C++

Reference

<queue>

queue

public member function
<queue>

std::queue::swap

void swap (queue& x) noexcept(/*see below*/);
Swap contents
Exchanges the contents of the container adaptor (*this) by those of x.

This member function calls the non-member function swap (unqualified) to swap the underlying containers.

The noexcept specifier matches the swap operation on the underlying container.

Parameters

x
Another queue container adaptor of the same type (i.e., instantiated with the same template parameters, T and Container). Sizes may differ.

Return value

none

Example

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// queue::swap
#include <iostream>       // std::cout
#include <queue>          // std::queue

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

  foo.swap(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 *this and x are modified.

Exception safety

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

See also

swap (queue)
Exchange contents of queues (public member function)
swap
Exchange values of two objects (function template)