hash_set::get_allocator
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這個 API 已經過時。這個選項是 unordered_set Class。 |
傳回用來配置器物件複本建構 hash_set。
Allocator get_allocator( ) const;
傳回值
hash_set 用來配置器處理記憶體,是樣板參數 Allocator。
如需 Allocator資訊,請參閱 hash_set Class 主題的<備註>一節。
備註
hash_set 類別的配置器指定類別如何處理儲存區。預設配置器提供 STL 容器類別的大部分程式的需求就已足夠。撰寫和使用的配置器類別是進階 C++ 主題。
在 Visual C++ .NET Pocket PC, <hash_map> 和 <hash_set> 標頭檔 (Header File) 的成員不在 std 命名空間,,而是移至 stdext 命名空間。如需詳細資訊,請參閱 stdext 命名空間。
範例
// hash_set_get_allocator.cpp
// compile with: /EHsc
#include <hash_set>
#include <iostream>
int main( )
{
using namespace std;
using namespace stdext;
// The following lines declare objects
// that use the default allocator.
hash_set <int, hash_compare <int, less<int> > > hs1;
hash_set <int, hash_compare <int, greater<int> > > hs2;
hash_set <double, hash_compare <double,
less<double> >, allocator<double> > hs3;
hash_set <int, hash_compare <int,
greater<int> > >::allocator_type hs2_Alloc;
hash_set <double>::allocator_type hs3_Alloc;
hs2_Alloc = hs2.get_allocator( );
cout << "The number of integers that can be allocated"
<< endl << "before free memory is exhausted: "
<< hs1.max_size( ) << "." << endl;
cout << "The number of doubles that can be allocated"
<< endl << "before free memory is exhausted: "
<< hs3.max_size( ) << "." << endl;
// The following lines create a hash_set hs4
// with the allocator of hash_set hs1.
hash_set <int>::allocator_type hs4_Alloc;
hash_set <int> hs4;
hs4_Alloc = hs2.get_allocator( );
// Two allocators are interchangeable if
// storage allocated from each can be
// deallocated by the other
if( hs2_Alloc == hs4_Alloc )
{
cout << "The allocators are interchangeable."
<< endl;
}
else
{
cout << "The allocators are not interchangeable."
<< endl;
}
}
範例輸出
下列輸出是 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.
需求
標題: <hash_set>
命名空間: stdext