标准库头文件 <vector>

来自cppreference.com
< cpp‎ | header
 
 
 

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
std::initializer_list 类模板

动态的连续数组
(类模板)
节省空间的动态 bitset
(类模板特化)
std::vector<bool> 的散列支持
(类模板特化)
前置声明
定义于头文件 <functional>
(C++11)
散列函数对象
(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 vector 中的值
(函数模板)
特化 std::swap 算法
(函数模板)
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)
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 vector
  template<class T, class Allocator = allocator<T>> class vector;
 
  template<class T, class Allocator>
    constexpr bool operator==(const vector<T, Allocator>& x,
                              const vector<T, Allocator>& y);
  template<class T, class Allocator>
    constexpr /*synth-three-way-result*/<T> operator<=>(const vector<T, Allocator>& x,
                                                        const vector<T, Allocator>& y);
 
  template<class T, class Allocator>
    constexpr void swap(vector<T, Allocator>& x, vector<T, Allocator>& y)
      noexcept(noexcept(x.swap(y)));
 
  template<class T, class Allocator, class U>
    constexpr typename vector<T, Allocator>::size_type
      erase(vector<T, Allocator>& c, const U& value);
  template<class T, class Allocator, class Predicate>
    constexpr typename vector<T, Allocator>::size_type
      erase_if(vector<T, Allocator>& c, Predicate pred);
 
  // 类 vector<bool>
  template<class Allocator> class vector<bool, Allocator>;
 
  // 散列支持
  template<class T> struct hash;
  template<class Allocator> struct hash<vector<bool, Allocator>>;
 
  namespace pmr {
    template<class T>
      using vector = std::vector<T, polymorphic_allocator<T>>;
  }
}

类模板 std::vector

namespace std {
  template<class T, class Allocator = allocator<T>>
  class vector {
  public:
    // 类型
    using value_type             = T;
    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>;
 
    // 构造/复制/销毁
    constexpr vector() noexcept(noexcept(Allocator())) : vector(Allocator()) { }
    constexpr explicit vector(const Allocator&) noexcept;
    constexpr explicit vector(size_type n, const Allocator& = Allocator());
    constexpr vector(size_type n, const T& value, const Allocator& = Allocator());
    template<class InputIt>
      constexpr vector(InputIt first, InputIt last, const Allocator& = Allocator());
    constexpr vector(const vector& x);
    constexpr vector(vector&&) noexcept;
    constexpr vector(const vector&, const Allocator&);
    constexpr vector(vector&&, const Allocator&);
    constexpr vector(initializer_list<T>, const Allocator& = Allocator());
    constexpr ~vector();
    constexpr vector& operator=(const vector& x);
    constexpr vector& operator=(vector&& x)
      noexcept(allocator_traits<Allocator>::propagate_on_container_move_assignment::value ||
               allocator_traits<Allocator>::is_always_equal::value);
    constexpr vector& operator=(initializer_list<T>);
    template<class InputIt>
      constexpr void assign(InputIt first, InputIt last);
    constexpr void assign(size_type n, const T& u);
    constexpr void assign(initializer_list<T>);
    constexpr allocator_type get_allocator() const noexcept;
 
    // 迭代器
    constexpr iterator               begin() noexcept;
    constexpr const_iterator         begin() const noexcept;
    constexpr iterator               end() noexcept;
    constexpr const_iterator         end() const noexcept;
    constexpr reverse_iterator       rbegin() noexcept;
    constexpr const_reverse_iterator rbegin() const noexcept;
    constexpr reverse_iterator       rend() noexcept;
    constexpr const_reverse_iterator rend() const noexcept;
 
    constexpr const_iterator         cbegin() const noexcept;
    constexpr const_iterator         cend() const noexcept;
    constexpr const_reverse_iterator crbegin() const noexcept;
    constexpr const_reverse_iterator crend() const noexcept;
 
    // 容量
    [[nodiscard]] constexpr bool empty() const noexcept;
    constexpr size_type size() const noexcept;
    constexpr size_type max_size() const noexcept;
    constexpr size_type capacity() const noexcept;
    constexpr void      resize(size_type sz);
    constexpr void      resize(size_type sz, const T& c);
    constexpr void      reserve(size_type n);
    constexpr void      shrink_to_fit();
 
    // 元素访问
    constexpr reference       operator[](size_type n);
    constexpr const_reference operator[](size_type n) const;
    constexpr const_reference at(size_type n) const;
    constexpr reference       at(size_type n);
    constexpr reference       front();
    constexpr const_reference front() const;
    constexpr reference       back();
    constexpr const_reference back() const;
 
    // 数据访问
    constexpr T*       data() noexcept;
    constexpr const T* data() const noexcept;
 
    // 修改器
    template<class... Args> constexpr reference emplace_back(Args&&... args);
    constexpr void push_back(const T& x);
    constexpr void push_back(T&& x);
    constexpr void pop_back();
 
    template<class... Args>
      constexpr iterator emplace(const_iterator position, Args&&... args);
    constexpr iterator insert(const_iterator position, const T& x);
    constexpr iterator insert(const_iterator position, T&& x);
    constexpr iterator insert(const_iterator position, size_type n, const T& x);
    template<class InputIt>
      constexpr iterator insert(const_iterator position,
                                InputIt first, InputIt last);
    constexpr iterator insert(const_iterator position, initializer_list<T> il);
    constexpr iterator erase(const_iterator position);
    constexpr iterator erase(const_iterator first, const_iterator last);
    constexpr void     swap(vector&)
      noexcept(allocator_traits<Allocator>::propagate_on_container_swap::value ||
               allocator_traits<Allocator>::is_always_equal::value);
    constexpr void     clear() noexcept;
  };
 
  template<class InputIt, class Allocator = allocator</*iter-value-type*/<InputIt>>>
    vector(InputIt, InputIt, Allocator = Allocator())
      -> vector</*iter-value-type*/<InputIt>, Allocator>;
 
  // 交换
  template<class T, class Allocator>
    constexpr void swap(vector<T, Allocator>& x, vector<T, Allocator>& y)
      noexcept(noexcept(x.swap(y)));
}

类模板 std::vectorbool 的特化

namespace std {
  template<class Allocator>
  class vector<bool, Allocator> {
  public:
    // 类型
    using value_type             = bool;
    using allocator_type         = Allocator;
    using pointer                = /* 由实现定义 */;
    using const_pointer          = /* 由实现定义 */;
    using const_reference        = bool;
    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>;
 
    // 位引用
    class reference {
      friend class vector;
      constexpr reference() noexcept;
    public:
      constexpr reference(const reference&) = default;
      constexpr ~reference();
      constexpr operator bool() const noexcept;
      constexpr reference& operator=(const bool x) noexcept;
      constexpr reference& operator=(const reference& x) noexcept;
      constexpr void flip() noexcept;   // 翻转位
    };
 
    // 构造/复制/销毁
    constexpr vector() : vector(Allocator()) { }
    constexpr explicit vector(const Allocator&);
    constexpr explicit vector(size_type n, const Allocator& = Allocator());
    constexpr vector(size_type n, const bool& value, const Allocator& = Allocator());
    template<class InputIt>
      constexpr vector(InputIt first, InputIt last, const Allocator& = Allocator());
    constexpr vector(const vector& x);
    constexpr vector(vector&& x);
    constexpr vector(const vector&, const Allocator&);
    constexpr vector(vector&&, const Allocator&);
    constexpr vector(initializer_list<bool>, const Allocator& = Allocator()));
    constexpr ~vector();
    constexpr vector& operator=(const vector& x);
    constexpr vector& operator=(vector&& x);
    constexpr vector& operator=(initializer_list<bool>);
    template<class InputIt>
      constexpr void assign(InputIt first, InputIt last);
    constexpr void assign(size_type n, const bool& t);
    constexpr void assign(initializer_list<bool>);
    constexpr allocator_type get_allocator() const noexcept;
 
    // 迭代器
    constexpr iterator               begin() noexcept;
    constexpr const_iterator         begin() const noexcept;
    constexpr iterator               end() noexcept;
    constexpr const_iterator         end() const noexcept;
    constexpr reverse_iterator       rbegin() noexcept;
    constexpr const_reverse_iterator rbegin() const noexcept;
    constexpr reverse_iterator       rend() noexcept;
    constexpr const_reverse_iterator rend() const noexcept;
 
    constexpr const_iterator         cbegin() const noexcept;
    constexpr const_iterator         cend() const noexcept;
    constexpr const_reverse_iterator crbegin() const noexcept;
    constexpr const_reverse_iterator crend() const noexcept;
 
    // 容量
    [[nodiscard]] constexpr bool empty() const noexcept;
    constexpr size_type size() const noexcept;
    constexpr size_type max_size() const noexcept;
    constexpr size_type capacity() const noexcept;
    constexpr void      resize(size_type sz, bool c = false);
    constexpr void      reserve(size_type n);
    constexpr void      shrink_to_fit();
 
    // 元素访问
    constexpr reference       operator[](size_type n);
    constexpr const_reference operator[](size_type n) const;
    constexpr const_reference at(size_type n) const;
    constexpr reference       at(size_type n);
    constexpr reference       front();
    constexpr const_reference front() const;
    constexpr reference       back();
    constexpr const_reference back() const;
 
    // 修改器
    template<class... Args> constexpr reference emplace_back(Args&&... args);
    constexpr void push_back(const bool& x);
    constexpr void pop_back();
    template<class... Args>
      constexpr iterator emplace(const_iterator position, Args&&... args);
    constexpr iterator insert(const_iterator position, const bool& x);
    constexpr iterator insert(const_iterator position, size_type n, const bool& x);
    template<class InputIt>
      constexpr iterator insert(const_iterator position,
                                InputIt first, InputIt last);
    constexpr iterator insert(const_iterator position, initializer_list<bool> il);
 
    constexpr iterator erase(const_iterator position);
    constexpr iterator erase(const_iterator first, const_iterator last);
    constexpr void swap(vector&);
    constexpr static void swap(reference x, reference y) noexcept;
    constexpr void flip() noexcept;     // 翻转所有位
    constexpr void clear() noexcept;
  };
}