标准库头文件 <map>
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 | |
键值对的集合,按照键排序,键是唯一的 (类模板) | |
键值对的集合,按照键排序 (类模板) | |
函数 | |
(C++20 中移除)(C++20 中移除)(C++20 中移除)(C++20 中移除)(C++20 中移除)(C++20) |
按照字典顺序比较 map 中的值 (函数模板) |
特化 std::swap 算法 (函数模板) | |
(C++20) |
擦除所有满足特定判别标准的元素 (函数模板) |
(C++20 中移除)(C++20 中移除)(C++20 中移除)(C++20 中移除)(C++20 中移除)(C++20) |
按照字典顺序比较 multimap 中的值 (函数模板) |
特化 std::swap 算法 (函数模板) | |
(C++20) |
擦除所有满足特定判别标准的元素 (函数模板) |
范围访问 | |
(C++11)(C++14) |
返回指向容器或数组起始的迭代器 (函数模板) |
(C++11)(C++14) |
返回指向容器或数组结尾的迭代器 (函数模板) |
(C++14) |
返回指向一个容器或数组的逆向迭代器 (函数模板) |
(C++14) |
返回容器或数组的逆向尾迭代器 (函数模板) |
(C++17)(C++20) |
返回容器或数组的大小 (函数模板) |
(C++17) |
检查容器是否为空 (函数模板) |
(C++17) |
获得指向底层数组的指针 (函数模板) |
概要
#include <compare> #include <initializer_list> namespace std { // 类模板 map template<class Key, class T, class Compare = less<Key>, class Allocator = allocator<pair<const Key, T>>> class map; template<class Key, class T, class Compare, class Allocator> bool operator==(const map<Key, T, Compare, Allocator>& x, const map<Key, T, Compare, Allocator>& y); template<class Key, class T, class Compare, class Allocator> /*synth-three-way-result*/<pair<const Key, T>> operator<=>(const map<Key, T, Compare, Allocator>& x, const map<Key, T, Compare, Allocator>& y); template<class Key, class T, class Compare, class Allocator> void swap(map<Key, T, Compare, Allocator>& x, map<Key, T, Compare, Allocator>& y) noexcept(noexcept(x.swap(y))); template<class Key, class T, class Compare, class Allocator, class Predicate> typename map<Key, T, Compare, Allocator>::size_type erase_if(map<Key, T, Compare, Allocator>& c, Predicate pred); // 类模板 multimap template<class Key, class T, class Compare = less<Key>, class Allocator = allocator<pair<const Key, T>>> class multimap; template<class Key, class T, class Compare, class Allocator> bool operator==(const multimap<Key, T, Compare, Allocator>& x, const multimap<Key, T, Compare, Allocator>& y); template<class Key, class T, class Compare, class Allocator> /*synth-three-way-result*/<pair<const Key, T>> operator<=>(const multimap<Key, T, Compare, Allocator>& x, const multimap<Key, T, Compare, Allocator>& y); template<class Key, class T, class Compare, class Allocator> void swap(multimap<Key, T, Compare, Allocator>& x, multimap<Key, T, Compare, Allocator>& y) noexcept(noexcept(x.swap(y))); template<class Key, class T, class Compare, class Allocator, class Predicate> typename multimap<Key, T, Compare, Allocator>::size_type erase_if(multimap<Key, T, Compare, Allocator>& c, Predicate pred); namespace pmr { template<class Key, class T, class Compare = less<Key>> using map = std::map<Key, T, Compare, polymorphic_allocator<pair<const Key, T>>>; template<class Key, class T, class Compare = less<Key>> using multimap = std::multimap<Key, T, Compare, polymorphic_allocator<pair<const Key, T>>>; } }
类模板 std::map
namespace std { template<class Key, class T, class Compare = less<Key>, class Allocator = allocator<pair<const Key, T>>> class map { public: // 类型 using key_type = Key; using mapped_type = T; using value_type = pair<const Key, T>; using key_compare = Compare; using allocator_type = Allocator; using pointer = typename allocator_traits<Allocator>::pointer; using const_pointer = typename allocator_traits<Allocator>::const_pointer; using reference = value_type&; using const_reference = const value_type&; using size_type = /* 由实现定义 */; using difference_type = /* 由实现定义 */; using iterator = /* 由实现定义 */; using const_iterator = /* 由实现定义 */; using reverse_iterator = std::reverse_iterator<iterator>; using const_reverse_iterator = std::reverse_iterator<const_iterator>; using node_type = /* 未指明 */; using insert_return_type = /*insert-return-type*/<iterator, node_type>; class value_compare { friend class map; protected: Compare comp; value_compare(Compare c) : comp(c) {} public: bool operator()(const value_type& x, const value_type& y) const { return comp(x.first, y.first); } }; // 构造/复制/销毁 map() : map(Compare()) { } explicit map(const Compare& comp, const Allocator& = Allocator()); template<class InputIt> map(InputIt first, InputIt last, const Compare& comp = Compare(), const Allocator& = Allocator()); map(const map& x); map(map&& x); explicit map(const Allocator&); map(const map&, const Allocator&); map(map&&, const Allocator&); map(initializer_list<value_type>, const Compare& = Compare(), const Allocator& = Allocator()); template<class InputIt> map(InputIt first, InputIt last, const Allocator& a) : map(first, last, Compare(), a) { } map(initializer_list<value_type> il, const Allocator& a) : map(il, Compare(), a) { } ~map(); map& operator=(const map& x); map& operator=(map&& x) noexcept(allocator_traits<Allocator>::is_always_equal::value && is_nothrow_move_assignable_v<Compare>); map& operator=(initializer_list<value_type>); allocator_type get_allocator() const noexcept; // 迭代器 iterator begin() noexcept; const_iterator begin() const noexcept; iterator end() noexcept; const_iterator end() const noexcept; reverse_iterator rbegin() noexcept; const_reverse_iterator rbegin() const noexcept; reverse_iterator rend() noexcept; const_reverse_iterator rend() const noexcept; const_iterator cbegin() const noexcept; const_iterator cend() const noexcept; const_reverse_iterator crbegin() const noexcept; const_reverse_iterator crend() const noexcept; // 容量 [[nodiscard]] bool empty() const noexcept; size_type size() const noexcept; size_type max_size() const noexcept; // 元素访问 mapped_type& operator[](const key_type& x); mapped_type& operator[](key_type&& x); mapped_type& at(const key_type& x); const mapped_type& at(const key_type& x) const; // 修改器 template<class... Args> pair<iterator, bool> emplace(Args&&... args); template<class... Args> iterator emplace_hint(const_iterator position, Args&&... args); pair<iterator, bool> insert(const value_type& x); pair<iterator, bool> insert(value_type&& x); template<class P> pair<iterator, bool> insert(P&& x); iterator insert(const_iterator position, const value_type& x); iterator insert(const_iterator position, value_type&& x); template<class P> iterator insert(const_iterator position, P&&); template<class InputIt> void insert(InputIt first, InputIt last); void insert(initializer_list<value_type>); node_type extract(const_iterator position); node_type extract(const key_type& x); insert_return_type insert(node_type&& nh); iterator insert(const_iterator hint, node_type&& nh); template<class... Args> pair<iterator, bool> try_emplace(const key_type& k, Args&&... args); template<class... Args> pair<iterator, bool> try_emplace(key_type&& k, Args&&... args); template<class... Args> iterator try_emplace(const_iterator hint, const key_type& k, Args&&... args); template<class... Args> iterator try_emplace(const_iterator hint, key_type&& k, Args&&... args); template<class M> pair<iterator, bool> insert_or_assign(const key_type& k, M&& obj); template<class M> pair<iterator, bool> insert_or_assign(key_type&& k, M&& obj); template<class M> iterator insert_or_assign(const_iterator hint, const key_type& k, M&& obj); template<class M> iterator insert_or_assign(const_iterator hint, key_type&& k, M&& obj); iterator erase(iterator position); iterator erase(const_iterator position); size_type erase(const key_type& x); iterator erase(const_iterator first, const_iterator last); void swap(map&) noexcept(allocator_traits<Allocator>::is_always_equal::value && is_nothrow_swappable_v<Compare>); void clear() noexcept; template<class C2> void merge(map<Key, T, C2, Allocator>& source); template<class C2> void merge(map<Key, T, C2, Allocator>&& source); template<class C2> void merge(multimap<Key, T, C2, Allocator>& source); template<class C2> void merge(multimap<Key, T, C2, Allocator>&& source); // 观察器 key_compare key_comp() const; value_compare value_comp() const; // map 操作 iterator find(const key_type& x); const_iterator find(const key_type& x) const; template<class K> iterator find(const K& x); template<class K> const_iterator find(const K& x) const; size_type count(const key_type& x) const; template<class K> size_type count(const K& x) const; bool contains(const key_type& x) const; template<class K> bool contains(const K& x) const; iterator lower_bound(const key_type& x); const_iterator lower_bound(const key_type& x) const; template<class K> iterator lower_bound(const K& x); template<class K> const_iterator lower_bound(const K& x) const; iterator upper_bound(const key_type& x); const_iterator upper_bound(const key_type& x) const; template<class K> iterator upper_bound(const K& x); template<class K> const_iterator upper_bound(const K& x) const; pair<iterator, iterator> equal_range(const key_type& x); pair<const_iterator, const_iterator> equal_range(const key_type& x) const; template<class K> pair<iterator, iterator> equal_range(const K& x); template<class K> pair<const_iterator, const_iterator> equal_range(const K& x) const; }; template<class InputIt, class Compare = less</*iter-key-type*/<InputIt>>, class Allocator = allocator</*iter-to-alloc-type*/<InputIt>>> map(InputIt, InputIt, Compare = Compare(), Allocator = Allocator()) -> map</*iter-key-type*/<InputIt>, /*iter-mapped-type*/<InputIt>, Compare, Allocator>; template<class Key, class T, class Compare = less<Key>, class Allocator = allocator<pair<const Key, T>>> map(initializer_list<pair<Key, T>>, Compare = Compare(), Allocator = Allocator()) -> map<Key, T, Compare, Allocator>; template<class InputIt, class Allocator> map(InputIt, InputIt, Allocator) -> map</*iter-key-type*/<InputIt>, /*iter-mapped-type*/<InputIt>, less</*iter-key-type*/<InputIt>>, Allocator>; template<class Key, class T, class Allocator> map(initializer_list<pair<Key, T>>, Allocator) -> map<Key, T, less<Key>, Allocator>; // 交换 template<class Key, class T, class Compare, class Allocator> void swap(map<Key, T, Compare, Allocator>& x, map<Key, T, Compare, Allocator>& y) noexcept(noexcept(x.swap(y))); }
类模板 std::multimap
namespace std { template<class Key, class T, class Compare = less<Key>, class Allocator = allocator<pair<const Key, T>>> class multimap { public: // 类型 using key_type = Key; using mapped_type = T; using value_type = pair<const Key, T>; using key_compare = Compare; using allocator_type = Allocator; using pointer = typename allocator_traits<Allocator>::pointer; using const_pointer = typename allocator_traits<Allocator>::const_pointer; using reference = value_type&; using const_reference = const value_type&; using size_type = /* 由实现定义 */; using difference_type = /* 由实现定义 */; using iterator = /* 由实现定义 */; using const_iterator = /* 由实现定义 */; using reverse_iterator = std::reverse_iterator<iterator>; using const_reverse_iterator = std::reverse_iterator<const_iterator>; using node_type = /* 未指明 */; class value_compare { friend class multimap; protected: Compare comp; value_compare(Compare c) : comp(c) { } public: bool operator()(const value_type& x, const value_type& y) const { return comp(x.first, y.first); } }; // 构造/复制/销毁 multimap() : multimap(Compare()) { } explicit multimap(const Compare& comp, const Allocator& = Allocator()); template<class InputIt> multimap(InputIt first, InputIt last, const Compare& comp = Compare(), const Allocator& = Allocator()); multimap(const multimap& x); multimap(multimap&& x); explicit multimap(const Allocator&); multimap(const multimap&, const Allocator&); multimap(multimap&&, const Allocator&); multimap(initializer_list<value_type>, const Compare& = Compare(), const Allocator& = Allocator()); template<class InputIt> multimap(InputIt first, InputIt last, const Allocator& a) : multimap(first, last, Compare(), a) { } multimap(initializer_list<value_type> il, const Allocator& a) : multimap(il, Compare(), a) { } ~multimap(); multimap& operator=(const multimap& x); multimap& operator=(multimap&& x) noexcept(allocator_traits<Allocator>::is_always_equal::value && is_nothrow_move_assignable_v<Compare>); multimap& operator=(initializer_list<value_type>); allocator_type get_allocator() const noexcept; // 迭代器 iterator begin() noexcept; const_iterator begin() const noexcept; iterator end() noexcept; const_iterator end() const noexcept; reverse_iterator rbegin() noexcept; const_reverse_iterator rbegin() const noexcept; reverse_iterator rend() noexcept; const_reverse_iterator rend() const noexcept; const_iterator cbegin() const noexcept; const_iterator cend() const noexcept; const_reverse_iterator crbegin() const noexcept; const_reverse_iterator crend() const noexcept; // 容量 [[nodiscard]] bool empty() const noexcept; size_type size() const noexcept; size_type max_size() const noexcept; // 修改器 template<class... Args> iterator emplace(Args&&... args); template<class... Args> iterator emplace_hint(const_iterator position, Args&&... args); iterator insert(const value_type& x); iterator insert(value_type&& x); template<class P> iterator insert(P&& x); iterator insert(const_iterator position, const value_type& x); iterator insert(const_iterator position, value_type&& x); template<class P> iterator insert(const_iterator position, P&& x); template<class InputIt> void insert(InputIt first, InputIt last); void insert(initializer_list<value_type>); node_type extract(const_iterator position); node_type extract(const key_type& x); iterator insert(node_type&& nh); iterator insert(const_iterator hint, node_type&& nh); iterator erase(iterator position); iterator erase(const_iterator position); size_type erase(const key_type& x); iterator erase(const_iterator first, const_iterator last); void swap(multimap&) noexcept(allocator_traits<Allocator>::is_always_equal::value && is_nothrow_swappable_v<Compare>); void clear() noexcept; template<class C2> void merge(multimap<Key, T, C2, Allocator>& source); template<class C2> void merge(multimap<Key, T, C2, Allocator>&& source); template<class C2> void merge(map<Key, T, C2, Allocator>& source); template<class C2> void merge(map<Key, T, C2, Allocator>&& source); // 观察器 key_compare key_comp() const; value_compare value_comp() const; // map 操作 iterator find(const key_type& x); const_iterator find(const key_type& x) const; template<class K> iterator find(const K& x); template<class K> const_iterator find(const K& x) const; size_type count(const key_type& x) const; template<class K> size_type count(const K& x) const; bool contains(const key_type& x) const; template<class K> bool contains(const K& x) const; iterator lower_bound(const key_type& x); const_iterator lower_bound(const key_type& x) const; template<class K> iterator lower_bound(const K& x); template<class K> const_iterator lower_bound(const K& x) const; iterator upper_bound(const key_type& x); const_iterator upper_bound(const key_type& x) const; template<class K> iterator upper_bound(const K& x); template<class K> const_iterator upper_bound(const K& x) const; pair<iterator, iterator> equal_range(const key_type& x); pair<const_iterator, const_iterator> equal_range(const key_type& x) const; template<class K> pair<iterator, iterator> equal_range(const K& x); template<class K> pair<const_iterator, const_iterator> equal_range(const K& x) const; }; template<class InputIt, class Compare = less</*iter-key-type*/<InputIt>>, class Allocator = allocator</*iter-to-alloc-type*/<InputIt>>> multimap(InputIt, InputIt, Compare = Compare(), Allocator = Allocator()) -> multimap</*iter-key-type*/<InputIt>, /*iter-mapped-type*/<InputIt>, Compare, Allocator>; template<class Key, class T, class Compare = less<Key>, class Allocator = allocator<pair<const Key, T>>> multimap(initializer_list<pair<Key, T>>, Compare = Compare(), Allocator = Allocator()) -> multimap<Key, T, Compare, Allocator>; template<class InputIt, class Allocator> multimap(InputIt, InputIt, Allocator) -> multimap</*iter-key-type*/<InputIt>, /*iter-mapped-type*/<InputIt>, less</*iter-key-type*/<InputIt>>, Allocator>; template<class Key, class T, class Allocator> multimap(initializer_list<pair<Key, T>>, Allocator) -> multimap<Key, T, less<Key>, Allocator>; // 交换 template<class Key, class T, class Compare, class Allocator> void swap(multimap<Key, T, Compare, Allocator>& x, multimap<Key, T, Compare, Allocator>& y) noexcept(noexcept(x.swap(y))); }