public member function
<set>

std::multiset::clear

void clear();
void clear() noexcept;
Clear content
Removes all elements from the multiset container (which are destroyed), leaving the container with a size of0.

参数



返回值



示例

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// multiset::clear
#include <iostream>
#include <set>

int main ()
{
  std::multiset<int> mymultiset;

  mymultiset.insert (11);
  mymultiset.insert (42);
  mymultiset.insert (11);

  std::cout << "mymultiset contains:";
  for (std::multiset<int>::iterator it=mymultiset.begin(); it!=mymultiset.end(); ++it)
    std::cout << ' ' << *it;
  std::cout << '\n';

  mymultiset.clear();
  mymultiset.insert (200);
  mymultiset.insert (100);

  std::cout << "mymultiset contains:";
  for (std::multiset<int>::iterator it=mymultiset.begin(); it!=mymultiset.end(); ++it)
    std::cout << ' ' << *it;

  std::cout << '\n';

  return 0;
}

输出
mymultiset contains: 11 11 42
myset contains: 100 200


复杂度

Linear in size (destructions).

迭代器有效性

所有与该容器相关的迭代器、指针和引用都将失效。

数据竞争

The container is modified.
所有包含的元素都被修改。

异常安全

无异常保证:此成员函数从不抛出异常。

另见