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此 API 已过时。另一种方法是 unordered_multimap Class。 |
从指定的位置移除元素或元素的大小 hash_multimap 的或移除与指定的键的元素。
iterator erase(
iterator _Where
);
iterator erase(
iterator _First,
iterator _Last
);
size_type erase(
const key_type& _Key
);
参数
_Where
从 hash_multimap 要移除的元素的位置。_First
从 hash_multimap 移除的第一个元素的位置。_Last
在从 hash_multimap 移除的最后一个元素之外标识。_Key
从 hash_multimap 要移除的元素的键。
返回值
对于前两个成员函数、指定保持在所有元素外的第一个元素中移除一双向迭代器或对 hash_multimap 的末尾的指针,如果不存在这样的元素。
为第三个成员函数,返回从 hash_multimap 中移除了元素的数目。
备注
成员函数从不引发异常。
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
当编译此示例与 /Wp64 标记或在 64 位平台时,警告的编译器 C4267 将生成。有关此警告的更多信息,请参见 编译器警告(等级 3)C4267。
// hash_multimap_erase.cpp
// compile with: /EHsc
#include <hash_map>
#include <iostream>
int main()
{
using namespace std;
using namespace stdext;
hash_multimap<int, int> hm1, hm2, hm3;
hash_multimap<int, int> :: iterator pIter, Iter1, Iter2;
int i;
hash_multimap<int, int>::size_type n;
typedef pair<int, int> Int_Pair;
for (i = 1; i < 5; i++)
{
hm1.insert(Int_Pair (i, i) );
hm2.insert(Int_Pair (i, i*i) );
hm3.insert(Int_Pair (i, i-1) );
}
// The 1st member function removes an element at a given position
Iter1 = ++hm1.begin();
hm1.erase(Iter1);
cout << "After the 2nd element is deleted, "
<< "the hash_multimap hm1 is:";
for (pIter = hm1.begin(); pIter != hm1.end(); pIter++)
cout << " " << pIter -> second;
cout << "." << endl;
// The 2nd member function removes elements
// in the range [_First, _Last)
Iter1 = ++hm2.begin();
Iter2 = --hm2.end();
hm2.erase(Iter1, Iter2);
cout << "After the middle two elements are deleted, "
<< "the hash_multimap hm2 is:";
for (pIter = hm2.begin(); pIter != hm2.end(); pIter++)
cout << " " << pIter -> second;
cout << "." << endl;
// The 3rd member function removes elements with a given _Key
hm3.insert(Int_Pair (2, 5));
n = hm3.erase(2);
cout << "After the element with a key of 2 is deleted,\n"
<< " the hash_multimap hm3 is:";
for (pIter = hm3.begin(); pIter != hm3.end(); pIter++)
cout << " " << pIter -> second;
cout << "." << endl;
// The 3rd member function returns the number of elements removed
cout << "The number of elements removed from hm3 is: "
<< n << "." << endl;
// The dereferenced iterator can also be used to specify a key
Iter1 = ++hm3.begin();
hm3.erase(Iter1);
cout << "After another element with a key equal to that of the"
<< endl;
cout << " 2nd element is deleted, "
<< "the hash_multimap hm3 is:";
for (pIter = hm3.begin(); pIter != hm3.end(); pIter++)
cout << " " << pIter -> second;
cout << "." << endl;
}
要求
标头: <hash_map>
命名空间: stdext