2.max_size( ) << "." << endl;
cout << "The number of doubles that can be allocated"
<< endl << "before free memory is exhausted: "
<< ms3.max_size( ) << "." << endl;
// The following lines create a multiset ms4
// with the allocator of multiset ms1
ms1_Alloc = ms1.get_allocator( );
multiset <int> ms4( less<int>( ), ms1_Alloc );
ms4_Alloc = ms4.get_allocator( );
// Two allocators are interchangeable if
// storage allocated from each can be
// deallocated with the other
if( ms1_Alloc == ms4_Alloc )
{
cout << "Allocators are interchangeable."
<< endl;
}
else
{
cout << "Allocators are not interchangeable."
<< endl;
}
}
示例输出
将生成下面关于x86的输出。
The number of integers that can be allocated
before free memory is exhausted: 1073741823.
The number of doubles that can be allocated
before free memory is exhausted: 536870911.
Allocators are interchangeable.
要求
标头: <set>
命名空间: std