public member function

std::list::swap

<list>
void swap ( list<T,Allocator>& lst );
Swap content
Exchanges the content of the container by the content of lst, which is another list object containing elements of the same type. Sizes may differ.

After the call to this member function, the elements in this container are those which were in lst before the call, and the elements of lst are those which were in this. All iterators, references and pointers remain valid for the swapped objects.

Notice that a global algorithm function exists with this same name, swap, and the same behavior.

Parameters

lst
Another list container of the same type as this whose content is swapped with that of this container.

Return value

none

Example

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// swap lists
#include <iostream>
#include <list>
using namespace std;

int main ()
{
  list<int> first (3,100);   // three ints with a value of 100
  list<int> second (5,200);  // five ints with a value of 200
  list<int>::iterator it;

  first.swap(second);

  cout << "first contains:";
  for (it=first.begin(); it!=first.end(); it++) cout << " " << *it;

  cout << "\nsecond contains:";
  for (it=second.begin(); it!=second.end(); it++) cout << " " << *it;

  cout << endl;

  return 0;
}


Output:
first contains: 200 200 200 200 200 
second contains: 100 100 100

Complexity

Constant.

See also

swap
Exchange values of two objects (function template)

C++