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此 API 已过时。另一种方法是 unordered_multimap Class。 |
返回解决的迭代器已取消的 hash_multimap 的第一个元素。
const_reverse_iterator rbegin( ) const;
reverse_iterator rbegin( );
返回值
解决活动反向双向的迭代器解决在一是相反的 hash_multimap 的第一个元素或什么是在 unreversed hash_multimap 的最后一个元素。
备注
正 启动 使用 hash_multimap,rbegin 使用具有是相反的 hash_multimap。
如果 rbegin 的返回值赋给 const_reverse_iterator,则不能修改 hash_multimap 对象。如果 rbegin 的返回值赋给 reverse_iterator,则可以修改 hash_multimap 对象。
rbegin 可用于通过 hash_multimap 向后重复。
在 Visual C++ .NET 2003 中,<hash_map> 和 <hash_set> 标头文件的成员中不再标准,命名空间,而是将 stdext 命名空间。有关更多信息,请参见 stdext 命名空间。
示例
// hash_multimap_rbegin.cpp
// compile with: /EHsc
#include <hash_map>
#include <iostream>
int main( )
{
using namespace std;
using namespace stdext;
hash_multimap <int, int> hm1;
hash_multimap <int, int> :: iterator hm1_Iter;
hash_multimap <int, int> :: reverse_iterator hm1_rIter;
hash_multimap <int, int> :: const_reverse_iterator hm1_crIter;
typedef pair <int, int> Int_Pair;
hm1.insert ( Int_Pair ( 1, 10 ) );
hm1.insert ( Int_Pair ( 2, 20 ) );
hm1.insert ( Int_Pair ( 3, 30 ) );
hm1_rIter = hm1.rbegin( );
cout << "The first element of the reversed hash_multimap hm1 is "
<< hm1_rIter -> first << "." << endl;
// begin can be used to start an iteration
// through a hash_multimap in a forward order
cout << "The hash_multimap is: ";
for ( hm1_Iter = hm1.begin( ) ; hm1_Iter != hm1.end( ); hm1_Iter++)
cout << hm1_Iter -> first << " ";
cout << "." << endl;
// rbegin can be used to start an iteration
// through a hash_multimap in a reverse order
cout << "The reversed hash_multimap is: ";
for ( hm1_rIter = hm1.rbegin( ) ; hm1_rIter != hm1.rend( ); hm1_rIter++)
cout << hm1_rIter -> first << " ";
cout << "." << endl;
// A hash_multimap element can be erased by dereferencing its key
hm1_rIter = hm1.rbegin( );
hm1.erase ( hm1_rIter -> first );
hm1_rIter = hm1.rbegin( );
cout << "After the erasure, the first element"
<< "\n in the reversed hash_multimap is "
<< hm1_rIter -> first << "." << endl;
}
要求
标头: <hash_map>
命名空间: stdext