# 实验性库头文件 <experimental/ranges/algorithm>

< cpp‎ | header‎ | experimental

此头文件是范围库的一部分。

### 标签说明符

定义于命名空间 `std::experimental::ranges::tag`
in in1 in2 out out1 out2 fun min max begin end | 用于 ranges::tagged 的标签说明符 (类)

### 不修改序列的操作

定义于命名空间 `std::experimental::ranges`
all_of any_of none_of | 检查谓词是否对范围中所有、任一或无元素为 true (函数模板)
for_each | 应用函数到元素范围 (函数模板)
count count_if | 返回满足特定判别标准的元素数 (函数模板)
mismatch | 寻找两个范围出现不同的首个位置 (函数模板)
equal | 确定元素的二个集合是否相同 (函数模板)
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)
find find_if find_if_not | 寻找首个满足特定判别标准的元素 (函数模板)
find_end | 在特定范围中寻找最后出现的元素序列 (函数模板)
find_first_of | 搜索元素集中的任何元素 (函数模板)
adjacent_find | 寻找头两个相等（或满足给定谓词）的相邻项 (函数模板)
search | 搜索一个元素范围 (函数模板)
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)

### 修改序列的操作

定义于命名空间 `std::experimental::ranges`
copy copy_if | 将某一范围的元素复制到一个新的位置 (函数模板)
copy_n | 将一定数目的元素复制到一个新的位置 (函数模板)
copy_backward | 按从后往前的顺序复制一个范围内的元素 (函数模板)
move | 将某一范围的元素移动到一个新的位置 (函数模板)
move_backward | 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)
fill | 将一个特定值赋值给一个元素范围 (函数模板)
fill_n | 将一个值赋值给一定数量的元素 (函数模板)
transform | 应用一个函数到元素范围 (函数模板)
generate | 保存函数结果于一个范围中 (函数模板)
generate_n | 保存 N 次应用一个函数的结果 (函数模板)
remove remove_if | 移除满足特定判别标准的元素 (函数模板)
remove_copy remove_copy_if | 复制元素范围，忽略满足特定判别标准的元素 (函数模板)
replace replace_if | 将所有满足特定判别标准的值替换为另一值 (函数模板)
replace_copy replace_copy_if | 复制范围，以另一值替换满足特定判别标准的元素 (函数模板)
swap_ranges | 交换两个元素范围 (函数模板)
reverse | 逆转范围中的元素顺序 (函数模板)
reverse_copy | 创建一个范围的逆向副本 (函数模板)
rotate | 旋转范围中的元素顺序 (函数模板)
rotate_copy | 复制并旋转元素范围 (函数模板)
shuffle | 随机重排范围中的元素 (函数模板)
unique | 移除范围中连续的重复元素 (函数模板)
unique_copy | 创建某范围的不含连续重复元素的副本 (函数模板)

### 划分操作

定义于命名空间 `std::experimental::ranges`
is_partitioned | 判断范围是否已按给定的谓词划分 (函数模板)
partition | 将范围中的元素分为两组 (函数模板)
partition_copy | 复制一个范围，将各元素分为两组 (函数模板)
stable_partition | 划分元素到两个组中，同时保持其相对顺序 (函数模板)
partition_point | 定位已划分范围的划分点 (函数模板)

### 排序操作

定义于命名空间 `std::experimental::ranges`
is_sorted | 检查范围是否以升序排序 (函数模板)
is_sorted_until | 寻找最大已排序子范围 (函数模板)
sort | 将范围按升序排序 (函数模板)
partial_sort | 排序一个范围的前 N 个元素 (函数模板)
partial_sort_copy | 对范围内的元素进行复制并部分排序 (函数模板)
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)
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)

### （已排序范围上的）二分搜索操作

定义于命名空间 `std::experimental::ranges`
lower_bound | 返回指向首个不小于给定值的元素的迭代器 (函数模板)
upper_bound | 返回指向首个大于固定值的元素的迭代器 (函数模板)
binary_search | 确定元素是否存在于固定范围中 (函数模板)
equal_range | 返回匹配特定关键的元素范围 (函数模板)

### （已排序范围上的）集合操作

定义于命名空间 `std::experimental::ranges`
merge | 归并两个已排序范围 (函数模板)
inplace_merge | 就地归并两个已排序范围 (函数模板)
includes | 若一个集合是另一个的子集则返回 true (函数模板)
set_difference | 计算两个集合的差集 (函数模板)
set_intersection | 计算两个集合的交集 (函数模板)
set_symmetric_difference | 计算两个集合的对称差 (函数模板)
set_union | 计算两个集合的并集 (函数模板)

### 堆操作

定义于命名空间 `std::experimental::ranges`
is_heap | 检查给定范围是否为一个最大堆 (函数模板)
is_heap_until | 寻找作为最大堆的最大子范围 (函数模板)
make_heap | 从元素范围中创建出最大堆 (函数模板)
push_heap | 添加元素到最大堆 (函数模板)
pop_heap | 从最大堆移除最大元素 (函数模板)
sort_heap | 将最大堆转化成以升序排序的元素范围 (函数模板)

### 最小/最大操作

定义于命名空间 `std::experimental::ranges`
max | 返回给定值的较大者 (函数模板)
max_element | 返回范围中的最大元素 (函数模板)
min | 返回给定值的较小者 (函数模板)
min_element | 返回范围中的最小元素 (函数模板)
minmax | 返回二个元素的较小和较大者 (函数模板)
minmax_element | 返回范围中的最小和最大元素 (函数模板)

### 排列操作

定义于命名空间 `std::experimental::ranges`
is_permutation | 判断一个序列是否为另一个序列的排列 (函数模板)
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)
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)

### 概要

    #include <initializer_list>

    namespace std { namespace experimental { namespace ranges { inline namespace v1 {

    namespace tag {
      struct in;
      struct in1;
      struct in2;
      struct out;
      struct out1;
      struct out2;
      struct fun;
      struct min;
      struct max;
      struct begin;
      struct end;
    }

    template <InputIterator I, Sentinel<I> S, class Proj = identity,
        IndirectUnaryPredicate<projected<I, Proj>> Pred>
      bool all_of(I first, S last, Pred pred, Proj proj = Proj{});

    template <InputRange Rng, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      bool all_of(Rng&& rng, Pred pred, Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, class Proj = identity,
        IndirectUnaryPredicate<projected<I, Proj>> Pred>
      bool any_of(I first, S last, Pred pred, Proj proj = Proj{});

    template <InputRange Rng, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      bool any_of(Rng&& rng, Pred pred, Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, class Proj = identity,
        IndirectUnaryPredicate<projected<I, Proj>> Pred>
      bool none_of(I first, S last, Pred pred, Proj proj = Proj{});

    template <InputRange Rng, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      bool none_of(Rng&& rng, Pred pred, Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, class Proj = identity,
        IndirectUnaryInvocable<projected<I, Proj>> Fun>
      tagged_pair<tag::in(I), tag::fun(Fun)>
        for_each(I first, S last, Fun f, Proj proj = Proj{});

    template <InputRange Rng, class Proj = identity,
        IndirectUnaryInvocable<projected<iterator_t<Rng>, Proj>> Fun>
      tagged_pair<tag::in(safe_iterator_t<Rng>), tag::fun(Fun)>
        for_each(Rng&& rng, Fun f, Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, class T, class Proj = identity>
      requires IndirectRelation<equal_to<>, projected<I, Proj>, const T*>
      I find(I first, S last, const T& value, Proj proj = Proj{});

    template <InputRange Rng, class T, class Proj = identity>
      requires IndirectRelation<equal_to<>, projected<iterator_t<Rng>, Proj>, const T*>
      safe_iterator_t<Rng>
        find(Rng&& rng, const T& value, Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, class Proj = identity,
        IndirectUnaryPredicate<projected<I, Proj>> Pred>
      I find_if(I first, S last, Pred pred, Proj proj = Proj{});

    template <InputRange Rng, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      safe_iterator_t<Rng>
        find_if(Rng&& rng, Pred pred, Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, class Proj = identity,
        IndirectUnaryPredicate<projected<I, Proj>> Pred>
      I find_if_not(I first, S last, Pred pred, Proj proj = Proj{});

    template <InputRange Rng, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      safe_iterator_t<Rng>
        find_if_not(Rng&& rng, Pred pred, Proj proj = Proj{});

    template <ForwardIterator I1, Sentinel<I1> S1, ForwardIterator I2,
        Sentinel<I2> S2, class Proj = identity,
        IndirectRelation<I2, projected<I1, Proj>> Pred = equal_to<>>
      I1
        find_end(I1 first1, S1 last1, I2 first2, S2 last2,
                 Pred pred = Pred{}, Proj proj = Proj{});

    template <ForwardRange Rng1, ForwardRange Rng2, class Proj = identity,
        IndirectRelation<iterator_t<Rng2>,
          projected<iterator_t<Rng>, Proj>> Pred = equal_to<>>
      safe_iterator_t<Rng1>
        find_end(Rng1&& rng1, Rng2&& rng2, Pred pred = Pred{}, Proj proj = Proj{});

    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 = equal_to<>>
      I1
        find_first_of(I1 first1, S1 last1, I2 first2, S2 last2,
                      Pred pred = Pred{},
                      Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputRange Rng1, ForwardRange Rng2, class Proj1 = identity,
        class Proj2 = identity,
        IndirectRelation<projected<iterator_t<Rng1>, Proj1>,
          projected<iterator_t<Rng2>, Proj2>> Pred = equal_to<>>
      safe_iterator_t<Rng1>
        find_first_of(Rng1&& rng1, Rng2&& rng2,
                      Pred pred = Pred{},
                      Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <ForwardIterator I, Sentinel<I> S, class Proj = identity,
        IndirectRelation<projected<I, Proj>> Pred = equal_to<>>
      I
        adjacent_find(I first, S last, Pred pred = Pred{},
                      Proj proj = Proj{});

    template <ForwardRange Rng, class Proj = identity,
        IndirectRelation<projected<iterator_t<Rng>, Proj>> Pred = equal_to<>>
      safe_iterator_t<Rng>
        adjacent_find(Rng&& rng, Pred pred = Pred{}, Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, class T, class Proj = identity>
      requires IndirectRelation<equal_to<>, projected<I, Proj>, const T*>
      difference_type_t<I>
        count(I first, S last, const T& value, Proj proj = Proj{});

    template <InputRange Rng, class T, class Proj = identity>
      requires IndirectRelation<equal_to<>, projected<iterator_t<Rng>, Proj>, const T*>
      difference_type_t<iterator_t<Rng>>
        count(Rng&& rng, const T& value, Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, class Proj = identity,
        IndirectUnaryPredicate<projected<I, Proj>> Pred>
      difference_type_t<I>
        count_if(I first, S last, Pred pred, Proj proj = Proj{});

    template <InputRange Rng, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      difference_type_t<iterator_t<Rng>>
        count_if(Rng&& rng, Pred pred, Proj proj = Proj{});

    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 = equal_to<>>
      tagged_pair<tag::in1(I1), tag::in2(I2)>
        mismatch(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = Pred{},
                 Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputRange Rng1, InputRange Rng2,
        class Proj1 = identity, class Proj2 = identity,
        IndirectRelation<projected<iterator_t<Rng1>, Proj1>,
          projected<iterator_t<Rng2>, Proj2>> Pred = equal_to<>>
      tagged_pair<tag::in1(safe_iterator_t<Rng1>),
                  tag::in2(safe_iterator_t<Rng2>)>
        mismatch(Rng1&& rng1, Rng2&& rng2, Pred pred = Pred{},
                 Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
        class Pred = equal_to<>, class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyComparable<I1, I2, Pred, Proj1, Proj2>
      bool equal(I1 first1, S1 last1, I2 first2, S2 last2,
                 Pred pred = Pred{},
                 Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputRange Rng1, InputRange Rng2, class Pred = equal_to<>,
        class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyComparable<iterator_t<Rng1>, iterator_t<Rng2>, Pred, Proj1, Proj2>
      bool equal(Rng1&& rng1, Rng2&& rng2, Pred pred = Pred{},
                 Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <ForwardIterator I1, Sentinel<I1> S1, ForwardIterator I2,
        Sentinel<I2> S2, class Pred = equal_to<>, class Proj1 = identity,
        class Proj2 = identity>
      requires IndirectlyComparable<I1, I2, Pred, Proj1, Proj2>
      bool is_permutation(I1 first1, S1 last1, I2 first2, S2 last2,
                          Pred pred = Pred{},
                          Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <ForwardRange Rng1, ForwardRange Rng2, class Pred = equal_to<>,
        class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyComparable<iterator_t<Rng1>, iterator_t<Rng2>, Pred, Proj1, Proj2>
      bool is_permutation(Rng1&& rng1, Rng2&& rng2, Pred pred = Pred{},
                          Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <ForwardIterator I1, Sentinel<I1> S1, ForwardIterator I2,
        Sentinel<I2> S2, class Pred = equal_to<>,
        class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyComparable<I1, I2, Pred, Proj1, Proj2>
      I1
        search(I1 first1, S1 last1, I2 first2, S2 last2,
               Pred pred = Pred{},
               Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <ForwardRange Rng1, ForwardRange Rng2, class Pred = equal_to<>,
        class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyComparable<iterator_t<Rng1>, iterator_t<Rng2>, Pred, Proj1, Proj2>
      safe_iterator_t<Rng1>
        search(Rng1&& rng1, Rng2&& rng2, Pred pred = Pred{},
               Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <ForwardIterator I, Sentinel<I> S, class T,
        class Pred = equal_to<>, class Proj = identity>
      requires IndirectlyComparable<I, const T*, Pred, Proj>
      I
        search_n(I first, S last, difference_type_t<I> count,
                 const T& value, Pred pred = Pred{},
                 Proj proj = Proj{});

    template <ForwardRange Rng, class T, class Pred = equal_to<>,
        class Proj = identity>
      requires IndirectlyComparable<iterator_t<Rng>, const T*, Pred, Proj>
      safe_iterator_t<Rng>
        search_n(Rng&& rng, difference_type_t<iterator_t<Rng>> count,
                 const T& value, Pred pred = Pred{}, Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, WeaklyIncrementable O>
      requires IndirectlyCopyable<I, O>
      tagged_pair<tag::in(I), tag::out(O)>
        copy(I first, S last, O result);

    template <InputRange Rng, WeaklyIncrementable O>
      requires IndirectlyCopyable<iterator_t<Rng>, O>
      tagged_pair<tag::in(safe_iterator_t<Rng>), tag::out(O)>
        copy(Rng&& rng, O result);

    template <InputIterator I, WeaklyIncrementable O>
      requires IndirectlyCopyable<I, O>
      tagged_pair<tag::in(I), tag::out(O)>
        copy_n(I first, difference_type_t<I> n, O result);

    template <InputIterator I, Sentinel<I> S, WeaklyIncrementable O, class Proj = identity,
        IndirectUnaryPredicate<projected<I, Proj>> Pred>
      requires IndirectlyCopyable<I, O>
      tagged_pair<tag::in(I), tag::out(O)>
        copy_if(I first, S last, O result, Pred pred, Proj proj = Proj{});

    template <InputRange Rng, WeaklyIncrementable O, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      requires IndirectlyCopyable<iterator_t<Rng>, O>
      tagged_pair<tag::in(safe_iterator_t<Rng>), tag::out(O)>
        copy_if(Rng&& rng, O result, Pred pred, Proj proj = Proj{});

    template <BidirectionalIterator I1, Sentinel<I1> S1, BidirectionalIterator I2>
      requires IndirectlyCopyable<I1, I2>
      tagged_pair<tag::in(I1), tag::out(I2)>
        copy_backward(I1 first, S1 last, I2 result);

    template <BidirectionalRange Rng, BidirectionalIterator I>
      requires IndirectlyCopyable<iterator_t<Rng>, I>
      tagged_pair<tag::in(safe_iterator_t<Rng>), tag::out(I)>
        copy_backward(Rng&& rng, I result);

    template <InputIterator I, Sentinel<I> S, WeaklyIncrementable O>
      requires IndirectlyMovable<I, O>
      tagged_pair<tag::in(I), tag::out(O)>
        move(I first, S last, O result);

    template <InputRange Rng, WeaklyIncrementable O>
      requires IndirectlyMovable<iterator_t<Rng>, O>
      tagged_pair<tag::in(safe_iterator_t<Rng>), tag::out(O)>
        move(Rng&& rng, O result);

    template <BidirectionalIterator I1, Sentinel<I1> S1, BidirectionalIterator I2>
      requires IndirectlyMovable<I1, I2>
      tagged_pair<tag::in(I1), tag::out(I2)>
        move_backward(I1 first, S1 last, I2 result);

    template <BidirectionalRange Rng, BidirectionalIterator I>
      requires IndirectlyMovable<iterator_t<Rng>, I>
      tagged_pair<tag::in(safe_iterator_t<Rng>), tag::out(I)>
        move_backward(Rng&& rng, I result);

    template <ForwardIterator I1, Sentinel<I1> S1, ForwardIterator I2, Sentinel<I2> S2>
      requires IndirectlySwappable<I1, I2>
      tagged_pair<tag::in1(I1), tag::in2(I2)>
        swap_ranges(I1 first1, S1 last1, I2 first2, S2 last2);

    template <ForwardRange Rng1, ForwardRange Rng2>
      requires IndirectlySwappable<iterator_t<Rng1>, iterator_t<Rng2>>
      tagged_pair<tag::in1(safe_iterator_t<Rng1>), tag::in2(safe_iterator_t<Rng2>)>
        swap_ranges(Rng1&& rng1, Rng2&& rng2);

    template <InputIterator I, Sentinel<I> S, WeaklyIncrementable O,
        CopyConstructible F, class Proj = identity>
      requires Writable<O, indirect_result_of_t<F&(projected<I, Proj>)>>
      tagged_pair<tag::in(I), tag::out(O)>
        transform(I first, S last, O result, F op, Proj proj = Proj{});

    template <InputRange Rng, WeaklyIncrementable O, CopyConstructible F,
        class Proj = identity>
      requires Writable<O, indirect_result_of_t<F&(
        projected<iterator_t<R>, Proj>)>>
      tagged_pair<tag::in(safe_iterator_t<Rng>), tag::out(O)>
        transform(Rng&& rng, O result, F op, Proj proj = Proj{});

    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_of_t<F&(projected<I1, Proj1>,
        projected<I2, Proj2>)>>
      tagged_tuple<tag::in1(I1), tag::in2(I2), tag::out(O)>
        transform(I1 first1, S1 last1, I2 first2, S2 last2, O result,
                  F binary_op, Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputRange Rng1, InputRange Rng2, WeaklyIncrementable O,
        CopyConstructible F, class Proj1 = identity, class Proj2 = identity>
      requires Writable<O, indirect_result_of_t<F&(
        projected<iterator_t<Rng1>, Proj1>, projected<iterator_t<Rng2>, Proj2>)>>
      tagged_tuple<tag::in1(safe_iterator_t<Rng1>),
                   tag::in2(safe_iterator_t<Rng2>),
                   tag::out(O)>
        transform(Rng1&& rng1, Rng2&& rng2, O result,
                  F binary_op, Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputIterator I, Sentinel<I> S, class T1, class T2, class Proj = identity>
      requires Writable<I, const T2&> &&
        IndirectRelation<equal_to<>, projected<I, Proj>, const T1*>
      I
        replace(I first, S last, const T1& old_value, const T2& new_value, Proj proj = Proj{});

    template <InputRange Rng, class T1, class T2, class Proj = identity>
      requires Writable<iterator_t<Rng>, const T2&> &&
        IndirectRelation<equal_to<>, projected<iterator_t<Rng>, Proj>, const T1*>
      safe_iterator_t<Rng>
        replace(Rng&& rng, const T1& old_value, const T2& new_value, Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, class T, class Proj = identity,
        IndirectUnaryPredicate<projected<I, Proj>> Pred>
      requires Writable<I, const T&>
      I
        replace_if(I first, S last, Pred pred, const T& new_value, Proj proj = Proj{});

    template <InputRange Rng, class T, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      requires Writable<iterator_t<Rng>, const T&>
      safe_iterator_t<Rng>
        replace_if(Rng&& rng, Pred pred, const T& new_value, Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, class T1, class T2, OutputIterator<const T2&> O,
        class Proj = identity>
      requires IndirectlyCopyable<I, O> &&
        IndirectRelation<equal_to<>, projected<I, Proj>, const T1*>
      tagged_pair<tag::in(I), tag::out(O)>
        replace_copy(I first, S last, O result, const T1& old_value, const T2& new_value,
                     Proj proj = Proj{});

    template <InputRange Rng, class T1, class T2, OutputIterator<const T2&> O,
        class Proj = identity>
      requires IndirectlyCopyable<iterator_t<Rng>, O> &&
        IndirectRelation<equal_to<>, projected<iterator_t<Rng>, Proj>, const T1*>
      tagged_pair<tag::in(safe_iterator_t<Rng>), tag::out(O)>
        replace_copy(Rng&& rng, O result, const T1& old_value, const T2& new_value,
                     Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, class T, OutputIterator<const T&> O,
        class Proj = identity, IndirectUnaryPredicate<projected<I, Proj>> Pred>
      requires IndirectlyCopyable<I, O>
      tagged_pair<tag::in(I), tag::out(O)>
        replace_copy_if(I first, S last, O result, Pred pred, const T& new_value,
                        Proj proj = Proj{});

    template <InputRange Rng, class T, OutputIterator<const T&> O, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      requires IndirectlyCopyable<iterator_t<Rng>, O>
      tagged_pair<tag::in(safe_iterator_t<Rng>), tag::out(O)>
        replace_copy_if(Rng&& rng, O result, Pred pred, const T& new_value,
                        Proj proj = Proj{});

    template <class T, OutputIterator<const T&> O, Sentinel<O> S>
      O fill(O first, S last, const T& value);

    template <class T, OutputRange<const T&> Rng>
      safe_iterator_t<Rng>
        fill(Rng&& rng, const T& value);

    template <class T, OutputIterator<const T&> O>
      O fill_n(O first, difference_type_t<O> n, const T& value);

    template <Iterator O, Sentinel<O> S, CopyConstructible F>
      requires Invocable<F&> && Writable<O, result_of_t<F&()>>
      O generate(O first, S last, F gen);

    template <class Rng, CopyConstructible F>
      requires Invocable<F&> && OutputRange<Rng, result_of_t<F&()>>
      safe_iterator_t<Rng>
        generate(Rng&& rng, F gen);

    template <Iterator O, CopyConstructible F>
      requires Invocable<F&> && Writable<O, result_of_t<F&()>>
      O generate_n(O first, difference_type_t<O> n, F gen);

    template <ForwardIterator I, Sentinel<I> S, class T, class Proj = identity>
      requires Permutable<I> &&
        IndirectRelation<equal_to<>, projected<I, Proj>, const T*>
      I remove(I first, S last, const T& value, Proj proj = Proj{});

    template <ForwardRange Rng, class T, class Proj = identity>
      requires Permutable<iterator_t<Rng>> &&
        IndirectRelation<equal_to<>, projected<iterator_t<Rng>, Proj>, const T*>
      safe_iterator_t<Rng>
        remove(Rng&& rng, const T& value, Proj proj = Proj{});

    template <ForwardIterator I, Sentinel<I> S, class Proj = identity,
        IndirectUnaryPredicate<projected<I, Proj>> Pred>
      requires Permutable<I>
        I remove_if(I first, S last, Pred pred, Proj proj = Proj{});

    template <ForwardRange Rng, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      requires Permutable<iterator_t<Rng>>
      safe_iterator_t<Rng>
        remove_if(Rng&& rng, Pred pred, Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, WeaklyIncrementable O, class T,
        class Proj = identity>
      requires IndirectlyCopyable<I, O> &&
        IndirectRelation<equal_to<>, projected<I, Proj>, const T*>
      tagged_pair<tag::in(I), tag::out(O)>
        remove_copy(I first, S last, O result, const T& value, Proj proj = Proj{});

    template <InputRange Rng, WeaklyIncrementable O, class T, class Proj = identity>
      requires IndirectlyCopyable<iterator_t<Rng>, O> &&
        IndirectRelation<equal_to<>, projected<iterator_t<Rng>, Proj>, const T*>
      tagged_pair<tag::in(safe_iterator_t<Rng>), tag::out(O)>
        remove_copy(Rng&& rng, O result, const T& value, Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, WeaklyIncrementable O,
        class Proj = identity, IndirectUnaryPredicate<projected<I, Proj>> Pred>
      requires IndirectlyCopyable<I, O>
      tagged_pair<tag::in(I), tag::out(O)>
        remove_copy_if(I first, S last, O result, Pred pred, Proj proj = Proj{});

    template <InputRange Rng, WeaklyIncrementable O, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      requires IndirectlyCopyable<iterator_t<Rng>, O>
      tagged_pair<tag::in(safe_iterator_t<Rng>), tag::out(O)>
        remove_copy_if(Rng&& rng, O result, Pred pred, Proj proj = Proj{});

    template <ForwardIterator I, Sentinel<I> S, class Proj = identity,
        IndirectRelation<projected<I, Proj>> R = equal_to<>>
      requires Permutable<I>
      I unique(I first, S last, R comp = R{}, Proj proj = Proj{});

    template <ForwardRange Rng, class Proj = identity,
        IndirectRelation<projected<iterator_t<Rng>, Proj>> R = equal_to<>>
      requires Permutable<iterator_t<Rng>>
      safe_iterator_t<Rng>
        unique(Rng&& rng, R comp = R{}, Proj proj = Proj{});

    template <InputIterator I, Sentinel<I> S, WeaklyIncrementable O,
        class Proj = identity, IndirectRelation<projected<I, Proj>> R = equal_to<>>
      requires IndirectlyCopyable<I, O> &&
        (ForwardIterator<I> ||
        (InputIterator<O> && Same<value_type_t<I>, value_type_t<O>>) ||
        IndirectlyCopyableStorable<I, O>)
      tagged_pair<tag::in(I), tag::out(O)>
        unique_copy(I first, S last, O result, R comp = R{}, Proj proj = Proj{});

    template <InputRange Rng, WeaklyIncrementable O, class Proj = identity,
        IndirectRelation<projected<iterator_t<Rng>, Proj>> R = equal_to<>>
      requires IndirectlyCopyable<iterator_t<Rng>, O> &&
        (ForwardIterator<iterator_t<Rng>> ||
        (InputIterator<O> && Same<value_type_t<iterator_t<Rng>>, value_type_t<O>>) ||
        IndirectlyCopyableStorable<iterator_t<Rng>, O>)
      tagged_pair<tag::in(safe_iterator_t<Rng>), tag::out(O)>
        unique_copy(Rng&& rng, O result, R comp = R{}, Proj proj = Proj{});

    template <BidirectionalIterator I, Sentinel<I> S>
      requires Permutable<I>
      I reverse(I first, S last);

    template <BidirectionalRange Rng>
      requires Permutable<iterator_t<Rng>>
      safe_iterator_t<Rng>
        reverse(Rng&& rng);

    template <BidirectionalIterator I, Sentinel<I> S, WeaklyIncrementable O>
      requires IndirectlyCopyable<I, O>
      tagged_pair<tag::in(I), tag::out(O)> reverse_copy(I first, S last, O result);

    template <BidirectionalRange Rng, WeaklyIncrementable O>
      requires IndirectlyCopyable<iterator_t<Rng>, O>
      tagged_pair<tag::in(safe_iterator_t<Rng>), tag::out(O)>
        reverse_copy(Rng&& rng, O result);

    template <ForwardIterator I, Sentinel<I> S>
      requires Permutable<I>
      tagged_pair<tag::begin(I), tag::end(I)>
        rotate(I first, I middle, S last);

    template <ForwardRange Rng>
      requires Permutable<iterator_t<Rng>>
      tagged_pair<tag::begin(safe_iterator_t<Rng>),
                  tag::end(safe_iterator_t<Rng>)>
        rotate(Rng&& rng, iterator_t<Rng> middle);

    template <ForwardIterator I, Sentinel<I> S, WeaklyIncrementable O>
      requires IndirectlyCopyable<I, O>
      tagged_pair<tag::in(I), tag::out(O)>
        rotate_copy(I first, I middle, S last, O result);

    template <ForwardRange Rng, WeaklyIncrementable O>
      requires IndirectlyCopyable<iterator_t<Rng>, O>
      tagged_pair<tag::in(safe_iterator_t<Rng>), tag::out(O)>
        rotate_copy(Rng&& rng, iterator_t<Rng> middle, O result);

    template <RandomAccessIterator I, Sentinel<I> S, class Gen>
      requires Permutable<I> &&
        UniformRandomNumberGenerator<remove_reference_t<Gen>> &&
        ConvertibleTo<result_of_t<Gen&()>, difference_type_t<I>>
      I shuffle(I first, S last, Gen&& g);

    template <RandomAccessRange Rng, class Gen>
      requires Permutable<I> &&
        UniformRandomNumberGenerator<remove_reference_t<Gen>> &&
        ConvertibleTo<result_of_t<Gen&()>, difference_type_t<I>>
      safe_iterator_t<Rng>
        shuffle(Rng&& rng, Gen&& g);

    template <InputIterator I, Sentinel<I> S, class Proj = identity,
        IndirectUnaryPredicate<projected<I, Proj>> Pred>
      bool is_partitioned(I first, S last, Pred pred, Proj proj = Proj{});

    template <InputRange Rng, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      bool
        is_partitioned(Rng&& rng, Pred pred, Proj proj = Proj{});

    template <ForwardIterator I, Sentinel<I> S, class Proj = identity,
        IndirectUnaryPredicate<projected<I, Proj>> Pred>
      requires Permutable<I>
        I partition(I first, S last, Pred pred, Proj proj = Proj{});

    template <ForwardRange Rng, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      requires Permutable<iterator_t<Rng>>
      safe_iterator_t<Rng>
        partition(Rng&& rng, Pred pred, Proj proj = Proj{});

    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 = Proj{});

    template <BidirectionalRange Rng, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      requires Permutable<iterator_t<Rng>>
      safe_iterator_t<Rng>
        stable_partition(Rng&& rng, Pred pred, Proj proj = Proj{});

    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>
      tagged_tuple<tag::in(I), tag::out1(O1), tag::out2(O2)>
        partition_copy(I first, S last, O1 out_true, O2 out_false, Pred pred,
                       Proj proj = Proj{});

    template <InputRange Rng, WeaklyIncrementable O1, WeaklyIncrementable O2,
        class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      requires IndirectlyCopyable<iterator_t<Rng>, O1> &&
        IndirectlyCopyable<iterator_t<Rng>, O2>
      tagged_tuple<tag::in(safe_iterator_t<Rng>), tag::out1(O1), tag::out2(O2)>
        partition_copy(Rng&& rng, O1 out_true, O2 out_false, Pred pred, Proj proj = Proj{});

    template <ForwardIterator I, Sentinel<I> S, class Proj = identity,
        IndirectUnaryPredicate<projected<I, Proj>> Pred>
      I partition_point(I first, S last, Pred pred, Proj proj = Proj{});

    template <ForwardRange Rng, class Proj = identity,
        IndirectUnaryPredicate<projected<iterator_t<Rng>, Proj>> Pred>
      safe_iterator_t<Rng>
        partition_point(Rng&& rng, Pred pred, Proj proj = Proj{});

    template <RandomAccessIterator I, Sentinel<I> S, class Comp = less<>,
        class Proj = identity>
      requires Sortable<I, Comp, Proj>
        I sort(I first, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessRange Rng, class Comp = less<>, class Proj = identity>
      requires Sortable<iterator_t<Rng>, Comp, Proj>
      safe_iterator_t<Rng>
        sort(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessIterator I, Sentinel<I> S, class Comp = less<>,
        class Proj = identity>
      requires Sortable<I, Comp, Proj>
        I stable_sort(I first, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessRange Rng, class Comp = less<>, class Proj = identity>
      requires Sortable<iterator_t<Rng>, Comp, Proj>
      safe_iterator_t<Rng>
        stable_sort(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessIterator I, Sentinel<I> S, class Comp = less<>,
        class Proj = identity>
      requires Sortable<I, Comp, Proj>
        I partial_sort(I first, I middle, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessRange Rng, class Comp = less<>, class Proj = identity>
      requires Sortable<iterator_t<Rng>, Comp, Proj>
      safe_iterator_t<Rng>
        partial_sort(Rng&& rng, iterator_t<Rng> middle, Comp comp = Comp{},
                     Proj proj = Proj{});

    template <InputIterator I1, Sentinel<I1> S1, RandomAccessIterator I2, Sentinel<I2> S2,
        class Comp = less<>, class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyCopyable<I1, I2> && Sortable<I2, Comp, Proj2> &&
        IndirectStrictWeakOrder<Comp, projected<I1, Proj1>, projected<I2, Proj2>>
      I2
        partial_sort_copy(I1 first, S1 last, I2 result_first, S2 result_last,
                          Comp comp = Comp{}, Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputRange Rng1, RandomAccessRange Rng2, class Comp = less<>,
        class Proj1 = identity, class Proj2 = identity>
      requires IndirectlyCopyable<iterator_t<Rng1>, iterator_t<Rng2>> &&
        Sortable<iterator_t<Rng2>, Comp, Proj2> &&
        IndirectStrictWeakOrder<Comp, projected<iterator_t<Rng1>, Proj1>,
          projected<iterator_t<Rng2>, Proj2>>
      safe_iterator_t<Rng2>
        partial_sort_copy(Rng1&& rng, Rng2&& result_rng, Comp comp = Comp{},
                          Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <ForwardIterator I, Sentinel<I> S, class Proj = identity,
        IndirectStrictWeakOrder<projected<I, Proj>> Comp = less<>>
      bool is_sorted(I first, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardRange Rng, class Proj = identity,
        IndirectStrictWeakOrder<projected<iterator_t<Rng>, Proj>> Comp = less<>>
      bool
        is_sorted(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardIterator I, Sentinel<I> S, class Proj = identity,
        IndirectStrictWeakOrder<projected<I, Proj>> Comp = less<>>
      I is_sorted_until(I first, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardRange Rng, class Proj = identity,
        IndirectStrictWeakOrder<projected<iterator_t<Rng>, Proj>> Comp = less<>>
      safe_iterator_t<Rng>
        is_sorted_until(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessIterator I, Sentinel<I> S, class Comp = less<>,
        class Proj = identity>
      requires Sortable<I, Comp, Proj>
        I nth_element(I first, I nth, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessRange Rng, class Comp = less<>, class Proj = identity>
      requires Sortable<iterator_t<Rng>, Comp, Proj>
      safe_iterator_t<Rng>
        nth_element(Rng&& rng, iterator_t<Rng> nth, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardIterator I, Sentinel<I> S, class T, class Proj = identity,
        IndirectStrictWeakOrder<const T*, projected<I, Proj>> Comp = less<>>
      I
        lower_bound(I first, S last, const T& value, Comp comp = Comp{},
                    Proj proj = Proj{});

    template <ForwardRange Rng, class T, class Proj = identity,
        IndirectStrictWeakOrder<const T*, projected<iterator_t<Rng>, Proj>> Comp = less<>>
      safe_iterator_t<Rng>
        lower_bound(Rng&& rng, const T& value, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardIterator I, Sentinel<I> S, class T, class Proj = identity,
        IndirectStrictWeakOrder<const T*, projected<I, Proj>> Comp = less<>>
      I
        upper_bound(I first, S last, const T& value, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardRange Rng, class T, class Proj = identity,
        IndirectStrictWeakOrder<const T*, projected<iterator_t<Rng>, Proj>> Comp = less<>>
      safe_iterator_t<Rng>
        upper_bound(Rng&& rng, const T& value, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardIterator I, Sentinel<I> S, class T, class Proj = identity,
        IndirectStrictWeakOrder<const T*, projected<I, Proj>> Comp = less<>>
      tagged_pair<tag::begin(I), tag::end(I)>
        equal_range(I first, S last, const T& value, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardRange Rng, class T, class Proj = identity,
        IndirectStrictWeakOrder<const T*, projected<iterator_t<Rng>, Proj>> Comp = less<>>
      tagged_pair<tag::begin(safe_iterator_t<Rng>),
                  tag::end(safe_iterator_t<Rng>)>
        equal_range(Rng&& rng, const T& value, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardIterator I, Sentinel<I> S, class T, class Proj = identity,
        IndirectStrictWeakOrder<const T*, projected<I, Proj>> Comp = less<>>
      bool
        binary_search(I first, S last, const T& value, Comp comp = Comp{},
                      Proj proj = Proj{});

    template <ForwardRange Rng, class T, class Proj = identity,
        IndirectStrictWeakOrder<const T*, projected<iterator_t<Rng>, Proj>> Comp = less<>>
      bool
        binary_search(Rng&& rng, const T& value, Comp comp = Comp{},
                      Proj proj = Proj{});

    template <InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
        WeaklyIncrementable O, class Comp = less<>, class Proj1 = identity,
        class Proj2 = identity>
      requires Mergeable<I1, I2, O, Comp, Proj1, Proj2>
      tagged_tuple<tag::in1(I1), tag::in2(I2), tag::out(O)>
        merge(I1 first1, S1 last1, I2 first2, S2 last2, O result,
              Comp comp = Comp{}, Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputRange Rng1, InputRange Rng2, WeaklyIncrementable O, class Comp = less<>,
        class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<iterator_t<Rng1>, iterator_t<Rng2>, O, Comp, Proj1, Proj2>
      tagged_tuple<tag::in1(safe_iterator_t<Rng1>),
                   tag::in2(safe_iterator_t<Rng2>),
                   tag::out(O)>
        merge(Rng1&& rng1, Rng2&& rng2, O result,
              Comp comp = Comp{}, Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <BidirectionalIterator I, Sentinel<I> S, class Comp = less<>,
        class Proj = identity>
      requires Sortable<I, Comp, Proj>
      I
        inplace_merge(I first, I middle, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <BidirectionalRange Rng, class Comp = less<>, class Proj = identity>
      requires Sortable<iterator_t<Rng>, Comp, Proj>
      safe_iterator_t<Rng>
        inplace_merge(Rng&& rng, iterator_t<Rng> middle, Comp comp = Comp{},
                      Proj proj = Proj{});

    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 = less<>>
      bool
        includes(I1 first1, S1 last1, I2 first2, S2 last2, Comp comp = Comp{},
                 Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputRange Rng1, InputRange Rng2, class Proj1 = identity,
        class Proj2 = identity,
        IndirectStrictWeakOrder<projected<iterator_t<Rng1>, Proj1>,
          projected<iterator_t<Rng2>, Proj2>> Comp = less<>>
      bool
        includes(Rng1&& rng1, Rng2&& rng2, Comp comp = Comp{},
                 Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
        WeaklyIncrementable O, class Comp = less<>,
        class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<I1, I2, O, Comp, Proj1, Proj2>
      tagged_tuple<tag::in1(I1), tag::in2(I2), tag::out(O)>
        set_union(I1 first1, S1 last1, I2 first2, S2 last2, O result, Comp comp = Comp{},
                  Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputRange Rng1, InputRange Rng2, WeaklyIncrementable O,
        class Comp = less<>, class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<iterator_t<Rng1>, iterator_t<Rng2>, O, Comp, Proj1, Proj2>
      tagged_tuple<tag::in1(safe_iterator_t<Rng1>),
                   tag::in2(safe_iterator_t<Rng2>),
                   tag::out(O)>
        set_union(Rng1&& rng1, Rng2&& rng2, O result, Comp comp = Comp{},
                  Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
        WeaklyIncrementable O, class Comp = less<>,
        class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<I1, I2, O, Comp, Proj1, Proj2>
      O
        set_intersection(I1 first1, S1 last1, I2 first2, S2 last2, O result,
                         Comp comp = Comp{}, Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputRange Rng1, InputRange Rng2, WeaklyIncrementable O,
        class Comp = less<>, class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<iterator_t<Rng1>, iterator_t<Rng2>, O, Comp, Proj1, Proj2>
      O
        set_intersection(Rng1&& rng1, Rng2&& rng2, O result,
                         Comp comp = Comp{}, Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
        WeaklyIncrementable O, class Comp = less<>,
        class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<I1, I2, O, Comp, Proj1, Proj2>
      tagged_pair<tag::in1(I1), tag::out(O)>
        set_difference(I1 first1, S1 last1, I2 first2, S2 last2, O result,
                       Comp comp = Comp{}, Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputRange Rng1, InputRange Rng2, WeaklyIncrementable O,
        class Comp = less<>, class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<iterator_t<Rng1>, iterator_t<Rng2>, O, Comp, Proj1, Proj2>
      tagged_pair<tag::in1(safe_iterator_t<Rng1>), tag::out(O)>
        set_difference(Rng1&& rng1, Rng2&& rng2, O result,
                       Comp comp = Comp{}, Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputIterator I1, Sentinel<I1> S1, InputIterator I2, Sentinel<I2> S2,
        WeaklyIncrementable O, class Comp = less<>,
        class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<I1, I2, O, Comp, Proj1, Proj2>
      tagged_tuple<tag::in1(I1), tag::in2(I2), tag::out(O)>
        set_symmetric_difference(I1 first1, S1 last1, I2 first2, S2 last2, O result,
                                 Comp comp = Comp{}, Proj1 proj1 = Proj1{},
                                 Proj2 proj2 = Proj2{});

    template <InputRange Rng1, InputRange Rng2, WeaklyIncrementable O,
        class Comp = less<>, class Proj1 = identity, class Proj2 = identity>
      requires Mergeable<iterator_t<Rng1>, iterator_t<Rng2>, O, Comp, Proj1, Proj2>
      tagged_tuple<tag::in1(safe_iterator_t<Rng1>),
                   tag::in2(safe_iterator_t<Rng2>),
                   tag::out(O)>
        set_symmetric_difference(Rng1&& rng1, Rng2&& rng2, O result, Comp comp = Comp{},
                                 Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <RandomAccessIterator I, Sentinel<I> S, class Comp = less<>,
        class Proj = identity>
      requires Sortable<I, Comp, Proj>
      I push_heap(I first, S last, Comp comp = Comp{}, Proj proj == Proj{});

    template <RandomAccessRange Rng, class Comp = less<>, class Proj = identity>
      requires Sortable<iterator_t<Rng>, Comp, Proj>
      safe_iterator_t<Rng>
        push_heap(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessIterator I, Sentinel<I> S, class Comp = less<>,
        class Proj = identity>
      requires Sortable<I, Comp, Proj>
      I pop_heap(I first, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessRange Rng, class Comp = less<>, class Proj = identity>
      requires Sortable<iterator_t<Rng>, Comp, Proj>
      safe_iterator_t<Rng>
        pop_heap(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessIterator I, Sentinel<I> S, class Comp = less<>,
        class Proj = identity>
      requires Sortable<I, Comp, Proj>
      I make_heap(I first, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessRange Rng, class Comp = less<>, class Proj = identity>
      requires Sortable<iterator_t<Rng>, Comp, Proj>
      safe_iterator_t<Rng>
        make_heap(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessIterator I, Sentinel<I> S, class Comp = less<>,
        class Proj = identity>
      requires Sortable<I, Comp, Proj>
      I sort_heap(I first, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessRange Rng, class Comp = less<>, class Proj = identity>
      requires Sortable<iterator_t<Rng>, Comp, Proj>
      safe_iterator_t<Rng>
        sort_heap(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessIterator I, Sentinel<I> S, class Proj = identity,
        IndirectStrictWeakOrder<projected<I, Proj>> Comp = less<>>
      bool is_heap(I first, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessRange Rng, class Proj = identity,
        IndirectStrictWeakOrder<projected<iterator_t<Rng>, Proj>> Comp = less<>>
      bool
        is_heap(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessIterator I, Sentinel<I> S, class Proj = identity,
        IndirectStrictWeakOrder<projected<I, Proj>> Comp = less<>>
      I is_heap_until(I first, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <RandomAccessRange Rng, class Proj = identity,
        IndirectStrictWeakOrder<projected<iterator_t<Rng>, Proj>> Comp = less<>>
      safe_iterator_t<Rng>
        is_heap_until(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <class T, class Proj = identity,
        IndirectStrictWeakOrder<projected<const T*, Proj>> Comp = less<>>
      constexpr const T& min(const T& a, const T& b, Comp comp = Comp{}, Proj proj = Proj{});

    template <Copyable T, class Proj = identity,
        IndirectStrictWeakOrder<projected<const T*, Proj>> Comp = less<>>
      constexpr T min(initializer_list<T> t, Comp comp = Comp{}, Proj proj = Proj{});

    template <InputRange Rng, class Proj = identity,
        IndirectStrictWeakOrder<projected<iterator_t<Rng>, Proj>> Comp = less<>>
      requires Copyable<value_type_t<iterator_t<Rng>>>
      value_type_t<iterator_t<Rng>>
        min(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <class T, class Proj = identity,
        IndirectStrictWeakOrder<projected<const T*, Proj>> Comp = less<>>
      constexpr const T& max(const T& a, const T& b, Comp comp = Comp{}, Proj proj = Proj{});

    template <Copyable T, class Proj = identity,
        IndirectStrictWeakOrder<projected<const T*, Proj>> Comp = less<>>
      constexpr T max(initializer_list<T> t, Comp comp = Comp{}, Proj proj = Proj{});

    template <InputRange Rng, class Proj = identity,
        IndirectStrictWeakOrder<projected<iterator_t<Rng>, Proj>> Comp = less<>>
      requires Copyable<value_type_t<iterator_t<Rng>>>
      value_type_t<iterator_t<Rng>>
        max(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <class T, class Proj = identity,
        IndirectStrictWeakOrder<projected<const T*, Proj>> Comp = less<>>
      constexpr tagged_pair<tag::min(const T&), tag::max(const T&)>
        minmax(const T& a, const T& b, Comp comp = Comp{}, Proj proj = Proj{});

    template <Copyable T, class Proj = identity,
        IndirectStrictWeakOrder<projected<const T*, Proj>> Comp = less<>>
      constexpr tagged_pair<tag::min(T), tag::max(T)>
        minmax(initializer_list<T> t, Comp comp = Comp{}, Proj proj = Proj{});

    template <InputRange Rng, class Proj = identity,
        IndirectStrictWeakOrder<projected<iterator_t<Rng>, Proj>> Comp = less<>>
      requires Copyable<value_type_t<iterator_t<Rng>>>
      tagged_pair<tag::min(value_type_t<iterator_t<Rng>>),
                  tag::max(value_type_t<iterator_t<Rng>>)>
        minmax(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardIterator I, Sentinel<I> S, class Proj = identity,
        IndirectStrictWeakOrder<projected<I, Proj>> Comp = less<>>
      I min_element(I first, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardRange Rng, class Proj = identity,
        IndirectStrictWeakOrder<projected<iterator_t<Rng>, Proj>> Comp = less<>>
      safe_iterator_t<Rng>
        min_element(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardIterator I, Sentinel<I> S, class Proj = identity,
        IndirectStrictWeakOrder<projected<I, Proj>> Comp = less<>>
      I max_element(I first, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardRange Rng, class Proj = identity,
        IndirectStrictWeakOrder<projected<iterator_t<Rng>, Proj>> Comp = less<>>
      safe_iterator_t<Rng>
        max_element(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardIterator I, Sentinel<I> S, class Proj = identity,
        IndirectStrictWeakOrder<projected<I, Proj>> Comp = less<>>
      tagged_pair<tag::min(I), tag::max(I)>
        minmax_element(I first, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <ForwardRange Rng, class Proj = identity,
        IndirectStrictWeakOrder<projected<iterator_t<Rng>, Proj>> Comp = less<>>
      tagged_pair<tag::min(safe_iterator_t<Rng>),
                  tag::max(safe_iterator_t<Rng>)>
        minmax_element(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    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 = less<>>
      bool
        lexicographical_compare(I1 first1, S1 last1, I2 first2, S2 last2,
                                Comp comp = Comp{},
                                Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <InputRange Rng1, InputRange Rng2, class Proj1 = identity,
        class Proj2 = identity,
        IndirectStrictWeakOrder<projected<iterator_t<Rng1>, Proj1>,
          projected<iterator_t<Rng2>, Proj2>> Comp = less<>>
      bool
        lexicographical_compare(Rng1&& rng1, Rng2&& rng2, Comp comp = Comp{},
                                Proj1 proj1 = Proj1{}, Proj2 proj2 = Proj2{});

    template <BidirectionalIterator I, Sentinel<I> S, class Comp = less<>,
        class Proj = identity>
      requires Sortable<I, Comp, Proj>
      bool next_permutation(I first, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <BidirectionalRange Rng, class Comp = less<>,
        class Proj = identity>
      requires Sortable<iterator_t<Rng>, Comp, Proj>
      bool
        next_permutation(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    template <BidirectionalIterator I, Sentinel<I> S, class Comp = less<>,
        class Proj = identity>
      requires Sortable<I, Comp, Proj>
      bool prev_permutation(I first, S last, Comp comp = Comp{}, Proj proj = Proj{});

    template <BidirectionalRange Rng, class Comp = less<>,
        class Proj = identity>
      requires Sortable<iterator_t<Rng>, Comp, Proj>
      bool
        prev_permutation(Rng&& rng, Comp comp = Comp{}, Proj proj = Proj{});

    }}}}