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