6.8 KiB
[priqueue.overview]
23 Containers library [containers]
23.6 Container adaptors [container.adaptors]
23.6.4 Class template priority_queue [priority.queue]
23.6.4.1 Overview [priqueue.overview]
Any sequence container with random access iterator and supporting operationsfront(),push_back() andpop_back() can be used to instantiatepriority_queue.
In particular, and can be used.
Instantiatingpriority_queue also involves supplying a function or function object for making priority comparisons; the library assumes that the function or function object defines a strict weak ordering.
namespace std {template<class T, class Container = vector, class Compare = less>class priority_queue {public:using value_type = typename Container::value_type; using reference = typename Container::reference; using const_reference = typename Container::const_reference; using size_type = typename Container::size_type; using container_type = Container; using value_compare = Compare; protected: Container c; Compare comp; public:constexpr priority_queue() : priority_queue(Compare()) {}constexpr explicit priority_queue(const Compare& x) : priority_queue(x, Container()) {}constexpr priority_queue(const Compare& x, const Container&); constexpr priority_queue(const Compare& x, Container&&); templateconstexpr priority_queue(InputIterator first, InputIterator last, const Compare& x = Compare()); templateconstexpr priority_queue(InputIterator first, InputIterator last, const Compare& x, const Container&); templateconstexpr priority_queue(InputIterator first, InputIterator last, const Compare& x, Container&&); template<container-compatible-range R>constexpr priority_queue(from_range_t, R&& rg, const Compare& x = Compare()); template constexpr explicit priority_queue(const Alloc&); template constexpr priority_queue(const Compare&, const Alloc&); templateconstexpr priority_queue(const Compare&, const Container&, const Alloc&); template constexpr priority_queue(const Compare&, Container&&, const Alloc&); template constexpr priority_queue(const priority_queue&, const Alloc&); template constexpr priority_queue(priority_queue&&, const Alloc&); template<class InputIterator, class Alloc>constexpr priority_queue(InputIterator, InputIterator, const Alloc&); template<class InputIterator, class Alloc>constexpr priority_queue(InputIterator, InputIterator, const Compare&, const Alloc&); template<class InputIterator, class Alloc>constexpr priority_queue(InputIterator, InputIterator, const Compare&, const Container&, const Alloc&); template<class InputIterator, class Alloc>constexpr priority_queue(InputIterator, InputIterator, const Compare&, Container&&, const Alloc&); template<container-compatible-range R, class Alloc>constexpr priority_queue(from_range_t, R&& rg, const Compare&, const Alloc&); template<container-compatible-range R, class Alloc>constexpr priority_queue(from_range_t, R&& rg, const Alloc&); constexpr bool empty() const { return c.empty(); }constexpr size_type size() const { return c.size(); }constexpr const_reference top() const { return c.front(); }constexpr void push(const value_type& x); constexpr void push(value_type&& x); template<container-compatible-range R>constexpr void push_range(R&& rg); template<class... Args> constexpr void emplace(Args&&... args); constexpr void pop(); constexpr void swap(priority_queue& q)noexcept(is_nothrow_swappable_v && is_nothrow_swappable_v){ using std::swap; swap(c, q.c); swap(comp, q.comp); }}; template<class Compare, class Container> priority_queue(Compare, Container)-> priority_queue<typename Container::value_type, Container, Compare>; template<class InputIterator, class Compare = less<iter-value-type>, class Container = vector<iter-value-type>> priority_queue(InputIterator, InputIterator, Compare = Compare(), Container = Container())-> priority_queue<iter-value-type, Container, Compare>; template<ranges::input_range R, class Compare = less<ranges::range_value_t>> priority_queue(from_range_t, R&&, Compare = Compare())-> priority_queue<ranges::range_value_t, vector<ranges::range_value_t>, Compare>; template<class Compare, class Container, class Allocator> priority_queue(Compare, Container, Allocator)-> priority_queue<typename Container::value_type, Container, Compare>; template<class InputIterator, class Allocator> priority_queue(InputIterator, InputIterator, Allocator)-> priority_queue<iter-value-type, vector<iter-value-type, Allocator>, less<iter-value-type>>; template<class InputIterator, class Compare, class Allocator> priority_queue(InputIterator, InputIterator, Compare, Allocator)-> priority_queue<iter-value-type, vector<iter-value-type, Allocator>, Compare>; template<class InputIterator, class Compare, class Container, class Allocator> priority_queue(InputIterator, InputIterator, Compare, Container, Allocator)-> priority_queue<typename Container::value_type, Container, Compare>; template<ranges::input_range R, class Compare, class Allocator> priority_queue(from_range_t, R&&, Compare, Allocator)-> priority_queue<ranges::range_value_t, vector<ranges::range_value_t, Allocator>, Compare>; template<ranges::input_range R, class Allocator> priority_queue(from_range_t, R&&, Allocator)-> priority_queue<ranges::range_value_t, vector<ranges::range_value_t, Allocator>>; // no equality is providedtemplate<class T, class Container, class Compare, class Alloc>struct uses_allocator<priority_queue<T, Container, Compare>, Alloc>: uses_allocator<Container, Alloc>::type { };}