std::swap(std::priority_queue) - cppreference.com (original) (raw)

| Defined in header | | | | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | ------------------------------------- | | template< class T, class Container, class Compare > void swap( std::priority_queue<T, Container, Compare>& lhs, std::priority_queue<T, Container, Compare>& rhs ); | | (since C++11) (until C++17) | | template< class T, class Container, class Compare > void swap( std::priority_queue<T, Container, Compare>& lhs, std::priority_queue<T, Container, Compare>& rhs ) noexcept(/* see below */); | | (since C++17) (constexpr since C++26) |

Specializes the std::swap algorithm for std::priority_queue. Swaps the contents of lhs and rhs. Calls lhs.swap(rhs).

[edit] Parameters

[edit] Complexity

Same as swapping the underlying containers.

Exceptions

Notes

Although the overloads of std::swap for container adaptors are introduced in C++11, container adaptors can already be swapped by std::swap in C++98. Such calls to std::swap usually have linear time complexity, but better complexity may be provided.

[edit] Example

#include #include #include   int main() { std::priority_queue alice; std::priority_queue bob;   auto print = [](const auto& title, const auto& cont) { std::cout << title << " size=" << cont.size(); std::cout << " top=" << cont.top() << '\n'; };   for (int i = 1; i < 4; ++i) alice.push(i); for (int i = 7; i < 11; ++i) bob.push(i);   // Print state before swap print("Alice:", alice); print("Bobby:", bob);   std::cout << "-- SWAP\n"; std::swap(alice, bob);   // Print state after swap print("Alice:", alice); print("Bobby:", bob); }

Output:

Alice: size=3 top=3 Bobby: size=4 top=10 -- SWAP Alice: size=4 top=10 Bobby: size=3 top=3

[edit] See also

| | swaps the contents (public member function) [edit] | | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |