标准库头文件 <algorithm>

此头文件是算法库的一部分。

[编辑] 函数

不修改序列的操作
all_ofany_ofnone_of (C++11)(C++11)(C++11)	检查谓词是否对范围中所有、任一或无元素为 true (函数模板) [编辑]
for_each	应用函数到范围中的元素 (函数模板) [编辑]
for_each_n (C++17)	应用一个函数对象到序列的前 n 个元素 (函数模板) [编辑]
countcount_if	返回满足指定判别标准的元素数 (函数模板) [编辑]
mismatch	寻找两个范围出现不同的首个位置 (函数模板) [编辑]
findfind_iffind_if_not (C++11)	寻找首个满足特定判别标准的元素 (函数模板) [编辑]
find_end	在特定范围中寻找最后出现的元素序列 (函数模板) [编辑]
find_first_of	搜索元素集合中的任意元素 (函数模板) [编辑]
adjacent_find	查找首对相邻的相同（或满足给定谓词的）元素 (函数模板) [编辑]
search	搜索一个元素范围 (函数模板) [编辑]
search_n	在范围中搜索一定量的某个元素的连续副本 (函数模板) [编辑]
修改序列的操作
copycopy_if (C++11)	将某一范围的元素复制到一个新的位置 (函数模板) [编辑]
copy_n (C++11)	将一定数目的元素复制到一个新的位置 (函数模板) [编辑]
copy_backward	按从后往前的顺序复制一个范围内的元素 (函数模板) [编辑]
move (C++11)	将某一范围的元素移动到一个新的位置 (函数模板) [编辑]
move_backward (C++11)	按从后往前的顺序移动某一范围的元素到新的位置 (函数模板) [编辑]
fill	将一个给定值复制赋值给一个范围内的每个元素 (函数模板) [编辑]
fill_n	将一个给定值复制赋值给一个范围内的 N 个元素 (函数模板) [编辑]
transform	将一个函数应用于某一范围的各个元素 (函数模板) [编辑]
generate	将相继的函数调用结果赋值给一个范围中的每个元素 (函数模板) [编辑]
generate_n	将相继的函数调用结果赋值给一个范围中的 N 个元素 (函数模板) [编辑]
removeremove_if	移除满足特定判别标准的元素 (函数模板) [编辑]
remove_copyremove_copy_if	复制一个范围的元素，忽略满足特定判别标准的元素 (函数模板) [编辑]
replacereplace_if	将所有满足特定判别标准的值替换为另一个值 (函数模板) [编辑]
replace_copyreplace_copy_if	复制一个范围内的元素，并将满足特定判别标准的元素替换为另一个值 (函数模板) [编辑]
swap	交换两个对象的值 (函数模板) [编辑]
swap_ranges	交换两个范围的元素 (函数模板) [编辑]
iter_swap	交换两个迭代器所指向的元素 (函数模板) [编辑]
reverse	逆转范围中的元素顺序 (函数模板) [编辑]
reverse_copy	创建一个范围的逆向副本 (函数模板) [编辑]
rotate	旋转范围中的元素顺序 (函数模板) [编辑]
rotate_copy	复制并旋转元素范围 (函数模板) [编辑]
shift_leftshift_right (C++20)	迁移范围中的元素 (函数模板) [编辑]
random_shuffleshuffle (C++17 前)(C++11)	随机重排范围中的元素 (函数模板) [编辑]
sample (C++17)	从一个序列中随机选择 n 个元素 (函数模板) [编辑]
unique	移除范围内的连续重复元素 (函数模板) [编辑]
unique_copy	创建某范围的不含连续重复元素的副本 (函数模板) [编辑]
划分操作
is_partitioned (C++11)	判断范围是否已按给定的谓词划分 (函数模板) [编辑]
partition	将范围中的元素分为两组 (函数模板) [编辑]
partition_copy (C++11)	复制一个范围，将各元素分为两组 (函数模板) [编辑]
stable_partition	将元素分为两组，同时保留其相对顺序 (函数模板) [编辑]
partition_point (C++11)	定位已划分范围的划分点 (函数模板) [编辑]
排序操作
is_sorted (C++11)	检查范围是否已按升序排列 (函数模板) [编辑]
is_sorted_until (C++11)	找出最大的已排序子范围 (函数模板) [编辑]
sort	将范围按升序排序 (函数模板) [编辑]
partial_sort	排序一个范围的前 N 个元素 (函数模板) [编辑]
partial_sort_copy	对范围内的元素进行复制并部分排序 (函数模板) [编辑]
stable_sort	将范围内的元素排序，同时保持相等的元素之间的顺序 (函数模板) [编辑]
nth_element	将给定的范围部分排序，确保其按给定元素划分 (函数模板) [编辑]
（已排序范围上的）二分搜索操作
lower_bound	返回指向第一个不小于给定值的元素的迭代器 (函数模板) [编辑]
upper_bound	返回指向第一个大于给定值的元素的迭代器 (函数模板) [编辑]
binary_search	确定元素是否存在于某范围中 (函数模板) [编辑]
equal_range	返回匹配特定键值的元素范围 (函数模板) [编辑]
其他已排序范围上的操作
merge	归并两个已排序的范围 (函数模板) [编辑]
inplace_merge	就地归并两个有序范围 (函数模板) [编辑]
（已排序范围上的）集合操作
includes	若一个集合是另一个的子集则返回 true (函数模板) [编辑]
set_difference	计算两个集合的差集 (函数模板) [编辑]
set_intersection	计算两个集合的交集 (函数模板) [编辑]
set_symmetric_difference	计算两个集合的对称差 (函数模板) [编辑]
set_union	计算两个集合的并集 (函数模板) [编辑]
堆操作
is_heap	检查给定范围是否为一个最大堆 (函数模板) [编辑]
is_heap_until (C++11)	查找能成为最大堆的最大子范围 (函数模板) [编辑]
make_heap	从一个元素范围创建出一个最大堆 (函数模板) [编辑]
push_heap	将一个元素加入到一个最大堆 (函数模板) [编辑]
pop_heap	从最大堆中移除最大元素 (函数模板) [编辑]
sort_heap	将一个最大堆变成一个按升序排序的元素范围 (函数模板) [编辑]
最小/最大操作
max	返回各给定值中的较大者 (函数模板) [编辑]
max_element	返回范围内的最大元素 (函数模板) [编辑]
min	返回各给定值中的较小者 (函数模板) [编辑]
min_element	返回范围内的最小元素 (函数模板) [编辑]
minmax (C++11)	返回两个元素的较小和较大者 (函数模板) [编辑]
minmax_element (C++11)	返回范围内的最小元素和最大元素 (函数模板) [编辑]
clamp (C++17)	在一对边界值间夹逼一个值 (函数模板) [编辑]
比较操作
equal	确定两个元素集合是否是相同的 (函数模板) [编辑]
lexicographical_compare	当一个范围按字典顺序小于另一个范围时，返回 true (函数模板) [编辑]
compare_3way (C++20)	用三路比较比较两个值 (函数模板) [编辑]
lexicographical_compare_3way (C++20)	用三路比较比较两个范围 (函数模板) [编辑]
排列操作
is_permutation (C++11)	判断一个序列是否为另一个序列的排列 (函数模板) [编辑]
next_permutation	产生某个元素范围的按字典顺序的下一个较大的排列 (函数模板) [编辑]
prev_permutation	产生某个元素范围的按字典顺序的下一个较小的排列 (函数模板) [编辑]

[编辑] Niebloid

定义于命名空间 `std::ranges`
不修改序列的操作
all_ofany_ofnone_of	检查谓词是否对范围中所有、任一或无元素为 true (niebloid) [编辑]
for_each	应用函数到范围中的元素 (niebloid) [编辑]
countcount_if	返回满足指定判别标准的元素数 (niebloid) [编辑]
mismatch	寻找两个范围出现不同的首个位置 (niebloid) [编辑]
findfind_iffind_if_not	寻找首个满足特定判别标准的元素 (niebloid) [编辑]
find_end	在特定范围中寻找最后出现的元素序列 (niebloid) [编辑]
find_first_of	搜索元素集合中的任意元素 (niebloid) [编辑]
adjacent_find	查找首对相邻的相同（或满足给定谓词的）元素 (niebloid) [编辑]
search	搜索一个元素范围 (niebloid) [编辑]
search_n	在范围中搜索一定量的某个元素的连续副本 (niebloid) [编辑]
修改序列的操作
copycopy_if	将某一范围的元素复制到一个新的位置 (niebloid) [编辑]
copy_n	将一定数目的元素复制到一个新的位置 (niebloid) [编辑]
copy_backward	按从后往前的顺序复制一个范围内的元素 (niebloid) [编辑]
move	将某一范围的元素移动到一个新的位置 (niebloid) [编辑]
move_backward	按从后往前的顺序移动某一范围的元素到新的位置 (niebloid) [编辑]
fill	将一个给定值复制赋值给一个范围内的每个元素 (niebloid) [编辑]
fill_n	将一个值复制赋值给一定量的元素 (niebloid) [编辑]
transform	将一个函数应用于某一范围的各个元素 (niebloid) [编辑]
generate	保存函数结果到一个范围中 (niebloid) [编辑]
generate_n	保存 N 次函数应用的结果 (niebloid) [编辑]
removeremove_if	移除满足特定判别标准的元素 (niebloid) [编辑]
remove_copyremove_copy_if	复制一个范围的元素，忽略满足特定判别标准的元素 (niebloid) [编辑]
replacereplace_if	将所有满足特定判别标准的值替换为另一个值 (niebloid) [编辑]
replace_copyreplace_copy_if	复制一个范围内的元素，并将满足特定判别标准的元素替换为另一个值 (niebloid) [编辑]
swap_ranges	交换两个范围的元素 (niebloid) [编辑]
reverse	逆转范围中的元素顺序 (niebloid) [编辑]
reverse_copy	创建一个范围的逆向副本 (niebloid) [编辑]
rotate	旋转范围中的元素顺序 (niebloid) [编辑]
rotate_copy	复制并旋转元素范围 (niebloid) [编辑]
shuffle	随机重排范围中的元素 (niebloid) [编辑]
unique	移除范围中的连续重复元素 (niebloid) [编辑]
unique_copy	创建某范围的不含连续重复元素的副本 (niebloid) [编辑]
划分操作
is_partitioned	判断范围是否已按给定的谓词划分 (niebloid) [编辑]
partition	将范围中的元素分为二组 (niebloid) [编辑]
partition_copy	复制一个范围，将各元素分为二组 (niebloid) [编辑]
stable_partition	将元素分成二组，同时保持其相对顺序 (niebloid) [编辑]
partition_point	定位已划分范围的划分点 (niebloid) [编辑]
排序操作
is_sorted	检查范围是否以升序排序 (niebloid) [编辑]
is_sorted_until	寻找最大的已排序子范围 (niebloid) [编辑]
sort	将范围按升序排序 (niebloid) [编辑]
partial_sort	排序一个范围的前 N 个元素 (niebloid) [编辑]
partial_sort_copy	对范围内的元素进行复制并部分排序 (niebloid) [编辑]
stable_sort	将范围内的元素排序，同时保持相等的元素之间的顺序 (niebloid) [编辑]
nth_element	将给定的范围部分排序，确保其按给定元素划分 (niebloid) [编辑]
（已排序范围上的）集合操作
lower_bound	返回指向首个不小于给定值的元素的迭代器 (niebloid) [编辑]
upper_bound	返回指向首个大于某值的元素的迭代器 (niebloid) [编辑]
binary_search	确定元素是否存在于某范围中 (niebloid) [编辑]
equal_range	返回匹配特定键值的元素范围 (niebloid) [编辑]
其他已排序范围上的操作
merge	归并二个已排序范围 (niebloid) [编辑]
inplace_merge	在原位归并两个有序范围 (niebloid) [编辑]
（已排序范围上的）集合操作
includes	若一个集合是另一个的子集则返回 `true` (niebloid) [编辑]
set_difference	计算两个集合的差集 (niebloid) [编辑]
set_intersection	计算两个集合的交集 (niebloid) [编辑]
set_symmetric_difference	计算两个集合的对称差 (niebloid) [编辑]
set_union	计算两个集合的并集 (niebloid) [编辑]
堆操作
is_heap	检查给定范围是否为最大堆 (niebloid) [编辑]
is_heap_until	寻找能成为最大堆的最大子范围 (niebloid) [编辑]
make_heap	从一个元素范围创建出一个最大堆 (niebloid) [编辑]
push_heap	将一个元素加入到一个最大堆 (niebloid) [编辑]
pop_heap	从最大堆中移除最大元素 (niebloid) [编辑]
sort_heap	将一个最大堆变成一个按升序排序的元素范围 (niebloid) [编辑]
最小/最大操作
max	返回给定值的较大者 (niebloid) [编辑]
max_element	返回范围中的最大元素 (niebloid) [编辑]
min	返回给定值的较小者 (niebloid) [编辑]
min_element	返回范围中的最小元素 (niebloid) [编辑]
minmax	返回两个元素的较小和较大者 (niebloid) [编辑]
minmax_element	返回范围中的最小和最大元素 (niebloid) [编辑]
比较操作
equal	确定两个元素集合是否是相同的 (niebloid) [编辑]
lexicographical_compare	当一个范围按字典顺序小于另一个范围时，返回 true (niebloid) [编辑]
排列操作
is_permutation	确定一个序列是否为另一序列的重排 (niebloid) [编辑]
next_permutation	产生某个元素范围的按字典序下一个较大的排列 (niebloid) [编辑]
prev_permutation	产生某个元素范围的按字典序下一个较小的排列 (niebloid) [编辑]

[编辑] 概要

#include <initializer_list>
 
namespace std {
  // 不修改序列的操作：
  // 全部（all of）：
  template<class InputIt, class Pred>
    constexpr bool all_of(InputIt first, InputIt last, Pred pred);
  template<class ExecutionPolicy, class ForwardIt, class Pred>
    bool all_of(ExecutionPolicy&& exec,
                ForwardIt first, ForwardIt last, Pred pred);
 
  namespace ranges {
    template<InputIterator I, Sentinel<I> S, class Proj = identity,
             IndirectUnaryPredicate<projected<I, Proj>> Pred>
      constexpr bool all_of(I first, S last, Pred pred, Proj proj = {});
    template<InputRange R, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      constexpr bool all_of(R&& r, Pred pred, Proj proj = {});
  }
 
  // 任一（any of）：
  template<class InputIt, class Pred>
    constexpr bool any_of(InputIt first, InputIt last, Pred pred);
  template<class ExecutionPolicy, class ForwardIt, class Pred>
    bool any_of(ExecutionPolicy&& exec,
                ForwardIt first, ForwardIt last, Pred pred);
 
  namespace ranges {
    template<InputIterator I, Sentinel<I> S, class Proj = identity,
             IndirectUnaryPredicate<projected<I, Proj>> Pred>
      constexpr bool any_of(I first, S last, Pred pred, Proj proj = {});
    template<InputRange R, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      constexpr bool any_of(R&& r, Pred pred, Proj proj = {});
  }
 
  // 无一（none of）：
  template<class InputIt, class Pred>
    constexpr bool none_of(InputIt first, InputIt last, Pred pred);
  template<class ExecutionPolicy, class ForwardIt, class Pred>
    bool none_of(ExecutionPolicy&& exec,
                 ForwardIt first, ForwardIt last, Pred pred);
 
  namespace ranges {
    template<InputIterator I, Sentinel<I> S, class Proj = identity,
             IndirectUnaryPredicate<projected<I, Proj>> Pred>
      constexpr bool none_of(I first, S last, Pred pred, Proj proj = {});
    template<InputRange R, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      constexpr bool none_of(R&& r, Pred pred, Proj proj = {});
  }
 
  // 对每元素（for each）：
  template<class InputIt, class Function>
    constexpr Function for_each(InputIt first, InputIt last, Function f);
  template<class ExecutionPolicy, class ForwardIt, class Function>
    void for_each(ExecutionPolicy&& exec,
                  ForwardIt first, ForwardIt last, Function f);
 
  namespace ranges {
    template<class I, class F>
    struct for_each_result {
      [[no_unique_address]] I in;
      [[no_unique_address]] F fun;
 
      template<class I2, class F2>
        requires ConvertibleTo<const I&, I2> && ConvertibleTo<const F&, F2>
        operator for_each_result<I2, F2>() const & {
          return {in, fun};
        }
 
      template<class I2, class F2>
        requires ConvertibleTo<I, I2> && ConvertibleTo<F, F2>
        operator for_each_result<I2, F2>() && {
          return {std::move(in), std::move(fun)};
        }
    };
 
    template<InputIterator I, Sentinel<I> S, class Proj = identity,
             IndirectUnaryInvocable<projected<I, Proj>> Fun>
      constexpr for_each_result<I, Fun>
        for_each(I first, S last, Fun f, Proj proj = {});
    template<InputRange R, class Proj = identity,
             IndirectUnaryInvocable<projected<iterator_t<R>, Proj>> Fun>
      constexpr for_each_result<safe_iterator_t<R>, Fun>
        for_each(R&& r, Fun f, Proj proj = {});
  }
 
  template<class InputIt, class Size, class Function>
    constexpr InputIt for_each_n(InputIt first, Size n, Function f);
  template<class ExecutionPolicy, class ForwardIt, class Size, class Function>
    ForwardIt for_each_n(ExecutionPolicy&& exec,
                         ForwardIt first, Size n, Function f);
 
  // 寻找（find）：
  template<class InputIt, class T>
    constexpr InputIt find(InputIt first, InputIt last,
                           const T& value);
  template<class ExecutionPolicy, class ForwardIt, class T>
    ForwardIt find(ExecutionPolicy&& exec,
                   ForwardIt first, ForwardIt last, const T& value);
  template<class InputIt, class Pred>
    constexpr InputIt find_if(InputIt first, InputIt last, Pred pred);
  template<class ExecutionPolicy, class ForwardIt, class Pred>
    ForwardIt find_if(ExecutionPolicy&& exec,
                      ForwardIt first, ForwardIt last, Pred pred);
  template<class InputIt, class Pred>
    constexpr InputIt find_if_not(InputIt first, InputIt last, Pred pred);
  template<class ExecutionPolicy, class ForwardIt, class Pred>
    ForwardIt find_if_not(ExecutionPolicy&& exec,
                          ForwardIt first, ForwardIt last, Pred pred);
 
  namespace ranges {
    template<InputIterator I, Sentinel<I> S, class T, class Proj = identity>
      requires IndirectRelation<ranges::equal_to, projected<I, Proj>, const T*>
      constexpr I find(I first, S last, const T& value, Proj proj = {});
    template<InputRange R, class T, class Proj = identity>
      requires IndirectRelation<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
      constexpr safe_iterator_t<R>
        find(R&& r, const T& value, Proj proj = {});
    template<InputIterator I, Sentinel<I> S, class Proj = identity,
             IndirectUnaryPredicate<projected<I, Proj>> Pred>
      constexpr I find_if(I first, S last, Pred pred, Proj proj = {});
    template<InputRange R, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      constexpr safe_iterator_t<R>
        find_if(R&& r, Pred pred, Proj proj = {});
    template<InputIterator I, Sentinel<I> S, class Proj = identity,
             IndirectUnaryPredicate<projected<I, Proj>> Pred>
      constexpr I find_if_not(I first, S last, Pred pred, Proj proj = {});
    template<InputRange R, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      constexpr safe_iterator_t<R>
        find_if_not(R&& r, Pred pred, Proj proj = {});
  }
 
  // 寻找末尾（find end）：
  template<class ForwardIt1, class ForwardIt2>
    constexpr ForwardIt1
      find_end(ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2);
  template<class ForwardIt1, class ForwardIt2, class BinaryPred>
    constexpr ForwardIt1
      find_end(ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2,
               BinaryPred pred);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    ForwardIt1
      find_end(ExecutionPolicy&& exec,
               ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2);
  template<class ExecutionPolicy, class ForwardIt1,
           class ForwardIt2, class BinaryPred>
    ForwardIt1
      find_end(ExecutionPolicy&& exec,
               ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2,
               BinaryPred pred);
 
  namespace ranges {
    template<ForwardIterator I1, Sentinel<I1> S1, ForwardIterator I2, Sentinel<I2> S2,
             class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyComparable<I1, I2, Pred, Proj1, Proj2>
      constexpr subrange<I1>
        find_end(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},
                 Proj1 proj1 = {}, Proj2 proj2 = {});
    template<ForwardRange R1, ForwardRange R2,
             class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyComparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
      constexpr safe_subrange_t<R1>
        find_end(R1&& r1, R2&& r2, Pred pred = {},
                 Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  // 寻找首个（find first）：
  template<class InputIt, class ForwardIt>
    constexpr InputIt
      find_first_of(InputIt first1, InputIt last1, ForwardIt first2, ForwardIt last2);
  template<class InputIt, class ForwardIt, class BinaryPred>
    constexpr InputIt
      find_first_of(InputIt first1, InputIt last1, ForwardIt first2, ForwardIt last2,
                    BinaryPred pred);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    ForwardIt1
      find_first_of(ExecutionPolicy&& exec,
                    ForwardIt1 first1, ForwardIt1 last1,
                    ForwardIt2 first2, ForwardIt2 last2);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class BinaryPred>
    ForwardIt1
      find_first_of(ExecutionPolicy&& exec,
                    ForwardIt1 first1, ForwardIt1 last1,
                    ForwardIt2 first2, ForwardIt2 last2,
                    BinaryPred pred);
 
  namespace ranges {
    template<InputIterator I1, Sentinel<I1> S1, ForwardIterator I2, Sentinel<I2> S2,
             class Proj1 = identity, class Proj2 = identity,
             IndirectRelation<projected<I1, Proj1>,
                              projected<I2, Proj2>> Pred = ranges::equal_to>
      constexpr I1 find_first_of(I1 first1, S1 last1, I2 first2, S2 last2,
                                 Pred pred = {},
                                 Proj1 proj1 = {}, Proj2 proj2 = {});
    template<InputRange R1, ForwardRange R2,
             class Proj1 = identity, class Proj2 = identity,
             IndirectRelation<projected<iterator_t<R1>, Proj1>,
                              projected<iterator_t<R2>, Proj2>> Pred = ranges::equal_to>
      constexpr safe_iterator_t<R1>
        find_first_of(R1&& r1, R2&& r2,
                      Pred pred = {},
                      Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  // 毗邻寻找（adjacent find）：
  template<class ForwardIt>
    constexpr ForwardIt
      adjacent_find(ForwardIt first, ForwardIt last);
  template<class ForwardIt, class BinaryPred>
    constexpr ForwardIt
      adjacent_find(ForwardIt first, ForwardIt last, BinaryPred pred);
  template<class ExecutionPolicy, class ForwardIt>
    ForwardIt
      adjacent_find(ExecutionPolicy&& exec,
                    ForwardIt first, ForwardIt last);
  template<class ExecutionPolicy, class ForwardIt, class BinaryPred>
    ForwardIt
      adjacent_find(ExecutionPolicy&& exec,
                    ForwardIt first, ForwardIt last, BinaryPred pred);
 
  namespace ranges {
    template<ForwardIterator I, Sentinel<I> S, class Proj = identity,
             IndirectRelation<projected<I, Proj>> Pred = ranges::equal_to>
      constexpr I adjacent_find(I first, S last, Pred pred = {},
                                Proj proj = {});
    template<ForwardRange R, class Proj = identity,
             IndirectRelation<projected<iterator_t<R>, Proj>> Pred = ranges::equal_to>
      constexpr safe_iterator_t<R>
        adjacent_find(R&& r, Pred pred = {}, Proj proj = {});
  }
 
  // 计数（count）：
  template<class InputIt, class T>
    constexpr typename iterator_traits<InputIt>::difference_type
      count(InputIt first, InputIt last, const T& value);
  template<class ExecutionPolicy, class ForwardIt, class T>
    typename iterator_traits<ForwardIt>::difference_type
      count(ExecutionPolicy&& exec,
            ForwardIt first, ForwardIt last, const T& value);
  template<class InputIt, class Pred>
    constexpr typename iterator_traits<InputIt>::difference_type
      count_if(InputIt first, InputIt last, Pred pred);
  template<class ExecutionPolicy, class ForwardIt, class Pred>
    typename iterator_traits<ForwardIt>::difference_type
      count_if(ExecutionPolicy&& exec,
               ForwardIt first, ForwardIt last, Pred pred);
 
  namespace ranges {
    template<InputIterator I, Sentinel<I> S, class T, class Proj = identity>
      requires IndirectRelation<ranges::equal_to, projected<I, Proj>, const T*>
      constexpr iter_difference_t<I>
        count(I first, S last, const T& value, Proj proj = {});
    template<InputRange R, class T, class Proj = identity>
      requires IndirectRelation<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
      constexpr iter_difference_t<iterator_t<R>>
        count(R&& r, const T& value, Proj proj = {});
    template<InputIterator I, Sentinel<I> S, class Proj = identity,
             IndirectUnaryPredicate<projected<I, Proj>> Pred>
      constexpr iter_difference_t<I>
        count_if(I first, S last, Pred pred, Proj proj = {});
    template<InputRange R, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      constexpr iter_difference_t<iterator_t<R>>
        count_if(R&& r, Pred pred, Proj proj = {});
  }
 
  // 不匹配（mismatch）：
  template<class InputIt1, class InputIt2>
    constexpr pair<InputIt1, InputIt2>
      mismatch(InputIt1 first1, InputIt1 last1, InputIt2 first2);
  template<class InputIt1, class InputIt2, class BinaryPred>
    constexpr pair<InputIt1, InputIt2>
      mismatch(InputIt1 first1, InputIt1 last1, InputIt2 first2, BinaryPred pred);
  template<class InputIt1, class InputIt2>
    constexpr pair<InputIt1, InputIt2>
      mismatch(InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2);
  template<class InputIt1, class InputIt2, class BinaryPred>
    constexpr pair<InputIt1, InputIt2>
      mismatch(InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2,
               BinaryPred pred);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    pair<ForwardIt1, ForwardIt2>
      mismatch(ExecutionPolicy&& exec,
               ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class BinaryPred>
    pair<ForwardIt1, ForwardIt2>
      mismatch(ExecutionPolicy&& exec,
               ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, BinaryPred pred);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    pair<ForwardIt1, ForwardIt2>
      mismatch(ExecutionPolicy&& exec,
               ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class BinaryPred>
    pair<ForwardIt1, ForwardIt2>
      mismatch(ExecutionPolicy&& exec,
               ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2,
               BinaryPred pred);
 
  namespace ranges {
    template<class I1, class I2>
    struct mismatch_result {
      [[no_unique_address]] I1 in1;
      [[no_unique_address]] I2 in2;
 
      template<class II1, class II2>
        requires ConvertibleTo<const I1&, II1> && ConvertibleTo<const I2&, II2>
        operator mismatch_result<II1, II2>() const & {
          return {in1, in2};
        }
 
      template<class II1, class II2>
        requires ConvertibleTo<I1, II1> && ConvertibleTo<I2, II2>
        operator mismatch_result<II1, II2>() && {
          return {std::move(in1), std::move(in2)};
        }
    };
 
    template<InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
             class Proj1 = identity, class Proj2 = identity,
             IndirectRelation<projected<I1, Proj1>,
                              projected<I2, Proj2>> Pred = ranges::equal_to>
      constexpr mismatch_result<I1, I2>
        mismatch(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},
                 Proj1 proj1 = {}, Proj2 proj2 = {});
    template<InputRange R1, InputRange R2,
             class Proj1 = identity, class Proj2 = identity,
             IndirectRelation<projected<iterator_t<R1>, Proj1>,
                              projected<iterator_t<R2>, Proj2>> Pred = ranges::equal_to>
      constexpr mismatch_result<safe_iterator_t<R1>, safe_iterator_t<R2>>
        mismatch(R1&& r1, R2&& r2, Pred pred = {},
                 Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  // 相等（equal）：
  template<class InputIt1, class InputIt2>
    constexpr bool equal(InputIt1 first1, InputIt1 last1, InputIt2 first2);
  template<class InputIt1, class InputIt2, class BinaryPred>
    constexpr bool equal(InputIt1 first1, InputIt1 last1, InputIt2 first2,
                         BinaryPred pred);
  template<class InputIt1, class InputIt2>
    constexpr bool equal(InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2);
  template<class InputIt1, class InputIt2, class BinaryPred>
    constexpr bool equal(InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2,
                         BinaryPred pred);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    bool equal(ExecutionPolicy&& exec,
               ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class BinaryPred>
    bool equal(ExecutionPolicy&& exec,
               ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, BinaryPred pred);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    bool equal(ExecutionPolicy&& exec,
               ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class BinaryPred>
    bool equal(ExecutionPolicy&& exec,
               ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2,
               BinaryPred pred);
 
  namespace ranges {
    template<InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
             class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyComparable<I1, I2, Pred, Proj1, Proj2>
      constexpr bool equal(I1 first1, S1 last1, I2 first2, S2 last2,
                           Pred pred = {},
                           Proj1 proj1 = {}, Proj2 proj2 = {});
    template<InputRange R1, InputRange R2, class Pred = ranges::equal_to,
             class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyComparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
      constexpr bool equal(R1&& r1, R2&& r2, Pred pred = {},
                           Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  // 是否为排列（is permutation）：
  template<class ForwardIt1, class ForwardIt2>
    constexpr bool is_permutation(ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2);
  template<class ForwardIt1, class ForwardIt2, class BinaryPred>
    constexpr bool is_permutation(ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2,
                                  BinaryPred pred);
  template<class ForwardIt1, class ForwardIt2>
    constexpr bool is_permutation(ForwardIt1 first1, ForwardIt1 last1,
                                  ForwardIt2 first2, ForwardIt2 last2);
  template<class ForwardIt1, class ForwardIt2, class BinaryPred>
    constexpr bool is_permutation(ForwardIt1 first1, ForwardIt1 last1,
                                  ForwardIt2 first2, ForwardIt2 last2,
                                  BinaryPred pred);
 
  namespace ranges {
    template<ForwardIterator I1, Sentinel<I1> S1, ForwardIterator I2,
             Sentinel<I2> S2, class Pred = ranges::equal_to, class Proj1 = identity,
             class Proj2 = identity>
      requires IndirectlyComparable<I1, I2, Pred, Proj1, Proj2>
      constexpr bool is_permutation(I1 first1, S1 last1, I2 first2, S2 last2,
                                    Pred pred = {},
                                    Proj1 proj1 = {}, Proj2 proj2 = {});
    template<ForwardRange R1, ForwardRange R2, class Pred = ranges::equal_to,
             class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyComparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
      constexpr bool is_permutation(R1&& r1, R2&& r2, Pred pred = {},
                                    Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  // 搜索（search）：
  template<class ForwardIt1, class ForwardIt2>
    constexpr ForwardIt1
      search(ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2);
  template<class ForwardIt1, class ForwardIt2, class BinaryPred>
    constexpr ForwardIt1
      search(ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2,
             BinaryPred pred);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    ForwardIt1
      search(ExecutionPolicy&& exec,
             ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class BinaryPred>
    ForwardIt1
      search(ExecutionPolicy&& exec,
             ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2,
             BinaryPred pred);
 
  namespace ranges {
    template<ForwardIterator I1, Sentinel<I1> S1, ForwardIterator I2,
             Sentinel<I2> S2, class Pred = ranges::equal_to,
             class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyComparable<I1, I2, Pred, Proj1, Proj2>
      constexpr subrange<I1>
        search(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},
               Proj1 proj1 = {}, Proj2 proj2 = {});
    template<ForwardRange R1, ForwardRange R2, class Pred = ranges::equal_to,
             class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyComparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
      constexpr safe_subrange_t<R1>
        search(R1&& r1, R2&& r2, Pred pred = {},
               Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  template<class ForwardIt, class Size, class T>
    constexpr ForwardIt
      search_n(ForwardIt first, ForwardIt last, Size count, const T& value);
  template<class ForwardIt, class Size, class T, class BinaryPred>
    constexpr ForwardIt
      search_n(ForwardIt first, ForwardIt last,
               Size count, const T& value, BinaryPred pred);
  template<class ExecutionPolicy, class ForwardIt, class Size, class T>
    ForwardIt
      search_n(ExecutionPolicy&& exec,
               ForwardIt first, ForwardIt last, Size count, const T& value);
  template<class ExecutionPolicy, class ForwardIt, class Size, class T, class BinaryPred>
    ForwardIt
      search_n(ExecutionPolicy&& exec,
               ForwardIt first, ForwardIt last,
               Size count, const T& value, BinaryPred pred);
 
  namespace ranges {
    template<ForwardIterator I, Sentinel<I> S, class T,
             class Pred = ranges::equal_to, class Proj = identity>
      requires IndirectlyComparable<I, const T*, Pred, Proj>
      constexpr subrange<I>
        search_n(I first, S last, iter_difference_t<I> count,
                 const T& value, Pred pred = {}, Proj proj = {});
    template<ForwardRange R, class T, class Pred = ranges::equal_to,
             class Proj = identity>
      requires IndirectlyComparable<iterator_t<R>, const T*, Pred, Proj>
      constexpr safe_subrange_t<R>
        search_n(R&& r, iter_difference_t<iterator_t<R>> count,
                 const T& value, Pred pred = {}, Proj proj = {});
  }
 
  template<class ForwardIt, class Searcher>
    constexpr ForwardIt
      search(ForwardIt first, ForwardIt last, const Searcher& searcher);
 
  // 修改序列的操作：
  // 复制（copy）：
  template<class InputIt, class OutputIt>
    constexpr OutputIt copy(InputIt first, InputIt last, OutputIt result);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    ForwardIt2 copy(ExecutionPolicy&& exec,
                    ForwardIt1 first, ForwardIt1 last, ForwardIt2 result);
 
  namespace ranges {
    template<class I, class O>
    struct copy_result {
      [[no_unique_address]] I in;
      [[no_unique_address]] O out;
 
      template<class I2, class O2>
        requires ConvertibleTo<const I&, I2> && ConvertibleTo<const O&, O2>
        operator copy_result<I2, O2>() const & {
          return {in, out};
        }
 
      template<class I2, class O2>
        requires ConvertibleTo<I, I2> && ConvertibleTo<O, O2>
        operator copy_result<I2, O2>() && {
          return {std::move(in), std::move(out)};
        }
    };
 
    template<InputIterator I, Sentinel<I> S, WeaklyIncrementable O>
      requires IndirectlyCopyable<I, O>
      constexpr copy_result<I, O>
        copy(I first, S last, O result);
    template<InputRange R, WeaklyIncrementable O>
      requires IndirectlyCopyable<iterator_t<R>, O>
      constexpr copy_result<safe_iterator_t<R>, O>
        copy(R&& r, O result);
  }
 
  template<class InputIt, class Size, class OutputIt>
    constexpr OutputIt copy_n(InputIt first, Size n, OutputIt result);
  template<class ExecutionPolicy, class ForwardIt1, class Size, class ForwardIt2>
    ForwardIt2 copy_n(ExecutionPolicy&& exec,
                      ForwardIt1 first, Size n, ForwardIt2 result);
 
  namespace ranges {
    template<class I, class O>
    using copy_n_result = copy_result<I, O>;
 
    template<InputIterator I, WeaklyIncrementable O>
      requires IndirectlyCopyable<I, O>
      constexpr copy_n_result<I, O>
        copy_n(I first, iter_difference_t<I> n, O result);
  }
 
  template<class InputIt, class OutputIt, class Pred>
    constexpr OutputIt copy_if(InputIt first, InputIt last, OutputIt result, Pred pred);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class Pred>
    ForwardIt2 copy_if(ExecutionPolicy&& exec,
                       ForwardIt1 first, ForwardIt1 last, ForwardIt2 result, Pred pred);
 
  namespace ranges {
    template<class I, class O>
    using copy_if_result = copy_result<I, O>;
 
    template<InputIterator I, Sentinel<I> S, WeaklyIncrementable O, class Proj = identity,
             IndirectUnaryPredicate<projected<I, Proj>> Pred>
      requires IndirectlyCopyable<I, O>
      constexpr copy_if_result<I, O>
        copy_if(I first, S last, O result, Pred pred, Proj proj = {});
    template<InputRange R, WeaklyIncrementable O, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      requires IndirectlyCopyable<iterator_t<R>, O>
      constexpr copy_if_result<safe_iterator_t<R>, O>
        copy_if(R&& r, O result, Pred pred, Proj proj = {});
  }
 
  template<class BidirectionalIt1, class BidirectionalIt2>
    constexpr BidirectionalIt2
      copy_backward(BidirectionalIt1 first, BidirectionalIt1 last,
                    BidirectionalIt2 result);
 
  namespace ranges {
    template<class I1, class I2>
    using copy_backward_result = copy_result<I1, I2>;
 
    template<BidirectionalIterator I1, Sentinel<I1> S1, BidirectionalIterator I2>
      requires IndirectlyCopyable<I1, I2>
      constexpr copy_backward_result<I1, I2>
        copy_backward(I1 first, S1 last, I2 result);
    template<BidirectionalRange R, BidirectionalIterator I>
      requires IndirectlyCopyable<iterator_t<R>, I>
      constexpr copy_backward_result<safe_iterator_t<R>, I>
        copy_backward(R&& r, I result);
  }
 
  // 移动（move）：
  template<class InputIt, class OutputIt>
    constexpr OutputIt move(InputIt first, InputIt last, OutputIt result);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    ForwardIt2 move(ExecutionPolicy&& exec,
                    ForwardIt1 first, ForwardIt1 last, ForwardIt2 result);
 
  namespace ranges {
    template<class I, class O>
    using move_result = copy_result<I, O>;
 
    template<InputIterator I, Sentinel<I> S, WeaklyIncrementable O>
      requires IndirectlyMovable<I, O>
      constexpr move_result<I, O>
        move(I first, S last, O result);
    template<InputRange R, WeaklyIncrementable O>
      requires IndirectlyMovable<iterator_t<R>, O>
      constexpr move_result<safe_iterator_t<R>, O>
        move(R&& r, O result);
  }
 
  template<class BidirectionalIt1, class BidirectionalIt2>
    constexpr BidirectionalIt2
      move_backward(BidirectionalIt1 first, BidirectionalIt1 last,
                    BidirectionalIt2 result);
 
  namespace ranges {
    template<class I1, class I2>
    using move_backward_result = copy_result<I1, I2>;
 
    template<BidirectionalIterator I1, Sentinel<I1> S1, BidirectionalIterator I2>
      requires IndirectlyMovable<I1, I2>
      constexpr move_backward_result<I1, I2>
        move_backward(I1 first, S1 last, I2 result);
    template<BidirectionalRange R, BidirectionalIterator I>
      requires IndirectlyMovable<iterator_t<R>, I>
      constexpr move_backward_result<safe_iterator_t<R>, I>
        move_backward(R&& r, I result);
  }
 
  // 交换（swap）：
  template<class ForwardIt1, class ForwardIt2>
    constexpr ForwardIt2 swap_ranges(ForwardIt1 first1, ForwardIt1 last1,
                                     ForwardIt2 first2);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    ForwardIt2 swap_ranges(ExecutionPolicy&& exec,
                           ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2);
 
  namespace ranges {
    template<class I1, class I2>
    using swap_ranges_result = mismatch_result<I1, I2>;
 
    template<InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2>
      requires IndirectlySwappable<I1, I2>
      constexpr swap_ranges_result<I1, I2>
        swap_ranges(I1 first1, S1 last1, I2 first2, S2 last2);
    template<InputRange R1, InputRange R2>
      requires IndirectlySwappable<iterator_t<R1>, iterator_t<R2>>
      constexpr swap_ranges_result<safe_iterator_t<R1>, safe_iterator_t<R2>>
        swap_ranges(R1&& r1, R2&& r2);
  }
 
  template<class ForwardIt1, class ForwardIt2>
    constexpr void iter_swap(ForwardIt1 a, ForwardIt2 b);
 
  // 变换（transform）：
  template<class InputIt, class OutputIt, class UnaryOperation>
    constexpr OutputIt
      transform(InputIt first1, InputIt last1, OutputIt result, UnaryOperation op);
  template<class InputIt1, class InputIt2, class OutputIt, class BinaryOperation>
    constexpr OutputIt
      transform(InputIt1 first1, InputIt1 last1, InputIt2 first2, OutputIt result,
                BinaryOperation binary_op);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class UnaryOperation>
    ForwardIt2
      transform(ExecutionPolicy&& exec,
                ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 result, UnaryOperation op);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class ForwardIt, class BinaryOperation>
    ForwardIt
      transform(ExecutionPolicy&& exec,
                ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt result,
                BinaryOperation binary_op);
 
  namespace ranges {
    template<class I, class O>
    using unary_transform_result = copy_result<I, O>;
 
    template<InputIterator I, Sentinel<I> S, WeaklyIncrementable O,
             CopyConstructible F, class Proj = identity>
      requires Writable<O, indirect_result_t<F&, projected<I, Proj>>>
      constexpr unary_transform_result<I, O>
        transform(I first1, S last1, O result, F op, Proj proj = {});
    template<InputRange R, WeaklyIncrementable O, CopyConstructible F,
             class Proj = identity>
      requires Writable<O, indirect_result_t<F&, projected<iterator_t<R>, Proj>>>
      constexpr unary_transform_result<safe_iterator_t<R>, O>
        transform(R&& r, O result, F op, Proj proj = {});
 
    template<class I1, class I2, class O>
    struct binary_transform_result {
      [[no_unique_address]] I1 in1;
      [[no_unique_address]] I2 in2;
      [[no_unique_address]] O  out;
 
      template<class II1, class II2, class OO>
        requires ConvertibleTo<const I1&, II1> &&
          ConvertibleTo<const I2&, II2> && ConvertibleTo<const O&, OO>
        operator binary_transform_result<II1, II2, OO>() const & {
          return {in1, in2, out};
        }
 
      template<class II1, class II2, class OO>
        requires ConvertibleTo<I1, II1> &&
          ConvertibleTo<I2, II2> && ConvertibleTo<O, OO>
        operator binary_transform_result<II1, II2, OO>() && {
          return {std::move(in1), std::move(in2), std::move(out)};
        }
    };
 
    template<InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
             WeaklyIncrementable O, CopyConstructible F, class Proj1 = identity,
             class Proj2 = identity>
      requires Writable<O, indirect_result_t<F&, projected<I1, Proj1>,
                                             projected<I2, Proj2>>>
      constexpr binary_transform_result<I1, I2, O>
        transform(I1 first1, S1 last1, I2 first2, S2 last2, O result,
                  F binary_op, Proj1 proj1 = {}, Proj2 proj2 = {});
    template<InputRange R1, InputRange R2, WeaklyIncrementable O,
             CopyConstructible F, class Proj1 = identity, class Proj2 = identity>
      requires Writable<O, indirect_result_t<F&, projected<iterator_t<R1>, Proj1>,
                                             projected<iterator_t<R2>, Proj2>>>
      constexpr binary_transform_result<safe_iterator_t<R1>, safe_iterator_t<R2>, O>
        transform(R1&& r1, R2&& r2, O result,
                  F binary_op, Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  // 替换（replace）：
  template<class ForwardIt, class T>
    constexpr void replace(ForwardIt first, ForwardIt last,
                           const T& old_value, const T& new_value);
  template<class ExecutionPolicy, class ForwardIt, class T>
    void replace(ExecutionPolicy&& exec,
                 ForwardIt first, ForwardIt last,
                 const T& old_value, const T& new_value);
  template<class ForwardIt, class Pred, class T>
    constexpr void replace_if(ForwardIt first, ForwardIt last,
                              Pred pred, const T& new_value);
  template<class ExecutionPolicy, class ForwardIt, class Pred, class T>
    void replace_if(ExecutionPolicy&& exec,
                    ForwardIt first, ForwardIt last,
                    Pred pred, const T& new_value);
 
  namespace ranges {
    template<InputIterator I, Sentinel<I> S, class T1, class T2, class Proj = identity>
      requires Writable<I, const T2&> &&
               IndirectRelation<ranges::equal_to, projected<I, Proj>, const T1*>
      constexpr I
        replace(I first, S last, const T1& old_value, const T2& new_value, Proj proj = {});
    template<InputRange R, class T1, class T2, class Proj = identity>
      requires Writable<iterator_t<R>, const T2&> &&
               IndirectRelation<ranges::equal_to, projected<iterator_t<R>, Proj>,
                 const T1*>
      constexpr safe_iterator_t<R>
        replace(R&& r, const T1& old_value, const T2& new_value, Proj proj = {});
    template<InputIterator I, Sentinel<I> S, class T, class Proj = identity,
             IndirectUnaryPredicate<projected<I, Proj>> Pred>
      requires Writable<I, const T&>
      constexpr I replace_if(I first, S last,
                             Pred pred, const T& new_value, Proj proj = {});
    template<InputRange R, class T, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      requires Writable<iterator_t<R>, const T&>
      constexpr safe_iterator_t<R>
        replace_if(R&& r, Pred pred, const T& new_value, Proj proj = {});
  }
 
  template<class InputIt, class OutputIt, class T>
    constexpr OutputIt replace_copy(InputIt first, InputIt last, OutputIt result,
                                    const T& old_value, const T& new_value);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class T>
    ForwardIt2 replace_copy(ExecutionPolicy&& exec,
                            ForwardIt1 first, ForwardIt1 last, ForwardIt2 result,
                            const T& old_value, const T& new_value);
  template<class InputIt, class OutputIt, class Pred, class T>
    constexpr OutputIt replace_copy_if(InputIt first, InputIt last, OutputIt result,
                                       Pred pred, const T& new_value);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class Pred, class T>
    ForwardIt2 replace_copy_if(ExecutionPolicy&& exec,
                               ForwardIt1 first, ForwardIt1 last, ForwardIt2 result,
                               Pred pred, const T& new_value);
 
  namespace ranges {
    template<class I, class O>
    using replace_copy_result = copy_result<I, O>;
 
    template<InputIterator I, Sentinel<I> S, class T1, class T2,
             OutputIterator<const T2&> O, class Proj = identity>
      requires IndirectlyCopyable<I, O> &&
               IndirectRelation<ranges::equal_to, projected<I, Proj>, const T1*>
      constexpr replace_copy_result<I, O>
        replace_copy(I first, S last, O result, const T1& old_value, const T2& new_value,
                     Proj proj = {});
    template<InputRange R, class T1, class T2, OutputIterator<const T2&> O,
             class Proj = identity>
      requires IndirectlyCopyable<iterator_t<R>, O> &&
               IndirectRelation<ranges::equal_to, projected<iterator_t<R>, Proj>,
                 const T1*>
      constexpr replace_copy_result<safe_iterator_t<R>, O>
        replace_copy(R&& r, O result, const T1& old_value, const T2& new_value,
                     Proj proj = {});
 
    template<class I, class O>
    using replace_copy_if_result = copy_result<I, O>;
 
    template<InputIterator I, Sentinel<I> S, class T, OutputIterator<const T&> O,
             class Proj = identity, IndirectUnaryPredicate<projected<I, Proj>> Pred>
      requires IndirectlyCopyable<I, O>
      constexpr replace_copy_if_result<I, O>
        replace_copy_if(I first, S last, O result, Pred pred, const T& new_value,
                        Proj proj = {});
    template<InputRange R, class T, OutputIterator<const T&> O, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      requires IndirectlyCopyable<iterator_t<R>, O>
      constexpr replace_copy_if_result<safe_iterator_t<R>, O>
        replace_copy_if(R&& r, O result, Pred pred, const T& new_value,
                        Proj proj = {});
  }
 
  // 填充（fill）：
  template<class ForwardIt, class T>
    constexpr void fill(ForwardIt first, ForwardIt last, const T& value);
  template<class ExecutionPolicy, class ForwardIt, class T>
    void fill(ExecutionPolicy&& exec,
              ForwardIt first, ForwardIt last, const T& value);
  template<class OutputIt, class Size, class T>
    constexpr OutputIt fill_n(OutputIt first, Size n, const T& value);
  template<class ExecutionPolicy, class ForwardIt, class Size, class T>
    ForwardIt fill_n(ExecutionPolicy&& exec,
                     ForwardIt first, Size n, const T& value);
 
  namespace ranges {
    template<class T, OutputIterator<const T&> O, Sentinel<O> S>
      constexpr O fill(O first, S last, const T& value);
    template<class T, OutputRange<const T&> R>
      constexpr safe_iterator_t<R> fill(R&& r, const T& value);
    template<class T, OutputIterator<const T&> O>
      constexpr O fill_n(O first, iter_difference_t<O> n, const T& value);
  }
 
  // 生成（generate）：
  template<class ForwardIt, class Generator>
    constexpr void generate(ForwardIt first, ForwardIt last, Generator gen);
  template<class ExecutionPolicy, class ForwardIt, class Generator>
    void generate(ExecutionPolicy&& exec,
                  ForwardIt first, ForwardIt last, Generator gen);
  template<class OutputIt, class Size, class Generator>
    constexpr OutputIt generate_n(OutputIt first, Size n, Generator gen);
  template<class ExecutionPolicy, class ForwardIt, class Size, class Generator>
    ForwardIt generate_n(ExecutionPolicy&& exec,
                         ForwardIt first, Size n, Generator gen);
 
  namespace ranges {
    template<Iterator O, Sentinel<O> S, CopyConstructible F>
      requires Invocable<F&> && Writable<O, invoke_result_t<F&>>
      constexpr O generate(O first, S last, F gen);
    template<class R, CopyConstructible F>
      requires Invocable<F&> && OutputRange<R, invoke_result_t<F&>>
      constexpr safe_iterator_t<R> generate(R&& r, F gen);
    template<Iterator O, CopyConstructible F>
      requires Invocable<F&> && Writable<O, invoke_result_t<F&>>
      constexpr O generate_n(O first, iter_difference_t<O> n, F gen);
  }
 
  // 移除（remove）：
  template<class ForwardIt, class T>
    constexpr ForwardIt remove(ForwardIt first, ForwardIt last, const T& value);
  template<class ExecutionPolicy, class ForwardIt, class T>
    ForwardIt remove(ExecutionPolicy&& exec,
                     ForwardIt first, ForwardIt last, const T& value);
  template<class ForwardIt, class Pred>
    constexpr ForwardIt remove_if(ForwardIt first, ForwardIt last, Pred pred);
  template<class ExecutionPolicy, class ForwardIt, class Pred>
    ForwardIt remove_if(ExecutionPolicy&& exec,
                        ForwardIt first, ForwardIt last, Pred pred);
 
  namespace ranges {
    template<Permutable I, Sentinel<I> S, class T, class Proj = identity>
      requires IndirectRelation<ranges::equal_to, projected<I, Proj>, const T*>
      constexpr I remove(I first, S last, const T& value, Proj proj = {});
    template<ForwardRange R, class T, class Proj = identity>
      requires Permutable<iterator_t<R>> &&
               IndirectRelation<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
      constexpr safe_iterator_t<R>
        remove(R&& r, const T& value, Proj proj = {});
    template<Permutable I, Sentinel<I> S, class Proj = identity,
             IndirectUnaryPredicate<projected<I, Proj>> Pred>
      constexpr I remove_if(I first, S last, Pred pred, Proj proj = {});
    template<ForwardRange R, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      requires Permutable<iterator_t<R>>
      constexpr safe_iterator_t<R>
        remove_if(R&& r, Pred pred, Proj proj = {});
  }
 
  template<class InputIt, class OutputIt, class T>
    constexpr OutputIt
      remove_copy(InputIt first, InputIt last, OutputIt result, const T& value);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class T>
    ForwardIt2
      remove_copy(ExecutionPolicy&& exec,
                  ForwardIt1 first, ForwardIt1 last, ForwardIt2 result, const T& value);
  template<class InputIt, class OutputIt, class Pred>
    constexpr OutputIt
      remove_copy_if(InputIt first, InputIt last, OutputIt result, Pred pred);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class Pred>
    ForwardIt2
      remove_copy_if(ExecutionPolicy&& exec,
                     ForwardIt1 first, ForwardIt1 last, ForwardIt2 result, Pred pred);
 
  namespace ranges {
    template<class I, class O>
    using remove_copy_result = copy_result<I, O>;
 
    template<InputIterator I, Sentinel<I> S, WeaklyIncrementable O, class T,
             class Proj = identity>
      requires IndirectlyCopyable<I, O> &&
               IndirectRelation<ranges::equal_to, projected<I, Proj>, const T*>
      constexpr remove_copy_result<I, O>
        remove_copy(I first, S last, O result, const T& value, Proj proj = {});
    template<InputRange R, WeaklyIncrementable O, class T, class Proj = identity>
      requires IndirectlyCopyable<iterator_t<R>, O> &&
               IndirectRelation<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*>
      constexpr remove_copy_result<safe_iterator_t<R>, O>
        remove_copy(R&& r, O result, const T& value, Proj proj = {});
 
    template<class I, class O>
    using remove_copy_if_result = copy_result<I, O>;
 
    template<InputIterator I, Sentinel<I> S, WeaklyIncrementable O,
             class Proj = identity, IndirectUnaryPredicate<projected<I, Proj>> Pred>
      requires IndirectlyCopyable<I, O>
      constexpr remove_copy_if_result<I, O>
        remove_copy_if(I first, S last, O result, Pred pred, Proj proj = {});
    template<InputRange R, WeaklyIncrementable O, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      requires IndirectlyCopyable<iterator_t<R>, O>
      constexpr remove_copy_if_result<safe_iterator_t<R>, O>
        remove_copy_if(R&& r, O result, Pred pred, Proj proj = {});
  }
 
  // 唯一（unique）：
  template<class ForwardIt>
    constexpr ForwardIt unique(ForwardIt first, ForwardIt last);
  template<class ForwardIt, class BinaryPred>
    constexpr ForwardIt unique(ForwardIt first, ForwardIt last, BinaryPred pred);
  template<class ExecutionPolicy, class ForwardIt>
    ForwardIt unique(ExecutionPolicy&& exec,
                     ForwardIt first, ForwardIt last);
  template<class ExecutionPolicy, class ForwardIt, class BinaryPred>
    ForwardIt unique(ExecutionPolicy&& exec,
                     ForwardIt first, ForwardIt last, BinaryPred pred);
 
  namespace ranges {
    template<Permutable I, Sentinel<I> S, class Proj = identity,
             IndirectRelation<projected<I, Proj>> C = ranges::equal_to>
      constexpr I unique(I first, S last, C comp = {}, Proj proj = {});
    template<ForwardRange R, class Proj = identity,
             IndirectRelation<projected<iterator_t<R>, Proj>> C = ranges::equal_to>
      requires Permutable<iterator_t<R>>
      constexpr safe_iterator_t<R>
        unique(R&& r, C comp = {}, Proj proj = {});
  }
 
  template<class InputIt, class OutputIt>
    constexpr OutputIt
      unique_copy(InputIt first, InputIt last, OutputIt result);
  template<class InputIt, class OutputIt, class BinaryPred>
    constexpr OutputIt
      unique_copy(InputIt first, InputIt last, OutputIt result, BinaryPred pred);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    ForwardIt2
      unique_copy(ExecutionPolicy&& exec,
                  ForwardIt1 first, ForwardIt1 last, ForwardIt2 result);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class BinaryPred>
    ForwardIt2
      unique_copy(ExecutionPolicy&& exec,
                  ForwardIt1 first, ForwardIt1 last, ForwardIt2 result, BinaryPred pred);
 
  namespace ranges {
    template<class I, class O>
    using unique_copy_result = copy_result<I, O>;
 
    template<InputIterator I, Sentinel<I> S, WeaklyIncrementable O,
             class Proj = identity,
             IndirectRelation<projected<I, Proj>> C = ranges::equal_to>
      requires IndirectlyCopyable<I, O> &&
               (ForwardIterator<I> ||
                (InputIterator<O> && Same<iter_value_t<I>, iter_value_t<O>>) ||
                IndirectlyCopyableStorable<I, O>)
      constexpr unique_copy_result<I, O>
        unique_copy(I first, S last, O result, C comp = {}, Proj proj = {});
    template<InputRange R, WeaklyIncrementable O, class Proj = identity,
             IndirectRelation<projected<iterator_t<R>, Proj>> C = ranges::equal_to>
      requires IndirectlyCopyable<iterator_t<R>, O> &&
               (ForwardIterator<iterator_t<R>> ||
                (InputIterator<O> && Same<iter_value_t<iterator_t<R>>, iter_value_t<O>>) ||
                IndirectlyCopyableStorable<iterator_t<R>, O>)
      constexpr unique_copy_result<safe_iterator_t<R>, O>
        unique_copy(R&& r, O result, C comp = {}, Proj proj = {});
  }
 
  // 反转（reverse）：
  template<class BidirectionalIt>
    constexpr void reverse(BidirectionalIt first, BidirectionalIt last);
  template<class ExecutionPolicy, class BidirectionalIt>
    void reverse(ExecutionPolicy&& exec,
                 BidirectionalIt first, BidirectionalIt last);
 
  namespace ranges {
    template<BidirectionalIterator I, Sentinel<I> S>
      requires Permutable<I>
      constexpr I reverse(I first, S last);
    template<BidirectionalRange R>
      requires Permutable<iterator_t<R>>
      constexpr safe_iterator_t<R> reverse(R&& r);
  }
 
  template<class BidirectionalIt, class OutputIt>
    constexpr OutputIt
      reverse_copy(BidirectionalIt first, BidirectionalIt last, OutputIt result);
  template<class ExecutionPolicy, class BidirectionalIt, class ForwardIt>
    ForwardIt
      reverse_copy(ExecutionPolicy&& exec,
                   BidirectionalIt first, BidirectionalIt last, ForwardIt result);
 
  namespace ranges {
    template<class I, class O>
    using reverse_copy_result = copy_result<I, O>;
 
    template<BidirectionalIterator I, Sentinel<I> S, WeaklyIncrementable O>
      requires IndirectlyCopyable<I, O>
      constexpr reverse_copy_result<I, O>
        reverse_copy(I first, S last, O result);
    template<BidirectionalRange R, WeaklyIncrementable O>
      requires IndirectlyCopyable<iterator_t<R>, O>
      constexpr reverse_copy_result<safe_iterator_t<R>, O>
        reverse_copy(R&& r, O result);
  }
 
  // 旋转（rotate）：
  template<class ForwardIt>
    constexpr ForwardIt rotate(ForwardIt first, ForwardIt middle, ForwardIt last);
  template<class ExecutionPolicy, class ForwardIt>
    ForwardIt rotate(ExecutionPolicy&& exec,
                     ForwardIt first, ForwardIt middle, ForwardIt last);
 
  namespace ranges {
    template<Permutable I, Sentinel<I> S>
      constexpr subrange<I> rotate(I first, I middle, S last);
    template<ForwardRange R>
      requires Permutable<iterator_t<R>>
      constexpr safe_subrange_t<R> rotate(R&& r, iterator_t<R> middle);
  }
 
  template<class ForwardIt, class OutputIt>
    constexpr OutputIt
      rotate_copy(ForwardIt first, ForwardIt middle, ForwardIt last, OutputIt result);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    ForwardIt2
      rotate_copy(ExecutionPolicy&& exec,
                  ForwardIt1 first, ForwardIt1 middle, ForwardIt1 last, ForwardIt2 result);
 
  namespace ranges {
    template<class I, class O>
    using rotate_copy_result = copy_result<I, O>;
 
    template<ForwardIterator I, Sentinel<I> S, WeaklyIncrementable O>
      requires IndirectlyCopyable<I, O>
      constexpr rotate_copy_result<I, O>
        rotate_copy(I first, I middle, S last, O result);
    template<ForwardRange R, WeaklyIncrementable O>
      requires IndirectlyCopyable<iterator_t<R>, O>
      constexpr rotate_copy_result<safe_iterator_t<R>, O>
        rotate_copy(R&& r, iterator_t<R> middle, O result);
  }
 
  // 采样（sample）：
  template<class PopulationIt, class SampleIt,
           class Distance, class UniformRndBitGen>
    SampleIt sample(PopulationIt first, PopulationIt last, SampleIt out, Distance n,
                    UniformRndBitGen&& g);
 
  // 混洗（shuffle）：
  template<class RandomAccessIt, class UniformRndBitGen>
    void shuffle(RandomAccessIt first, RandomAccessIt last, UniformRndBitGen&& g);
 
  namespace ranges {
    template<RandomAccessIterator I, Sentinel<I> S, class Gen>
      requires Permutable<I> &&
               UniformRandomBitGenerator<remove_reference_t<Gen>> &&
               ConvertibleTo<invoke_result_t<Gen&>, iter_difference_t<I>>
      I shuffle(I first, S last, Gen&& g);
    template<RandomAccessRange R, class Gen>
      requires Permutable<iterator_t<R>> &&
               UniformRandomBitGenerator<remove_reference_t<Gen>> &&
               ConvertibleTo<invoke_result_t<Gen&>, iter_difference_t<iterator_t<R>>>
      safe_iterator_t<R> shuffle(R&& r, Gen&& g);
  }
 
  // 移位（shift）：
  template<class ForwardIt>
    constexpr ForwardIt
      shift_left(ForwardIt first, ForwardIt last,
                 typename iterator_traits<ForwardIt>::difference_type n);
  template<class ExecutionPolicy, class ForwardIt>
    ForwardIt
      shift_left(ExecutionPolicy&& exec,
                 ForwardIt first, ForwardIt last,
                 typename iterator_traits<ForwardIt>::difference_type n);
  template<class ForwardIt>
    constexpr ForwardIt
      shift_right(ForwardIt first, ForwardIt last,
                  typename iterator_traits<ForwardIt>::difference_type n);
  template<class ExecutionPolicy, class ForwardIt>
    ForwardIt
      shift_right(ExecutionPolicy&& exec,
                  ForwardIt first, ForwardIt last,
                  typename iterator_traits<ForwardIt>::difference_type n);
 
  // 排序与相关操作：
  // 排序：
  template<class RandomAccessIt>
    constexpr void sort(RandomAccessIt first, RandomAccessIt last);
  template<class RandomAccessIt, class Compare>
    constexpr void sort(RandomAccessIt first, RandomAccessIt last, Compare comp);
  template<class ExecutionPolicy, class RandomAccessIt>
    void sort(ExecutionPolicy&& exec,
              RandomAccessIt first, RandomAccessIt last);
  template<class ExecutionPolicy, class RandomAccessIt, class Compare>
    void sort(ExecutionPolicy&& exec,
              RandomAccessIt first, RandomAccessIt last, Compare comp);
 
  namespace ranges {
    template<RandomAccessIterator I, Sentinel<I> S, class Comp = ranges::less,
             class Proj = identity>
      requires Sortable<I, Comp, Proj>
      constexpr I
        sort(I first, S last, Comp comp = {}, Proj proj = {});
    template<RandomAccessRange R, class Comp = ranges::less, class Proj = identity>
      requires Sortable<iterator_t<R>, Comp, Proj>
      constexpr safe_iterator_t<R>
        sort(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  template<class RandomAccessIt>
    void stable_sort(RandomAccessIt first, RandomAccessIt last);
  template<class RandomAccessIt, class Compare>
    void stable_sort(RandomAccessIt first, RandomAccessIt last, Compare comp);
  template<class ExecutionPolicy, class RandomAccessIt>
    void stable_sort(ExecutionPolicy&& exec,
                     RandomAccessIt first, RandomAccessIt last);
  template<class ExecutionPolicy, class RandomAccessIt, class Compare>
    void stable_sort(ExecutionPolicy&& exec,
                     RandomAccessIt first, RandomAccessIt last, Compare comp);
 
  namespace ranges {
    template<RandomAccessIterator I, Sentinel<I> S, class Comp = ranges::less,
             class Proj = identity>
      requires Sortable<I, Comp, Proj>
      I stable_sort(I first, S last, Comp comp = {}, Proj proj = {});
    template<RandomAccessRange R, class Comp = ranges::less, class Proj = identity>
      requires Sortable<iterator_t<R>, Comp, Proj>
      safe_iterator_t<R>
        stable_sort(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  template<class RandomAccessIt>
    constexpr void partial_sort(RandomAccessIt first, RandomAccessIt middle,
                                RandomAccessIt last);
  template<class RandomAccessIt, class Compare>
    constexpr void partial_sort(RandomAccessIt first, RandomAccessIt middle,
                                RandomAccessIt last, Compare comp);
  template<class ExecutionPolicy, class RandomAccessIt>
    void partial_sort(ExecutionPolicy&& exec,
                      RandomAccessIt first, RandomAccessIt middle, RandomAccessIt last);
  template<class ExecutionPolicy, class RandomAccessIt, class Compare>
    void partial_sort(ExecutionPolicy&& exec,
                      RandomAccessIt first, RandomAccessIt middle, RandomAccessIt last,
                      Compare comp);
 
  namespace ranges {
    template<RandomAccessIterator I, Sentinel<I> S, class Comp = ranges::less,
             class Proj = identity>
      requires Sortable<I, Comp, Proj>
      constexpr I
        partial_sort(I first, I middle, S last, Comp comp = {}, Proj proj = {});
    template<RandomAccessRange R, class Comp = ranges::less, class Proj = identity>
      requires Sortable<iterator_t<R>, Comp, Proj>
      constexpr safe_iterator_t<R>
        partial_sort(R&& r, iterator_t<R> middle, Comp comp = {},
                     Proj proj = {});
  }
 
  template<class InputIt, class RandomAccessIt>
    constexpr RandomAccessIt
      partial_sort_copy(InputIt first, InputIt last,
                        RandomAccessIt result_first, RandomAccessIt result_last);
  template<class InputIt, class RandomAccessIt, class Compare>
    constexpr RandomAccessIt
      partial_sort_copy(InputIt first, InputIt last,
                        RandomAccessIt result_first, RandomAccessIt result_last,
                        Compare comp);
  template<class ExecutionPolicy, class ForwardIt, class RandomAccessIt>
    RandomAccessIt
      partial_sort_copy(ExecutionPolicy&& exec, 
                        ForwardIt first, ForwardIt last,
                        RandomAccessIt result_first, RandomAccessIt result_last);
  template<class ExecutionPolicy, class ForwardIt, class RandomAccessIt, class Compare>
    RandomAccessIt
      partial_sort_copy(ExecutionPolicy&& exec, 
                        ForwardIt first, ForwardIt last,
                        RandomAccessIt result_first, RandomAccessIt result_last,
                        Compare comp);
 
  namespace ranges {
    template<InputIterator I1, Sentinel<I1> S1, RandomAccessIterator I2, Sentinel<I2> S2,
             class Comp = ranges::less, class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyCopyable<I1, I2> && Sortable<I2, Comp, Proj2> &&
               IndirectStrictWeakOrder<Comp, projected<I1, Proj1>, projected<I2, Proj2>>
      constexpr I2
        partial_sort_copy(I1 first, S1 last, I2 result_first, S2 result_last,
                          Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {});
    template<InputRange R1, RandomAccessRange R2, class Comp = ranges::less,
             class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyCopyable<iterator_t<R1>, iterator_t<R2>> &&
               Sortable<iterator_t<R2>, Comp, Proj2> &&
               IndirectStrictWeakOrder<Comp, projected<iterator_t<R1>, Proj1>,
                                       projected<iterator_t<R2>, Proj2>>
      constexpr safe_iterator_t<R2>
        partial_sort_copy(R1&& r, R2&& result_r, Comp comp = {},
                          Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  template<class ForwardIt>
    constexpr bool is_sorted(ForwardIt first, ForwardIt last);
  template<class ForwardIt, class Compare>
    constexpr bool is_sorted(ForwardIt first, ForwardIt last, Compare comp);
  template<class ExecutionPolicy, class ForwardIt>
    bool is_sorted(ExecutionPolicy&& exec,
                   ForwardIt first, ForwardIt last);
  template<class ExecutionPolicy, class ForwardIt, class Compare>
    bool is_sorted(ExecutionPolicy&& exec,
                   ForwardIt first, ForwardIt last, Compare comp);
 
  namespace ranges {
    template<ForwardIterator I, Sentinel<I> S, class Proj = identity,
             IndirectStrictWeakOrder<projected<I, Proj>> Comp = ranges::less>
      constexpr bool is_sorted(I first, S last, Comp comp = {}, Proj proj = {});
    template<ForwardRange R, class Proj = identity,
             IndirectStrictWeakOrder<projected<iterator_t<R>, Proj>> Comp = ranges::less>
      constexpr bool is_sorted(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  template<class ForwardIt>
    constexpr ForwardIt
      is_sorted_until(ForwardIt first, ForwardIt last);
  template<class ForwardIt, class Compare>
    constexpr ForwardIt
      is_sorted_until(ForwardIt first, ForwardIt last, Compare comp);
  template<class ExecutionPolicy, class ForwardIt>
    ForwardIt
      is_sorted_until(ExecutionPolicy&& exec,
                      ForwardIt first, ForwardIt last);
  template<class ExecutionPolicy, class ForwardIt, class Compare>
    ForwardIt
      is_sorted_until(ExecutionPolicy&& exec,
                      ForwardIt first, ForwardIt last, Compare comp);
 
  namespace ranges {
    template<ForwardIterator I, Sentinel<I> S, class Proj = identity,
             IndirectStrictWeakOrder<projected<I, Proj>> Comp = ranges::less>
      constexpr I is_sorted_until(I first, S last, Comp comp = {}, Proj proj = {});
    template<ForwardRange R, class Proj = identity,
             IndirectStrictWeakOrder<projected<iterator_t<R>, Proj>> Comp = ranges::less>
      constexpr safe_iterator_t<R>
        is_sorted_until(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  // 第 N 元素：
  template<class RandomAccessIt>
    constexpr void nth_element(RandomAccessIt first, RandomAccessIt nth,
                               RandomAccessIt last);
  template<class RandomAccessIt, class Compare>
    constexpr void nth_element(RandomAccessIt first, RandomAccessIt nth,
                               RandomAccessIt last, Compare comp);
  template<class ExecutionPolicy, class RandomAccessIt>
    void nth_element(ExecutionPolicy&& exec,
                     RandomAccessIt first, RandomAccessIt nth,
                     RandomAccessIt last);
  template<class ExecutionPolicy, class RandomAccessIt, class Compare>
    void nth_element(ExecutionPolicy&& exec,
                     RandomAccessIt first, RandomAccessIt nth,
                     RandomAccessIt last, Compare comp);
 
  namespace ranges {
    template<RandomAccessIterator I, Sentinel<I> S, class Comp = ranges::less,
             class Proj = identity>
      requires Sortable<I, Comp, Proj>
      constexpr I
        nth_element(I first, I nth, S last, Comp comp = {}, Proj proj = {});
    template<RandomAccessRange R, class Comp = ranges::less, class Proj = identity>
      requires Sortable<iterator_t<R>, Comp, Proj>
      constexpr safe_iterator_t<R>
        nth_element(R&& r, iterator_t<R> nth, Comp comp = {}, Proj proj = {});
  }
 
  // 二分搜索：
  template<class ForwardIt, class T>
    constexpr ForwardIt
      lower_bound(ForwardIt first, ForwardIt last, const T& value);
  template<class ForwardIt, class T, class Compare>
    constexpr ForwardIt
      lower_bound(ForwardIt first, ForwardIt last, const T& value, Compare comp);
 
  namespace ranges {
    template<ForwardIterator I, Sentinel<I> S, class T, class Proj = identity,
             IndirectStrictWeakOrder<const T*, projected<I, Proj>> Comp = ranges::less>
      constexpr I lower_bound(I first, S last, const T& value, Comp comp = {},
                              Proj proj = {});
    template<ForwardRange R, class T, class Proj = identity,
             IndirectStrictWeakOrder<const T*, projected<iterator_t<R>, Proj>> Comp =
               ranges::less>
      constexpr safe_iterator_t<R>
        lower_bound(R&& r, const T& value, Comp comp = {}, Proj proj = {});
  }
 
  template<class ForwardIt, class T>
    constexpr ForwardIt
      upper_bound(ForwardIt first, ForwardIt last, const T& value);
  template<class ForwardIt, class T, class Compare>
    constexpr ForwardIt
      upper_bound(ForwardIt first, ForwardIt last, const T& value, Compare comp);
 
  namespace ranges {
    template<ForwardIterator I, Sentinel<I> S, class T, class Proj = identity,
             IndirectStrictWeakOrder<const T*, projected<I, Proj>> Comp = ranges::less>
      constexpr I upper_bound(I first, S last,
                              const T& value, Comp comp = {}, Proj proj = {});
    template<ForwardRange R, class T, class Proj = identity,
             IndirectStrictWeakOrder<const T*, projected<iterator_t<R>, Proj>> Comp =
               ranges::less>
      constexpr safe_iterator_t<R>
        upper_bound(R&& r, const T& value, Comp comp = {}, Proj proj = {});
  }
 
  template<class ForwardIt, class T>
    constexpr pair<ForwardIt, ForwardIt>
      equal_range(ForwardIt first, ForwardIt last, const T& value);
  template<class ForwardIt, class T, class Compare>
    constexpr pair<ForwardIt, ForwardIt>
      equal_range(ForwardIt first, ForwardIt last, const T& value, Compare comp);
 
  namespace ranges {
    template<ForwardIterator I, Sentinel<I> S, class T, class Proj = identity,
             IndirectStrictWeakOrder<const T*, projected<I, Proj>> Comp = ranges::less>
      constexpr subrange<I>
        equal_range(I first, S last, const T& value, Comp comp = {}, Proj proj = {});
    template<ForwardRange R, class T, class Proj = identity,
             IndirectStrictWeakOrder<const T*, projected<iterator_t<R>, Proj>> Comp =
               ranges::less>
      constexpr safe_subrange_t<R>
        equal_range(R&& r, const T& value, Comp comp = {}, Proj proj = {});
  }
 
  template<class ForwardIt, class T>
    constexpr bool
      binary_search(ForwardIt first, ForwardIt last, const T& value);
  template<class ForwardIt, class T, class Compare>
    constexpr bool
      binary_search(ForwardIt first, ForwardIt last, const T& value, Compare comp);
 
  namespace ranges {
    template<ForwardIterator I, Sentinel<I> S, class T, class Proj = identity,
             IndirectStrictWeakOrder<const T*, projected<I, Proj>> Comp = ranges::less>
      constexpr bool binary_search(I first, S last, const T& value, Comp comp = {},
                                   Proj proj = {});
    template<ForwardRange R, class T, class Proj = identity,
             IndirectStrictWeakOrder<const T*, projected<iterator_t<R>, Proj>> Comp =
               ranges::less>
      constexpr bool binary_search(R&& r, const T& value, Comp comp = {},
                                   Proj proj = {});
  }
 
  // 划分（partition）：
  template<class InputIt, class Pred>
    constexpr bool is_partitioned(InputIt first, InputIt last, Pred pred);
  template<class ExecutionPolicy, class ForwardIt, class Pred>
    bool is_partitioned(ExecutionPolicy&& exec,
                        ForwardIt first, ForwardIt last, Pred pred);
 
  namespace ranges {
    template<InputIterator I, Sentinel<I> S, class Proj = identity,
             IndirectUnaryPredicate<projected<I, Proj>> Pred>
      constexpr bool is_partitioned(I first, S last, Pred pred, Proj proj = {});
    template<InputRange R, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      constexpr bool is_partitioned(R&& r, Pred pred, Proj proj = {});
  }
 
  template<class ForwardIt, class Pred>
    constexpr ForwardIt partition(ForwardIt first, ForwardIt last, Pred pred);
  template<class ExecutionPolicy, class ForwardIt, class Pred>
    ForwardIt partition(ExecutionPolicy&& exec,
                        ForwardIt first, ForwardIt last, Pred pred);
 
  namespace ranges {
    template<Permutable I, Sentinel<I> S, class Proj = identity,
             IndirectUnaryPredicate<projected<I, Proj>> Pred>
      constexpr I
        partition(I first, S last, Pred pred, Proj proj = {});
    template<ForwardRange R, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      requires Permutable<iterator_t<R>>
      constexpr safe_iterator_t<R>
        partition(R&& r, Pred pred, Proj proj = {});
  }
 
  template<class BidirectionalIt, class Pred>
    BidirectionalIt stable_partition(BidirectionalIt first, BidirectionalIt last,
                                     Pred pred);
  template<class ExecutionPolicy, class BidirectionalIt, class Pred>
    BidirectionalIt stable_partition(ExecutionPolicy&& exec,
                                     BidirectionalIt first, BidirectionalIt last,
                                     Pred pred);
 
  namespace ranges {
    template<BidirectionalIterator I, Sentinel<I> S, class Proj = identity,
             IndirectUnaryPredicate<projected<I, Proj>> Pred>
      requires Permutable<I>
      I stable_partition(I first, S last, Pred pred, Proj proj = {});
    template<BidirectionalRange R, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      requires Permutable<iterator_t<R>>
      safe_iterator_t<R> stable_partition(R&& r, Pred pred, Proj proj = {});
  }
 
  template<class InputIt, class OutputIt1, class OutputIt2, class Pred>
    constexpr pair<OutputIt1, OutputIt2>
      partition_copy(InputIt first, InputIt last, OutputIt1 out_true, OutputIt2 out_false,
                     Pred pred);
  template<class ExecutionPolicy, class ForwardIt, class ForwardIt1,
           class ForwardIt2, class Pred>
    pair<ForwardIt1, ForwardIt2>
      partition_copy(ExecutionPolicy&& exec,
                     ForwardIt first, ForwardIt last,
                     ForwardIt1 out_true, ForwardIt2 out_false,
                     Pred pred);
 
  namespace ranges {
    template<class I, class O1, class O2>
    struct partition_copy_result {
      [[no_unique_address]] I  in;
      [[no_unique_address]] O1 out1;
      [[no_unique_address]] O2 out2;
 
      template<class II, class OO1, class OO2>
        requires ConvertibleTo<const I&, II> &&
          ConvertibleTo<const O1&, OO1> && ConvertibleTo<const O2&, OO2>
        operator partition_copy_result<II, OO1, OO2>() const & {
          return {in, out1, out2};
        }
 
      template<class II, class OO1, class OO2>
        requires ConvertibleTo<I, II> &&
          ConvertibleTo<O1, OO1> && ConvertibleTo<O2, OO2>
        operator partition_copy_result<II, OO1, OO2>() && {
          return {std::move(in), std::move(out1), std::move(out2)};
        }
    };
 
    template<InputIterator I, Sentinel<I> S,
             WeaklyIncrementable O1, WeaklyIncrementable O2,
             class Proj = identity, IndirectUnaryPredicate<projected<I, Proj>> Pred>
      requires IndirectlyCopyable<I, O1> && IndirectlyCopyable<I, O2>
      constexpr partition_copy_result<I, O1, O2>
        partition_copy(I first, S last, O1 out_true, O2 out_false, Pred pred,
                       Proj proj = {});
    template<InputRange R, WeaklyIncrementable O1, WeaklyIncrementable O2,
             class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      requires IndirectlyCopyable<iterator_t<R>, O1> &&
               IndirectlyCopyable<iterator_t<R>, O2>
      constexpr partition_copy_result<safe_iterator_t<R>, O1, O2>
        partition_copy(R&& r, O1 out_true, O2 out_false, Pred pred, Proj proj = {});
  }
 
  template<class ForwardIt, class Pred>
    constexpr ForwardIt
      partition_point(ForwardIt first, ForwardIt last, Pred pred);
 
  namespace ranges {
    template<ForwardIterator I, Sentinel<I> S, class Proj = identity,
             IndirectUnaryPredicate<projected<I, Proj>> Pred>
      constexpr I partition_point(I first, S last, Pred pred, Proj proj = {});
    template<ForwardRange R, class Proj = identity,
             IndirectUnaryPredicate<projected<iterator_t<R>, Proj>> Pred>
      constexpr safe_iterator_t<R>
        partition_point(R&& r, Pred pred, Proj proj = {});
  }
 
  // 归并（merge）：
  template<class InputIt1, class InputIt2, class OutputIt>
    constexpr OutputIt
      merge(InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2,
            OutputIt result);
  template<class InputIt1, class InputIt2, class OutputIt, class Compare>
    constexpr OutputIt
      merge(InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2,
            OutputIt result, Compare comp);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class ForwardIt>
    ForwardIt
      merge(ExecutionPolicy&& exec,
            ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2,
            ForwardIt result);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class ForwardIt, class Compare>
    ForwardIt
      merge(ExecutionPolicy&& exec,
            ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2,
            ForwardIt result, Compare comp);
 
  namespace ranges {
    template<class I1, class I2, class O>
    using merge_result = binary_transform_result<I1, I2, O>;
 
    template<InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
             WeaklyIncrementable O, class Comp = ranges::less, class Proj1 = identity,
             class Proj2 = identity>
      requires Mergeable<I1, I2, O, Comp, Proj1, Proj2>
      constexpr merge_result<I1, I2, O>
        merge(I1 first1, S1 last1, I2 first2, S2 last2, O result,
              Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {});
    template<InputRange R1, InputRange R2, WeaklyIncrementable O,
             class Comp = ranges::less, class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<iterator_t<R1>, iterator_t<R2>, O, Comp, Proj1, Proj2>
      constexpr merge_result<safe_iterator_t<R1>, safe_iterator_t<R2>, O>
        merge(R1&& r1, R2&& r2, O result,
              Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  template<class BidirectionalIt>
    void inplace_merge(BidirectionalIt first,
                       BidirectionalIt middle,
                       BidirectionalIt last);
  template<class BidirectionalIt, class Compare>
    void inplace_merge(BidirectionalIt first,
                       BidirectionalIt middle,
                       BidirectionalIt last, Compare comp);
  template<class ExecutionPolicy, class BidirectionalIt>
    void inplace_merge(ExecutionPolicy&& exec,
                       BidirectionalIt first,
                       BidirectionalIt middle,
                       BidirectionalIt last);
  template<class ExecutionPolicy, class BidirectionalIt, class Compare>
    void inplace_merge(ExecutionPolicy&& exec,
                       BidirectionalIt first,
                       BidirectionalIt middle,
                       BidirectionalIt last, Compare comp);
 
  namespace ranges {
    template<BidirectionalIterator I, Sentinel<I> S, class Comp = ranges::less,
             class Proj = identity>
      requires Sortable<I, Comp, Proj>
      I inplace_merge(I first, I middle, S last, Comp comp = {}, Proj proj = {});
    template<BidirectionalRange R, class Comp = ranges::less, class Proj = identity>
      requires Sortable<iterator_t<R>, Comp, Proj>
      safe_iterator_t<R>
        inplace_merge(R&& r, iterator_t<R> middle, Comp comp = {},
                      Proj proj = {});
  }
 
  // 集合（set）操作：
  template<class InputIt1, class InputIt2>
    constexpr bool includes(InputIt1 first1, InputIt1 last1,
                            InputIt2 first2, InputIt2 last2);
  template<class InputIt1, class InputIt2, class Compare>
    constexpr bool includes(InputIt1 first1, InputIt1 last1,
                            InputIt2 first2, InputIt2 last2,
                            Compare comp);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    bool includes(ExecutionPolicy&& exec,
                  ForwardIt1 first1, ForwardIt1 last1,
                  ForwardIt2 first2, ForwardIt2 last2);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class Compare>
    bool includes(ExecutionPolicy&& exec,
                  ForwardIt1 first1, ForwardIt1 last1,
                  ForwardIt2 first2, ForwardIt2 last2,
                  Compare comp);
 
  namespace ranges {
    template<InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
             class Proj1 = identity, class Proj2 = identity,
             IndirectStrictWeakOrder<projected<I1, Proj1>, projected<I2, Proj2>> Comp =
               ranges::less>
      constexpr bool includes(I1 first1, S1 last1, I2 first2, S2 last2, Comp comp = {},
                              Proj1 proj1 = {}, Proj2 proj2 = {});
    template<InputRange R1, InputRange R2, class Proj1 = identity,
             class Proj2 = identity,
             IndirectStrictWeakOrder<projected<iterator_t<R1>, Proj1>,
                                     projected<iterator_t<R2>, Proj2>> Comp = ranges::less>
      constexpr bool includes(R1&& r1, R2&& r2, Comp comp = {},
                              Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  template<class InputIt1, class InputIt2, class OutputIt>
    constexpr OutputIt
      set_union(InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2,
                OutputIt result);
  template<class InputIt1, class InputIt2, class OutputIt, class Compare>
    constexpr OutputIt
                set_union(InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2,
                OutputIt result, Compare comp);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class ForwardIt>
    ForwardIt
      set_union(ExecutionPolicy&& exec,
                ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2,
                ForwardIt result);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class ForwardIt, class Compare>
    ForwardIt
      set_union(ExecutionPolicy&& exec,
                ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2, ForwardIt2 last2,
                ForwardIt result, Compare comp);
 
  namespace ranges {
    template<class I1, class I2, class O>
    using set_union_result = binary_transform_result<I1, I2, O>;
 
    template<InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
             WeaklyIncrementable O, class Comp = ranges::less,
             class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<I1, I2, O, Comp, Proj1, Proj2>
      constexpr set_union_result<I1, I2, O>
        set_union(I1 first1, S1 last1, I2 first2, S2 last2, O result, Comp comp = {},
                  Proj1 proj1 = {}, Proj2 proj2 = {});
    template<InputRange R1, InputRange R2, WeaklyIncrementable O,
             class Comp = ranges::less, class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<iterator_t<R1>, iterator_t<R2>, O, Comp, Proj1, Proj2>
      constexpr set_union_result<safe_iterator_t<R1>, safe_iterator_t<R2>, O>
        set_union(R1&& r1, R2&& r2, O result, Comp comp = {},
                  Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  template<class InputIt1, class InputIt2, class OutputIt>
    constexpr OutputIt
      set_intersection(InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2,
                       OutputIt result);
  template<class InputIt1, class InputIt2, class OutputIt, class Compare>
    constexpr OutputIt
      set_intersection(InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2,
                       OutputIt result, Compare comp);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class ForwardIt>
    ForwardIt
      set_intersection(ExecutionPolicy&& exec,
                       ForwardIt1 first1, ForwardIt1 last1,
                       ForwardIt2 first2, ForwardIt2 last2,
                       ForwardIt result);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class ForwardIt, class Compare>
    ForwardIt
      set_intersection(ExecutionPolicy&& exec,
                       ForwardIt1 first1, ForwardIt1 last1,
                       ForwardIt2 first2, ForwardIt2 last2,
                       ForwardIt result, Compare comp);
 
  namespace ranges {
    template<class I1, class I2, class O>
    using set_intersection_result = binary_transform_result<I1, I2, O>;
 
    template<InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
             WeaklyIncrementable O, class Comp = ranges::less,
             class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<I1, I2, O, Comp, Proj1, Proj2>
      constexpr set_intersection_result<I1, I2, O>
        set_intersection(I1 first1, S1 last1, I2 first2, S2 last2, O result,
                         Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {});
    template<InputRange R1, InputRange R2, WeaklyIncrementable O,
             class Comp = ranges::less, class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<iterator_t<R1>, iterator_t<R2>, O, Comp, Proj1, Proj2>
      constexpr set_intersection_result<safe_iterator_t<R1>, safe_iterator_t<R2>, O>
        set_intersection(R1&& r1, R2&& r2, O result,
                         Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  template<class InputIt1, class InputIt2, class OutputIt>
    constexpr OutputIt
      set_difference(InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2,
                     OutputIt result);
  template<class InputIt1, class InputIt2, class OutputIt, class Compare>
    constexpr OutputIt
      set_difference(InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2,
                     OutputIt result, Compare comp);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class ForwardIt>
    ForwardIt
      set_difference(ExecutionPolicy&& exec,
                     ForwardIt1 first1, ForwardIt1 last1,
                     ForwardIt2 first2, ForwardIt2 last2,
                     ForwardIt result);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class ForwardIt, class Compare>
    ForwardIt
      set_difference(ExecutionPolicy&& exec,
                     ForwardIt1 first1, ForwardIt1 last1,
                     ForwardIt2 first2, ForwardIt2 last2,
                     ForwardIt result, Compare comp);
 
  namespace ranges {
    template<class I, class O>
    using set_difference_result = copy_result<I, O>;
 
    template<InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
             WeaklyIncrementable O, class Comp = ranges::less,
             class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<I1, I2, O, Comp, Proj1, Proj2>
      constexpr set_difference_result<I1, O>
        set_difference(I1 first1, S1 last1, I2 first2, S2 last2, O result,
                       Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {});
    template<InputRange R1, InputRange R2, WeaklyIncrementable O,
             class Comp = ranges::less, class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<iterator_t<R1>, iterator_t<R2>, O, Comp, Proj1, Proj2>
      constexpr set_difference_result<safe_iterator_t<R1>, O>
        set_difference(R1&& r1, R2&& r2, O result,
                       Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  template<class InputIt1, class InputIt2, class OutputIt>
    constexpr OutputIt
      set_symmetric_difference(InputIt1 first1, InputIt1 last1,
                               InputIt2 first2, InputIt2 last2,
                               OutputIt result);
  template<class InputIt1, class InputIt2, class OutputIt, class Compare>
    constexpr OutputIt
      set_symmetric_difference(InputIt1 first1, InputIt1 last1,
                               InputIt2 first2, InputIt2 last2,
                               OutputIt result, Compare comp);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class ForwardIt>
    ForwardIt
      set_symmetric_difference(ExecutionPolicy&& exec,
                               ForwardIt1 first1, ForwardIt1 last1,
                               ForwardIt2 first2, ForwardIt2 last2,
                               ForwardIt result);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class ForwardIt, class Compare>
    ForwardIt
      set_symmetric_difference(ExecutionPolicy&& exec,
                               ForwardIt1 first1, ForwardIt1 last1,
                               ForwardIt2 first2, ForwardIt2 last2,
                               ForwardIt result, Compare comp);
 
  namespace ranges {
    template<class I1, class I2, class O>
    using set_symmetric_difference_result = binary_transform_result<I1, I2, O>;
 
    template<InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
             WeaklyIncrementable O, class Comp = ranges::less,
             class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<I1, I2, O, Comp, Proj1, Proj2>
      constexpr set_symmetric_difference_result<I1, I2, O>
        set_symmetric_difference(I1 first1, S1 last1, I2 first2, S2 last2, O result,
                                 Comp comp = {}, Proj1 proj1 = {},
                                 Proj2 proj2 = {});
    template<InputRange R1, InputRange R2, WeaklyIncrementable O,
             class Comp = ranges::less, class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<iterator_t<R1>, iterator_t<R2>, O, Comp, Proj1, Proj2>
      constexpr
        set_symmetric_difference_result<safe_iterator_t<R1>, safe_iterator_t<R2>, O>
        set_symmetric_difference(R1&& r1, R2&& r2, O result, Comp comp = {},
                                 Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  // 堆（heap）操作：
  template<class RandomAccessIt>
    constexpr void push_heap(RandomAccessIt first, RandomAccessIt last);
  template<class RandomAccessIt, class Compare>
    constexpr void push_heap(RandomAccessIt first, RandomAccessIt last, Compare comp);
 
  namespace ranges {
    template<RandomAccessIterator I, Sentinel<I> S, class Comp = ranges::less,
             class Proj = identity>
      requires Sortable<I, Comp, Proj>
      constexpr I
        push_heap(I first, S last, Comp comp = {}, Proj proj = {});
    template<RandomAccessRange R, class Comp = ranges::less, class Proj = identity>
      requires Sortable<iterator_t<R>, Comp, Proj>
      constexpr safe_iterator_t<R>
        push_heap(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  template<class RandomAccessIt>
    constexpr void pop_heap(RandomAccessIt first, RandomAccessIt last);
  template<class RandomAccessIt, class Compare>
    constexpr void pop_heap(RandomAccessIt first, RandomAccessIt last, Compare comp);
 
  namespace ranges {
    template<RandomAccessIterator I, Sentinel<I> S, class Comp = ranges::less,
             class Proj = identity>
      requires Sortable<I, Comp, Proj>
      constexpr I
        pop_heap(I first, S last, Comp comp = {}, Proj proj = {});
    template<RandomAccessRange R, class Comp = ranges::less, class Proj = identity>
      requires Sortable<iterator_t<R>, Comp, Proj>
      constexpr safe_iterator_t<R>
        pop_heap(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  template<class RandomAccessIt>
    constexpr void make_heap(RandomAccessIt first, RandomAccessIt last);
  template<class RandomAccessIt, class Compare>
    constexpr void make_heap(RandomAccessIt first, RandomAccessIt last, Compare comp);
 
  namespace ranges {
    template<RandomAccessIterator I, Sentinel<I> S, class Comp = ranges::less,
             class Proj = identity>
      requires Sortable<I, Comp, Proj>
      constexpr I
        make_heap(I first, S last, Comp comp = {}, Proj proj = {});
    template<RandomAccessRange R, class Comp = ranges::less, class Proj = identity>
      requires Sortable<iterator_t<R>, Comp, Proj>
      constexpr safe_iterator_t<R>
        make_heap(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  template<class RandomAccessIt>
    constexpr void sort_heap(RandomAccessIt first, RandomAccessIt last);
  template<class RandomAccessIt, class Compare>
    constexpr void sort_heap(RandomAccessIt first, RandomAccessIt last, Compare comp);
 
  namespace ranges {
    template<RandomAccessIterator I, Sentinel<I> S, class Comp = ranges::less,
             class Proj = identity>
      requires Sortable<I, Comp, Proj>
      constexpr I
        sort_heap(I first, S last, Comp comp = {}, Proj proj = {});
    template<RandomAccessRange R, class Comp = ranges::less, class Proj = identity>
      requires Sortable<iterator_t<R>, Comp, Proj>
      constexpr safe_iterator_t<R>
        sort_heap(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  template<class RandomAccessIt>
    constexpr bool is_heap(RandomAccessIt first, RandomAccessIt last);
  template<class RandomAccessIt, class Compare>
    constexpr bool is_heap(RandomAccessIt first, RandomAccessIt last, Compare comp);
  template<class ExecutionPolicy, class RandomAccessIt>
    bool is_heap(ExecutionPolicy&& exec,
                 RandomAccessIt first, RandomAccessIt last);
  template<class ExecutionPolicy, class RandomAccessIt, class Compare>
    bool is_heap(ExecutionPolicy&& exec,
                 RandomAccessIt first, RandomAccessIt last, Compare comp);
 
  namespace ranges {
    template<RandomAccessIterator I, Sentinel<I> S, class Proj = identity,
             IndirectStrictWeakOrder<projected<I, Proj>> Comp = ranges::less>
      constexpr bool is_heap(I first, S last, Comp comp = {}, Proj proj = {});
    template<RandomAccessRange R, class Proj = identity,
             IndirectStrictWeakOrder<projected<iterator_t<R>, Proj>> Comp = ranges::less>
      constexpr bool is_heap(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  template<class RandomAccessIt>
    constexpr RandomAccessIt
      is_heap_until(RandomAccessIt first, RandomAccessIt last);
  template<class RandomAccessIt, class Compare>
    constexpr RandomAccessIt
      is_heap_until(RandomAccessIt first, RandomAccessIt last, Compare comp);
  template<class ExecutionPolicy, class RandomAccessIt>
    RandomAccessIt
      is_heap_until(ExecutionPolicy&& exec,
                    RandomAccessIt first, RandomAccessIt last);
  template<class ExecutionPolicy, class RandomAccessIt, class Compare>
    RandomAccessIt
      is_heap_until(ExecutionPolicy&& exec,
                    RandomAccessIt first, RandomAccessIt last, Compare comp);
 
  namespace ranges {
    template<RandomAccessIterator I, Sentinel<I> S, class Proj = identity,
             IndirectStrictWeakOrder<projected<I, Proj>> Comp = ranges::less>
      constexpr I is_heap_until(I first, S last, Comp comp = {}, Proj proj = {});
    template<RandomAccessRange R, class Proj = identity,
             IndirectStrictWeakOrder<projected<iterator_t<R>, Proj>> Comp = ranges::less>
      constexpr safe_iterator_t<R>
        is_heap_until(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  // 最小与最大：
  template<class T> constexpr const T& min(const T& a, const T& b);
  template<class T, class Compare>
    constexpr const T& min(const T& a, const T& b, Compare comp);
  template<class T>
    constexpr T min(initializer_list<T> t);
  template<class T, class Compare>
    constexpr T min(initializer_list<T> t, Compare comp);
 
  namespace ranges {
    template<class T, class Proj = identity,
             IndirectStrictWeakOrder<projected<const T*, Proj>> Comp = ranges::less>
      constexpr const T& min(const T& a, const T& b, Comp comp = {}, Proj proj = {});
    template<Copyable T, class Proj = identity,
             IndirectStrictWeakOrder<projected<const T*, Proj>> Comp = ranges::less>
      constexpr T min(initializer_list<T> r, Comp comp = {}, Proj proj = {});
    template<InputRange R, class Proj = identity,
             IndirectStrictWeakOrder<projected<iterator_t<R>, Proj>> Comp = ranges::less>
      requires IndirectlyCopyableStorable<iterator_t<R>, iter_value_t<iterator_t<R>>*>
      constexpr iter_value_t<iterator_t<R>>
        min(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  template<class T> constexpr const T& max(const T& a, const T& b);
  template<class T, class Compare>
    constexpr const T& max(const T& a, const T& b, Compare comp);
  template<class T>
    constexpr T max(initializer_list<T> t);
  template<class T, class Compare>
    constexpr T max(initializer_list<T> t, Compare comp);
 
  namespace ranges {
    template<class T, class Proj = identity,
             IndirectStrictWeakOrder<projected<const T*, Proj>> Comp = ranges::less>
      constexpr const T& max(const T& a, const T& b, Comp comp = {}, Proj proj = {});
    template<Copyable T, class Proj = identity,
             IndirectStrictWeakOrder<projected<const T*, Proj>> Comp = ranges::less>
      constexpr T max(initializer_list<T> r, Comp comp = {}, Proj proj = {});
    template<InputRange R, class Proj = identity,
             IndirectStrictWeakOrder<projected<iterator_t<R>, Proj>> Comp = ranges::less>
      requires IndirectlyCopyableStorable<iterator_t<R>, iter_value_t<iterator_t<R>>*>
      constexpr iter_value_t<iterator_t<R>>
        max(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  template<class T> constexpr pair<const T&, const T&> minmax(const T& a, const T& b);
  template<class T, class Compare>
    constexpr pair<const T&, const T&> minmax(const T& a, const T& b, Compare comp);
  template<class T>
    constexpr pair<T, T> minmax(initializer_list<T> t);
  template<class T, class Compare>
    constexpr pair<T, T> minmax(initializer_list<T> t, Compare comp);
 
  namespace ranges {
    template<class T>
    struct minmax_result {
      [[no_unique_address]] T min;
      [[no_unique_address]] T max;
 
      template<class T2>
        requires ConvertibleTo<const T&, T2>
        operator minmax_result<T2>() const & {
          return {min, max};
        }
 
      template<class T2>
        requires ConvertibleTo<T, T2>
        operator minmax_result<T2>() && {
          return {std::move(min), std::move(max)};
        }
    };
 
    template<class T, class Proj = identity,
             IndirectStrictWeakOrder<projected<const T*, Proj>> Comp = ranges::less>
      constexpr minmax_result<const T&>
        minmax(const T& a, const T& b, Comp comp = {}, Proj proj = {});
    template<Copyable T, class Proj = identity,
             IndirectStrictWeakOrder<projected<const T*, Proj>> Comp = ranges::less>
      constexpr minmax_result<T>
        minmax(initializer_list<T> r, Comp comp = {}, Proj proj = {});
    template<InputRange R, class Proj = identity,
             IndirectStrictWeakOrder<projected<iterator_t<R>, Proj>> Comp = ranges::less>
      requires IndirectlyCopyableStorable<iterator_t<R>, iter_value_t<iterator_t<R>>*>
      constexpr minmax_result<iter_value_t<iterator_t<R>>>
        minmax(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  template<class ForwardIt>
    constexpr ForwardIt min_element(ForwardIt first, ForwardIt last);
  template<class ForwardIt, class Compare>
    constexpr ForwardIt min_element(ForwardIt first, ForwardIt last,
                                          Compare comp);
  template<class ExecutionPolicy, class ForwardIt>
    ForwardIt min_element(ExecutionPolicy&& exec,
                          ForwardIt first, ForwardIt last);
  template<class ExecutionPolicy, class ForwardIt, class Compare>
    ForwardIt min_element(ExecutionPolicy&& exec,
                          ForwardIt first, ForwardIt last, Compare comp);
 
  namespace ranges {
    template<ForwardIterator I, Sentinel<I> S, class Proj = identity,
             IndirectStrictWeakOrder<projected<I, Proj>> Comp = ranges::less>
      constexpr I min_element(I first, S last, Comp comp = {}, Proj proj = {});
    template<ForwardRange R, class Proj = identity,
             IndirectStrictWeakOrder<projected<iterator_t<R>, Proj>> Comp = ranges::less>
      constexpr safe_iterator_t<R>
        min_element(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  template<class ForwardIt>
    constexpr ForwardIt max_element(ForwardIt first, ForwardIt last);
  template<class ForwardIt, class Compare>
    constexpr ForwardIt max_element(ForwardIt first, ForwardIt last, Compare comp);
  template<class ExecutionPolicy, class ForwardIt>
    ForwardIt max_element(ExecutionPolicy&& exec,
                          ForwardIt first, ForwardIt last);
  template<class ExecutionPolicy, class ForwardIt, class Compare>
    ForwardIt max_element(ExecutionPolicy&& exec,
                          ForwardIt first, ForwardIt last, Compare comp);
 
 namespace ranges {
    template<ForwardIterator I, Sentinel<I> S, class Proj = identity,
             IndirectStrictWeakOrder<projected<I, Proj>> Comp = ranges::less>
      constexpr I max_element(I first, S last, Comp comp = {}, Proj proj = {});
    template<ForwardRange R, class Proj = identity,
             IndirectStrictWeakOrder<projected<iterator_t<R>, Proj>> Comp = ranges::less>
      constexpr safe_iterator_t<R>
        max_element(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  template<class ForwardIt>
    constexpr pair<ForwardIt, ForwardIt>
      minmax_element(ForwardIt first, ForwardIt last);
  template<class ForwardIt, class Compare>
    constexpr pair<ForwardIt, ForwardIt>
      minmax_element(ForwardIt first, ForwardIt last, Compare comp);
  template<class ExecutionPolicy, class ForwardIt>
    pair<ForwardIt, ForwardIt>
      minmax_element(ExecutionPolicy&& exec,
                     ForwardIt first, ForwardIt last);
  template<class ExecutionPolicy, class ForwardIt, class Compare>
    pair<ForwardIt, ForwardIt>
      minmax_element(ExecutionPolicy&& exec,
                     ForwardIt first, ForwardIt last, Compare comp);
 
  namespace ranges {
    template<class I>
    using minmax_element_result = minmax_result<I>;
 
    template<ForwardIterator I, Sentinel<I> S, class Proj = identity,
             IndirectStrictWeakOrder<projected<I, Proj>> Comp = ranges::less>
      constexpr minmax_element_result<I>
        minmax_element(I first, S last, Comp comp = {}, Proj proj = {});
    template<ForwardRange R, class Proj = identity,
             IndirectStrictWeakOrder<projected<iterator_t<R>, Proj>> Comp = ranges::less>
      constexpr minmax_element_result<safe_iterator_t<R>>
        minmax_element(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  // 有界值：
  template<class T>
    constexpr const T& clamp(const T& v, const T& lo, const T& hi);
  template<class T, class Compare>
    constexpr const T& clamp(const T& v, const T& lo, const T& hi, Compare comp);
 
  // 字典序比较：
  template<class InputIt1, class InputIt2>
    constexpr bool
      lexicographical_compare(InputIt1 first1, InputIt1 last1,
                              InputIt2 first2, InputIt2 last2);
  template<class InputIt1, class InputIt2, class Compare>
    constexpr bool
      lexicographical_compare(InputIt1 first1, InputIt1 last1,
                              InputIt2 first2, InputIt2 last2,
                              Compare comp);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    bool
      lexicographical_compare(ExecutionPolicy&& exec,
                              ForwardIt1 first1, ForwardIt1 last1,
                              ForwardIt2 first2, ForwardIt2 last2);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class Compare>
    bool
      lexicographical_compare(ExecutionPolicy&& exec,
                              ForwardIt1 first1, ForwardIt1 last1,
                              ForwardIt2 first2, ForwardIt2 last2,
                              Compare comp);
 
  namespace ranges {
    template<InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
             class Proj1 = identity, class Proj2 = identity,
             IndirectStrictWeakOrder<projected<I1, Proj1>, projected<I2, Proj2>> Comp =
               ranges::less>
      constexpr bool
        lexicographical_compare(I1 first1, S1 last1, I2 first2, S2 last2,
                                Comp comp = {}, Proj1 proj1 = {}, Proj2 proj2 = {});
    template<InputRange R1, InputRange R2, class Proj1 = identity,
             class Proj2 = identity,
             IndirectStrictWeakOrder<projected<iterator_t<R1>, Proj1>,
                                     projected<iterator_t<R2>, Proj2>> Comp = ranges::less>
      constexpr bool
        lexicographical_compare(R1&& r1, R2&& r2, Comp comp = {},
                                Proj1 proj1 = {}, Proj2 proj2 = {});
  }
 
  // 三路比较算法：
  template<class T, class U>
    constexpr auto compare_3way(const T& a, const U& b);
  template<class InputIt1, class InputIt2, class Cmp>
    constexpr auto
      lexicographical_compare_3way(InputIt1 b1, InputIt1 e1, InputIt2 b2, InputIt2 e2,
                                   Cmp comp)
        -> common_comparison_category_t<decltype(comp(*b1, *b2)), strong_ordering>;
  template<class InputIt1, class InputIt2>
    constexpr auto
      lexicographical_compare_3way(InputIt1 b1, InputIt1 e1, InputIt2 b2, InputIt2 e2);
 
  // 排列：
  template<class BidirectionalIt>
    constexpr bool next_permutation(BidirectionalIt first, BidirectionalIt last);
  template<class BidirectionalIt, class Compare>
    constexpr bool next_permutation(BidirectionalIt first, BidirectionalIt last,
                                    Compare comp);
 
  namespace ranges {
    template<BidirectionalIterator I, Sentinel<I> S, class Comp = ranges::less,
             class Proj = identity>
      requires Sortable<I, Comp, Proj>
      constexpr bool
        next_permutation(I first, S last, Comp comp = {}, Proj proj = {});
    template<BidirectionalRange R, class Comp = ranges::less,
             class Proj = identity>
      requires Sortable<iterator_t<R>, Comp, Proj>
      constexpr bool
        next_permutation(R&& r, Comp comp = {}, Proj proj = {});
  }
 
  template<class BidirectionalIt>
    constexpr bool prev_permutation(BidirectionalIt first, BidirectionalIt last);
  template<class BidirectionalIt, class Compare>
    constexpr bool prev_permutation(BidirectionalIt first, BidirectionalIt last,
                                    Compare comp);
 
  namespace ranges {
    template<BidirectionalIterator I, Sentinel<I> S, class Comp = ranges::less,
             class Proj = identity>
      requires Sortable<I, Comp, Proj>
      constexpr bool
        prev_permutation(I first, S last, Comp comp = {}, Proj proj = {});
    template<BidirectionalRange R, class Comp = ranges::less,
             class Proj = identity>
      requires Sortable<iterator_t<R>, Comp, Proj>
      constexpr bool
        prev_permutation(R&& r, Comp comp = {}, Proj proj = {});
  }
}

Jul	AUG	Sep
	21
2018	2019	2020

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标准库头文件 <algorithm>

目录

[编辑] 函数

不修改序列的操作

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（已排序范围上的）二分搜索操作

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[编辑] Niebloid

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（已排序范围上的）集合操作

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