public member function
<list>

std::list::clear

void clear();
void clear() noexcept;
Clear content
Removes all elements from the list container (which are destroyed), and leaving the container with a size of 0.

Parameters

none

Return value

none

Example

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// clearing lists
#include <iostream>
#include <list>

int main ()
{
  std::list<int> mylist;
  std::list<int>::iterator it;

  mylist.push_back (100);
  mylist.push_back (200);
  mylist.push_back (300);

  std::cout << "mylist contains:";
  for (it=mylist.begin(); it!=mylist.end(); ++it)
    std::cout << ' ' << *it;
  std::cout << '\n';

  mylist.clear();
  mylist.push_back (1101);
  mylist.push_back (2202);

  std::cout << "mylist contains:";
  for (it=mylist.begin(); it!=mylist.end(); ++it)
    std::cout << ' ' << *it;
  std::cout << '\n';

  return 0;
}


Output:
mylist contains: 100 200 300
mylist contains: 1101 2202

Complexity

Linear in list::size (destructions).

Iterator validity

All iterators, references and pointers related to this container are invalidated, except the end iterators.

Data races

The container is modified.
All contained elements are modified.

Exception safety

No-throw guarantee: this member function never throws exceptions.

See also

  • 1793521592 2018-02-23
  • 2864591591 2018-02-23
  • 6167231590 2018-02-23
  • 3669201589 2018-02-23
  • 7946381588 2018-02-23
  • 8957701587 2018-02-23
  • 3891941586 2018-02-23
  • 6039851585 2018-02-23
  • 2573991584 2018-02-23
  • 7728781583 2018-02-23
  • 3731582 2018-02-23
  • 1007451581 2018-02-22
  • 8908121580 2018-02-22
  • 141161579 2018-02-22
  • 9421578 2018-02-22
  • 2826901577 2018-02-22
  • 3647361576 2018-02-22
  • 5717551575 2018-02-22
  • 523811574 2018-02-22
  • 6439871573 2018-02-22