public member function
<queue>

std::swap (queue)

template <class T, class Container>
  void swap (queue<T,Container>& x, queue<T,Container>& y) noexcept(noexcept(x.swap(y)));
Exchange contents of queues
Exchanges the contents of x and y.

Parameters

x,y
queue containers of the same type. Size may differ.

Return value

none

Example

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// swap queues
#include <iostream>       // std::cout
#include <queue>          // std::queue, std::swap(queue)

int main ()
{
  std::queue<int> foo,bar;
  foo.push (10); foo.push(20); foo.push(30);
  bar.push (111); bar.push(222);

  swap(foo,bar);

  std::cout << "size of foo: " << foo.size() << '\n';
  std::cout << "size of bar: " << bar.size() << '\n';

  return 0;
}


Output:

size of foo: 2
size of bar: 3

Complexity

Constant.

Data races

Both container adaptors, x and y, are modified.

Exception safety

Provides the same level of guarantees as the operation performed on the underlying container objects.

See also