标准库头文件 <queue>
来自cppreference.com
此头文件是容器库的一部分。
包含 | |
(C++20) |
三路比较运算符支持 |
(C++11) |
std::initializer_list 类模板 |
类 | |
适配一个容器以提供队列(FIFO 数据结构) (类模板) | |
适配一个容器以提供优先级队列 (类模板) | |
特化 std::uses_allocator 类型特征 (类模板特化) | |
特化 std::uses_allocator 类型特征 (类模板特化) | |
函数 | |
按照字典顺序比较 queue 中的值 (函数模板) | |
(C++11) |
特化 std::swap 算法 (函数模板) |
特化 std::swap 算法 (函数模板) |
概要
#include <compare> #include <initializer_list> namespace std { template<class T, class Container = deque<T>> class queue; template<class T, class Container> bool operator==(const queue<T, Container>& x, const queue<T, Container>& y); template<class T, class Container> bool operator!=(const queue<T, Container>& x, const queue<T, Container>& y); template<class T, class Container> bool operator< (const queue<T, Container>& x, const queue<T, Container>& y); template<class T, class Container> bool operator> (const queue<T, Container>& x, const queue<T, Container>& y); template<class T, class Container> bool operator<=(const queue<T, Container>& x, const queue<T, Container>& y); template<class T, class Container> bool operator>=(const queue<T, Container>& x, const queue<T, Container>& y); template<class T, three_way_comparable Container> compare_three_way_result_t<Container> operator<=>(const queue<T, Container>& x, const queue<T, Container>& y); template<class T, class Container> void swap(queue<T, Container>& x, queue<T, Container>& y) noexcept(noexcept(x.swap(y))); template<class T, class Container, class Alloc> struct uses_allocator<queue<T, Container>, Alloc>; template<class T, class Container = vector<T>, class Compare = less<typename Container::value_type>> class priority_queue; template<class T, class Container, class Compare> void swap(priority_queue<T, Container, Compare>& x, priority_queue<T, Container, Compare>& y) noexcept(noexcept(x.swap(y))); template<class T, class Container, class Compare, class Alloc> struct uses_allocator<priority_queue<T, Container, Compare>, Alloc>; }
类模板 std::queue
namespace std { template<class T, class Container = deque<T>> class 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; protected: Container c; public: queue() : queue(Container()) {} explicit queue(const Container&); explicit queue(Container&&); template<class InputIt> queue(InputIt first, InputIt last); template<class Alloc> explicit queue(const Alloc&); template<class Alloc> queue(const Container&, const Alloc&); template<class Alloc> queue(Container&&, const Alloc&); template<class Alloc> queue(const queue&, const Alloc&); template<class Alloc> queue(queue&&, const Alloc&); template<class InputIt, class Alloc> queue(InputIt first, InputIt last, const Alloc&); [[nodiscard]] bool empty() const { return c.empty(); } size_type size() const { return c.size(); } reference front() { return c.front(); } const_reference front() const { return c.front(); } reference back() { return c.back(); } const_reference back() const { return c.back(); } void push(const value_type& x) { c.push_back(x); } void push(value_type&& x) { c.push_back(std::move(x)); } template<class... Args> decltype(auto) emplace(Args&&... args) { return c.emplace_back(std::forward<Args>(args)...); } void pop() { c.pop_front(); } void swap(queue& q) noexcept(is_nothrow_swappable_v<Container>) { using std::swap; swap(c, q.c); } }; template<class Container> queue(Container) -> queue<typename Container::value_type, Container>; template<class InputIt> queue(InputIt, InputIt) -> queue</*iter-value-type*/<InputIt>>; template<class Container, class Allocator> queue(Container, Allocator) -> queue<typename Container::value_type, Container>; template<class InputIt, class Allocator> queue(InputIt, InputIt, Allocator) -> queue</*iter-value-type*/<InputIt>, deque</*iter-value-type*/<InputIt>, Allocator>>; template<class T, class Container, class Alloc> struct uses_allocator<queue<T, Container>, Alloc> : uses_allocator<Container, Alloc>::type { }; }
类模板 std::priority_queue
namespace std { template<class T, class Container = vector<T>, class Compare = less<typename Container::value_type>> 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: priority_queue() : priority_queue(Compare()) {} explicit priority_queue(const Compare& x) : priority_queue(x, Container()) {} priority_queue(const Compare& x, const Container&); priority_queue(const Compare& x, Container&&); template<class InputIt> priority_queue(InputIt first, InputIt last, const Compare& x = Compare()); template<class InputIt> priority_queue(InputIt first, InputIt last, const Compare& x, const Container&); template<class InputIt> priority_queue(InputIt first, InputIt last, const Compare& x, Container&&); template<class Alloc> explicit priority_queue(const Alloc&); template<class Alloc> priority_queue(const Compare&, const Alloc&); template<class Alloc> priority_queue(const Compare&, const Container&, const Alloc&); template<class Alloc> priority_queue(const Compare&, Container&&, const Alloc&); template<class Alloc> priority_queue(const priority_queue&, const Alloc&); template<class Alloc> priority_queue(priority_queue&&, const Alloc&); template<class InputIt, class Alloc> priority_queue(InputIt, InputIt, const Alloc&); template<class InputIt, class Alloc> priority_queue(InputIt, InputIt, const Compare&, const Alloc&); template<class InputIt, class Alloc> priority_queue(InputIt, InputIt, const Compare&, const Container&, const Alloc&); template<class InputIt, class Alloc> priority_queue(InputIt, InputIt, const Compare&, Container&&, const Alloc&); [[nodiscard]] bool empty() const { return c.empty(); } size_type size() const { return c.size(); } const_reference top() const { return c.front(); } void push(const value_type& x); void push(value_type&& x); template<class... Args> void emplace(Args&&... args); void pop(); void swap(priority_queue& q) noexcept(is_nothrow_swappable_v<Container> && is_nothrow_swappable_v<Compare>) { 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 InputIt, class Compare = less</*iter-value-type*/<InputIt>>, class Container = vector</*iter-value-type*/<InputIt>>> priority_queue(InputIt, InputIt, Compare = Compare(), Container = Container()) -> priority_queue</*iter-value-type*/<InputIt>, Container, Compare>; template<class Compare, class Container, class Allocator> priority_queue(Compare, Container, Allocator) -> priority_queue<typename Container::value_type, Container, Compare>; template<class InputIt, class Allocator> priority_queue(InputIt, InputIt, Allocator) -> priority_queue</*iter-value-type*/<InputIt>, vector</*iter-value-type*/<InputIt>, Allocator>, less</*iter-value-type*/<InputIt>>>; template<class InputIt, class Compare, class Allocator> priority_queue(InputIt, InputIt, Compare, Allocator) -> priority_queue</*iter-value-type*/<InputIt>, vector</*iter-value-type*/<InputIt>, Allocator>, Compare>; template<class InputIt, class Compare, class Container, class Allocator> priority_queue(InputIt, InputIt, Compare, Container, Allocator) -> priority_queue<typename Container::value_type, Container, Compare>; // 不提供相等 template<class T, class Container, class Compare, class Alloc> struct uses_allocator<priority_queue<T, Container, Compare>, Alloc> : uses_allocator<Container, Alloc>::type { }; }