set::get_allocator

返回用于的分配器对象的复制构造集。

allocator_type get_allocator( ) const;

返回值

使用的分配器组托管内存，是模板参数 Allocator。

有关 Allocator的更多信息，请参见 set Class 主题的"备注"节。

备注

设置的选件类的分配器指定选件类如何管理存储。默认分配程序提供了STL容器选件类对于大多数编程的需要就足够了。编写和使用您的分配器选件类是高级C++主题。

示例

// set_get_allocator.cpp
// compile with: /EHsc
#include <set>
#include <iostream>

int main( )
{
   using namespace std;
   set <int>::allocator_type s1_Alloc;
   set <int>::allocator_type s2_Alloc;
   set <double>::allocator_type s3_Alloc;
   set <int>::allocator_type s4_Alloc;

   // The following lines declare objects
   // that use the default allocator.
   set <int> s1;
   set <int, allocator<int> > s2;
   set <double, allocator<double> > s3;

   s1_Alloc = s1.get_allocator( );
   s2_Alloc = s2.get_allocator( );
   s3_Alloc = s3.get_allocator( );

   cout << "The number of integers that can be allocated"
        << endl << "before free memory is exhausted: "
        << s2.max_size( ) << "." << endl;

   cout << "\nThe number of doubles that can be allocated"
        << endl << "before free memory is exhausted: "
        << s3.max_size( ) <<  "." << endl;

   // The following line creates a set s4
   // with the allocator of multiset s1.
   set <int> s4( less<int>( ), s1_Alloc );

   s4_Alloc = s4.get_allocator( );

   // Two allocators are interchangeable if
   // storage allocated from each can be
   // deallocated by the other
   if( s1_Alloc == s4_Alloc )
   {
      cout << "\nThe allocators are interchangeable."
           << endl;
   }
   else
   {
      cout << "\nThe allocators are not interchangeable."
           << endl;
   }
}

示例输出

下面的输出是针对x86。

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.

The allocators are interchangeable.

要求

标头: <set>

命名空间: std

请参见

参考

set Class

标准模板库