// Core algorithmic facilities -*- C++ -*-
// Copyright (C) 2020 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// .
/** @file bits/ranges_algo.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{algorithm}
*/
#ifndef _RANGES_ALGO_H
#define _RANGES_ALGO_H 1
#if __cplusplus > 201703L
#include
#include // concept uniform_random_bit_generator
#if __cpp_lib_concepts
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
namespace ranges
{
namespace __detail
{
template
constexpr auto
__make_comp_proj(_Comp& __comp, _Proj& __proj)
{
return [&] (auto&& __lhs, auto&& __rhs) -> bool {
using _TL = decltype(__lhs);
using _TR = decltype(__rhs);
return std::__invoke(__comp,
std::__invoke(__proj, std::forward<_TL>(__lhs)),
std::__invoke(__proj, std::forward<_TR>(__rhs)));
};
}
template
constexpr auto
__make_pred_proj(_Pred& __pred, _Proj& __proj)
{
return [&] (_Tp&& __arg) -> bool {
return std::__invoke(__pred,
std::__invoke(__proj, std::forward<_Tp>(__arg)));
};
}
} // namespace __detail
struct __all_of_fn
{
template _Sent,
typename _Proj = identity,
indirect_unary_predicate> _Pred>
constexpr bool
operator()(_Iter __first, _Sent __last,
_Pred __pred, _Proj __proj = {}) const
{
for (; __first != __last; ++__first)
if (!(bool)std::__invoke(__pred, std::__invoke(__proj, *__first)))
return false;
return true;
}
template, _Proj>>
_Pred>
constexpr bool
operator()(_Range&& __r, _Pred __pred, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__pred), std::move(__proj));
}
};
inline constexpr __all_of_fn all_of{};
struct __any_of_fn
{
template _Sent,
typename _Proj = identity,
indirect_unary_predicate> _Pred>
constexpr bool
operator()(_Iter __first, _Sent __last,
_Pred __pred, _Proj __proj = {}) const
{
for (; __first != __last; ++__first)
if (std::__invoke(__pred, std::__invoke(__proj, *__first)))
return true;
return false;
}
template, _Proj>>
_Pred>
constexpr bool
operator()(_Range&& __r, _Pred __pred, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__pred), std::move(__proj));
}
};
inline constexpr __any_of_fn any_of{};
struct __none_of_fn
{
template _Sent,
typename _Proj = identity,
indirect_unary_predicate> _Pred>
constexpr bool
operator()(_Iter __first, _Sent __last,
_Pred __pred, _Proj __proj = {}) const
{
for (; __first != __last; ++__first)
if (std::__invoke(__pred, std::__invoke(__proj, *__first)))
return false;
return true;
}
template, _Proj>>
_Pred>
constexpr bool
operator()(_Range&& __r, _Pred __pred, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__pred), std::move(__proj));
}
};
inline constexpr __none_of_fn none_of{};
template
struct in_fun_result
{
[[no_unique_address]] _Iter in;
[[no_unique_address]] _Fp fun;
template
requires convertible_to
&& convertible_to
constexpr
operator in_fun_result<_Iter2, _F2p>() const &
{ return {in, fun}; }
template
requires convertible_to<_Iter, _Iter2> && convertible_to<_Fp, _F2p>
constexpr
operator in_fun_result<_Iter2, _F2p>() &&
{ return {std::move(in), std::move(fun)}; }
};
template
using for_each_result = in_fun_result<_Iter, _Fp>;
struct __for_each_fn
{
template _Sent,
typename _Proj = identity,
indirectly_unary_invocable> _Fun>
constexpr for_each_result<_Iter, _Fun>
operator()(_Iter __first, _Sent __last, _Fun __f, _Proj __proj = {}) const
{
for (; __first != __last; ++__first)
std::__invoke(__f, std::__invoke(__proj, *__first));
return { std::move(__first), std::move(__f) };
}
template, _Proj>>
_Fun>
constexpr for_each_result, _Fun>
operator()(_Range&& __r, _Fun __f, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__f), std::move(__proj));
}
};
inline constexpr __for_each_fn for_each{};
template
using for_each_n_result = in_fun_result<_Iter, _Fp>;
struct __for_each_n_fn
{
template> _Fun>
constexpr for_each_n_result<_Iter, _Fun>
operator()(_Iter __first, iter_difference_t<_Iter> __n,
_Fun __f, _Proj __proj = {}) const
{
if constexpr (random_access_iterator<_Iter>)
{
if (__n <= 0)
return {std::move(__first), std::move(__f)};
auto __last = __first + __n;
return ranges::for_each(std::move(__first), std::move(__last),
std::move(__f), std::move(__proj));
}
else
{
while (__n-- > 0)
{
std::__invoke(__f, std::__invoke(__proj, *__first));
++__first;
}
return {std::move(__first), std::move(__f)};
}
}
};
inline constexpr __for_each_n_fn for_each_n{};
struct __find_fn
{
template _Sent, typename _Tp,
typename _Proj = identity>
requires indirect_binary_predicate, const _Tp*>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
const _Tp& __value, _Proj __proj = {}) const
{
while (__first != __last
&& !(std::__invoke(__proj, *__first) == __value))
++__first;
return __first;
}
template
requires indirect_binary_predicate, _Proj>,
const _Tp*>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r, const _Tp& __value, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
__value, std::move(__proj));
}
};
inline constexpr __find_fn find{};
struct __find_if_fn
{
template _Sent,
typename _Proj = identity,
indirect_unary_predicate> _Pred>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
_Pred __pred, _Proj __proj = {}) const
{
while (__first != __last
&& !(bool)std::__invoke(__pred, std::__invoke(__proj, *__first)))
++__first;
return __first;
}
template, _Proj>>
_Pred>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r, _Pred __pred, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__pred), std::move(__proj));
}
};
inline constexpr __find_if_fn find_if{};
struct __find_if_not_fn
{
template _Sent,
typename _Proj = identity,
indirect_unary_predicate> _Pred>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
_Pred __pred, _Proj __proj = {}) const
{
while (__first != __last
&& (bool)std::__invoke(__pred, std::__invoke(__proj, *__first)))
++__first;
return __first;
}
template, _Proj>>
_Pred>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r, _Pred __pred, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__pred), std::move(__proj));
}
};
inline constexpr __find_if_not_fn find_if_not{};
struct __find_first_of_fn
{
template _Sent1,
forward_iterator _Iter2, sentinel_for<_Iter2> _Sent2,
typename _Pred = ranges::equal_to,
typename _Proj1 = identity, typename _Proj2 = identity>
requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
constexpr _Iter1
operator()(_Iter1 __first1, _Sent1 __last1,
_Iter2 __first2, _Sent2 __last2, _Pred __pred = {},
_Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
{
for (; __first1 != __last1; ++__first1)
for (auto __iter = __first2; __iter != __last2; ++__iter)
if (std::__invoke(__pred,
std::__invoke(__proj1, *__first1),
std::__invoke(__proj2, *__iter)))
return __first1;
return __first1;
}
template
requires indirectly_comparable, iterator_t<_Range2>,
_Pred, _Proj1, _Proj2>
constexpr borrowed_iterator_t<_Range1>
operator()(_Range1&& __r1, _Range2&& __r2, _Pred __pred = {},
_Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
{
return (*this)(ranges::begin(__r1), ranges::end(__r1),
ranges::begin(__r2), ranges::end(__r2),
std::move(__pred),
std::move(__proj1), std::move(__proj2));
}
};
inline constexpr __find_first_of_fn find_first_of{};
struct __count_fn
{
template _Sent,
typename _Tp, typename _Proj = identity>
requires indirect_binary_predicate,
const _Tp*>
constexpr iter_difference_t<_Iter>
operator()(_Iter __first, _Sent __last,
const _Tp& __value, _Proj __proj = {}) const
{
iter_difference_t<_Iter> __n = 0;
for (; __first != __last; ++__first)
if (std::__invoke(__proj, *__first) == __value)
++__n;
return __n;
}
template
requires indirect_binary_predicate, _Proj>,
const _Tp*>
constexpr range_difference_t<_Range>
operator()(_Range&& __r, const _Tp& __value, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
__value, std::move(__proj));
}
};
inline constexpr __count_fn count{};
struct __count_if_fn
{
template _Sent,
typename _Proj = identity,
indirect_unary_predicate> _Pred>
constexpr iter_difference_t<_Iter>
operator()(_Iter __first, _Sent __last,
_Pred __pred, _Proj __proj = {}) const
{
iter_difference_t<_Iter> __n = 0;
for (; __first != __last; ++__first)
if (std::__invoke(__pred, std::__invoke(__proj, *__first)))
++__n;
return __n;
}
template, _Proj>>
_Pred>
constexpr range_difference_t<_Range>
operator()(_Range&& __r, _Pred __pred, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__pred), std::move(__proj));
}
};
inline constexpr __count_if_fn count_if{};
template
struct in_in_result
{
[[no_unique_address]] _Iter1 in1;
[[no_unique_address]] _Iter2 in2;
template
requires convertible_to
&& convertible_to
constexpr
operator in_in_result<_IIter1, _IIter2>() const &
{ return {in1, in2}; }
template
requires convertible_to<_Iter1, _IIter1>
&& convertible_to<_Iter2, _IIter2>
constexpr
operator in_in_result<_IIter1, _IIter2>() &&
{ return {std::move(in1), std::move(in2)}; }
};
template
using mismatch_result = in_in_result<_Iter1, _Iter2>;
struct __mismatch_fn
{
template _Sent1,
input_iterator _Iter2, sentinel_for<_Iter2> _Sent2,
typename _Pred = ranges::equal_to,
typename _Proj1 = identity, typename _Proj2 = identity>
requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
constexpr mismatch_result<_Iter1, _Iter2>
operator()(_Iter1 __first1, _Sent1 __last1,
_Iter2 __first2, _Sent2 __last2, _Pred __pred = {},
_Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
{
while (__first1 != __last1 && __first2 != __last2
&& (bool)std::__invoke(__pred,
std::__invoke(__proj1, *__first1),
std::__invoke(__proj2, *__first2)))
{
++__first1;
++__first2;
}
return { std::move(__first1), std::move(__first2) };
}
template
requires indirectly_comparable, iterator_t<_Range2>,
_Pred, _Proj1, _Proj2>
constexpr mismatch_result, iterator_t<_Range2>>
operator()(_Range1&& __r1, _Range2&& __r2, _Pred __pred = {},
_Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
{
return (*this)(ranges::begin(__r1), ranges::end(__r1),
ranges::begin(__r2), ranges::end(__r2),
std::move(__pred),
std::move(__proj1), std::move(__proj2));
}
};
inline constexpr __mismatch_fn mismatch{};
struct __search_fn
{
template _Sent1,
forward_iterator _Iter2, sentinel_for<_Iter2> _Sent2,
typename _Pred = ranges::equal_to,
typename _Proj1 = identity, typename _Proj2 = identity>
requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
constexpr subrange<_Iter1>
operator()(_Iter1 __first1, _Sent1 __last1,
_Iter2 __first2, _Sent2 __last2, _Pred __pred = {},
_Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
{
if (__first1 == __last1 || __first2 == __last2)
return {__first1, __first1};
for (;;)
{
for (;;)
{
if (__first1 == __last1)
return {__first1, __first1};
if (std::__invoke(__pred,
std::__invoke(__proj1, *__first1),
std::__invoke(__proj2, *__first2)))
break;
++__first1;
}
auto __cur1 = __first1;
auto __cur2 = __first2;
for (;;)
{
if (++__cur2 == __last2)
return {__first1, ++__cur1};
if (++__cur1 == __last1)
return {__cur1, __cur1};
if (!(bool)std::__invoke(__pred,
std::__invoke(__proj1, *__cur1),
std::__invoke(__proj2, *__cur2)))
{
++__first1;
break;
}
}
}
}
template
requires indirectly_comparable, iterator_t<_Range2>,
_Pred, _Proj1, _Proj2>
constexpr borrowed_subrange_t<_Range1>
operator()(_Range1&& __r1, _Range2&& __r2, _Pred __pred = {},
_Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
{
return (*this)(ranges::begin(__r1), ranges::end(__r1),
ranges::begin(__r2), ranges::end(__r2),
std::move(__pred),
std::move(__proj1), std::move(__proj2));
}
};
inline constexpr __search_fn search{};
struct __search_n_fn
{
template _Sent, typename _Tp,
typename _Pred = ranges::equal_to, typename _Proj = identity>
requires indirectly_comparable<_Iter, const _Tp*, _Pred, _Proj>
constexpr subrange<_Iter>
operator()(_Iter __first, _Sent __last, iter_difference_t<_Iter> __count,
const _Tp& __value, _Pred __pred = {}, _Proj __proj = {}) const
{
if (__count <= 0)
return {__first, __first};
auto __value_comp = [&] (_Rp&& __arg) -> bool {
return std::__invoke(__pred, std::forward<_Rp>(__arg), __value);
};
if (__count == 1)
{
__first = ranges::find_if(std::move(__first), __last,
std::move(__value_comp),
std::move(__proj));
if (__first == __last)
return {__first, __first};
else
{
auto __end = __first;
return {__first, ++__end};
}
}
if constexpr (sized_sentinel_for<_Sent, _Iter>
&& random_access_iterator<_Iter>)
{
auto __tail_size = __last - __first;
auto __remainder = __count;
while (__remainder <= __tail_size)
{
__first += __remainder;
__tail_size -= __remainder;
auto __backtrack = __first;
while (__value_comp(std::__invoke(__proj, *--__backtrack)))
{
if (--__remainder == 0)
return {__first - __count, __first};
}
__remainder = __count + 1 - (__first - __backtrack);
}
auto __i = __first + __tail_size;
return {__i, __i};
}
else
{
__first = ranges::find_if(__first, __last, __value_comp, __proj);
while (__first != __last)
{
auto __n = __count;
auto __i = __first;
++__i;
while (__i != __last && __n != 1
&& __value_comp(std::__invoke(__proj, *__i)))
{
++__i;
--__n;
}
if (__n == 1)
return {__first, __i};
if (__i == __last)
return {__i, __i};
__first = ranges::find_if(++__i, __last, __value_comp, __proj);
}
return {__first, __first};
}
}
template
requires indirectly_comparable, const _Tp*,
_Pred, _Proj>
constexpr borrowed_subrange_t<_Range>
operator()(_Range&& __r, range_difference_t<_Range> __count,
const _Tp& __value, _Pred __pred = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__count), __value,
std::move(__pred), std::move(__proj));
}
};
inline constexpr __search_n_fn search_n{};
struct __find_end_fn
{
template _Sent1,
forward_iterator _Iter2, sentinel_for<_Iter2> _Sent2,
typename _Pred = ranges::equal_to,
typename _Proj1 = identity, typename _Proj2 = identity>
requires indirectly_comparable<_Iter1, _Iter2, _Pred, _Proj1, _Proj2>
constexpr subrange<_Iter1>
operator()(_Iter1 __first1, _Sent1 __last1,
_Iter2 __first2, _Sent2 __last2, _Pred __pred = {},
_Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
{
if constexpr (bidirectional_iterator<_Iter1>
&& bidirectional_iterator<_Iter2>)
{
auto __i1 = ranges::next(__first1, __last1);
auto __i2 = ranges::next(__first2, __last2);
auto __rresult
= ranges::search(reverse_iterator<_Iter1>{__i1},
reverse_iterator<_Iter1>{__first1},
reverse_iterator<_Iter2>{__i2},
reverse_iterator<_Iter2>{__first2},
std::move(__pred),
std::move(__proj1), std::move(__proj2));
auto __result_first = ranges::end(__rresult).base();
auto __result_last = ranges::begin(__rresult).base();
if (__result_last == __first1)
return {__i1, __i1};
else
return {__result_first, __result_last};
}
else
{
auto __i = ranges::next(__first1, __last1);
if (__first2 == __last2)
return {__i, __i};
auto __result_begin = __i;
auto __result_end = __i;
for (;;)
{
auto __new_range = ranges::search(__first1, __last1,
__first2, __last2,
__pred, __proj1, __proj2);
auto __new_result_begin = ranges::begin(__new_range);
auto __new_result_end = ranges::end(__new_range);
if (__new_result_begin == __last1)
return {__result_begin, __result_end};
else
{
__result_begin = __new_result_begin;
__result_end = __new_result_end;
__first1 = __result_begin;
++__first1;
}
}
}
}
template
requires indirectly_comparable, iterator_t<_Range2>,
_Pred, _Proj1, _Proj2>
constexpr borrowed_subrange_t<_Range1>
operator()(_Range1&& __r1, _Range2&& __r2, _Pred __pred = {},
_Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
{
return (*this)(ranges::begin(__r1), ranges::end(__r1),
ranges::begin(__r2), ranges::end(__r2),
std::move(__pred),
std::move(__proj1), std::move(__proj2));
}
};
inline constexpr __find_end_fn find_end{};
struct __adjacent_find_fn
{
template _Sent,
typename _Proj = identity,
indirect_binary_predicate,
projected<_Iter, _Proj>> _Pred
= ranges::equal_to>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
_Pred __pred = {}, _Proj __proj = {}) const
{
if (__first == __last)
return __first;
auto __next = __first;
for (; ++__next != __last; __first = __next)
{
if (std::__invoke(__pred,
std::__invoke(__proj, *__first),
std::__invoke(__proj, *__next)))
return __first;
}
return __next;
}
template, _Proj>,
projected, _Proj>> _Pred = ranges::equal_to>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r, _Pred __pred = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__pred), std::move(__proj));
}
};
inline constexpr __adjacent_find_fn adjacent_find{};
struct __is_permutation_fn
{
template _Sent1,
forward_iterator _Iter2, sentinel_for<_Iter2> _Sent2,
typename _Proj1 = identity, typename _Proj2 = identity,
indirect_equivalence_relation,
projected<_Iter2, _Proj2>> _Pred
= ranges::equal_to>
constexpr bool
operator()(_Iter1 __first1, _Sent1 __last1,
_Iter2 __first2, _Sent2 __last2, _Pred __pred = {},
_Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
{
constexpr bool __sized_iters
= (sized_sentinel_for<_Sent1, _Iter1>
&& sized_sentinel_for<_Sent2, _Iter2>);
if constexpr (__sized_iters)
{
auto __d1 = ranges::distance(__first1, __last1);
auto __d2 = ranges::distance(__first2, __last2);
if (__d1 != __d2)
return false;
}
// Efficiently compare identical prefixes: O(N) if sequences
// have the same elements in the same order.
for (; __first1 != __last1 && __first2 != __last2;
++__first1, (void)++__first2)
if (!(bool)std::__invoke(__pred,
std::__invoke(__proj1, *__first1),
std::__invoke(__proj2, *__first2)))
break;
if constexpr (__sized_iters)
{
if (__first1 == __last1)
return true;
}
else
{
auto __d1 = ranges::distance(__first1, __last1);
auto __d2 = ranges::distance(__first2, __last2);
if (__d1 == 0 && __d2 == 0)
return true;
if (__d1 != __d2)
return false;
}
for (auto __scan = __first1; __scan != __last1; ++__scan)
{
auto&& __proj_scan = std::__invoke(__proj1, *__scan);
auto __comp_scan = [&] (_Tp&& __arg) -> bool {
return std::__invoke(__pred, __proj_scan,
std::forward<_Tp>(__arg));
};
if (__scan != ranges::find_if(__first1, __scan,
__comp_scan, __proj1))
continue; // We've seen this one before.
auto __matches = ranges::count_if(__first2, __last2,
__comp_scan, __proj2);
if (__matches == 0
|| ranges::count_if(__scan, __last1,
__comp_scan, __proj1) != __matches)
return false;
}
return true;
}
template, _Proj1>,
projected, _Proj2>> _Pred = ranges::equal_to>
constexpr bool
operator()(_Range1&& __r1, _Range2&& __r2, _Pred __pred = {},
_Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
{
return (*this)(ranges::begin(__r1), ranges::end(__r1),
ranges::begin(__r2), ranges::end(__r2),
std::move(__pred),
std::move(__proj1), std::move(__proj2));
}
};
inline constexpr __is_permutation_fn is_permutation{};
template
using copy_if_result = in_out_result<_Iter, _Out>;
struct __copy_if_fn
{
template _Sent,
weakly_incrementable _Out, typename _Proj = identity,
indirect_unary_predicate> _Pred>
requires indirectly_copyable<_Iter, _Out>
constexpr copy_if_result<_Iter, _Out>
operator()(_Iter __first, _Sent __last, _Out __result,
_Pred __pred, _Proj __proj = {}) const
{
for (; __first != __last; ++__first)
if (std::__invoke(__pred, std::__invoke(__proj, *__first)))
{
*__result = *__first;
++__result;
}
return {std::move(__first), std::move(__result)};
}
template, _Proj>>
_Pred>
requires indirectly_copyable, _Out>
constexpr copy_if_result, _Out>
operator()(_Range&& __r, _Out __result,
_Pred __pred, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__result),
std::move(__pred), std::move(__proj));
}
};
inline constexpr __copy_if_fn copy_if{};
template
using swap_ranges_result = in_in_result<_Iter1, _Iter2>;
struct __swap_ranges_fn
{
template _Sent1,
input_iterator _Iter2, sentinel_for<_Iter2> _Sent2>
requires indirectly_swappable<_Iter1, _Iter2>
constexpr swap_ranges_result<_Iter1, _Iter2>
operator()(_Iter1 __first1, _Sent1 __last1,
_Iter2 __first2, _Sent2 __last2) const
{
for (; __first1 != __last1 && __first2 != __last2;
++__first1, (void)++__first2)
ranges::iter_swap(__first1, __first2);
return {std::move(__first1), std::move(__first2)};
}
template
requires indirectly_swappable, iterator_t<_Range2>>
constexpr swap_ranges_result,
borrowed_iterator_t<_Range2>>
operator()(_Range1&& __r1, _Range2&& __r2) const
{
return (*this)(ranges::begin(__r1), ranges::end(__r1),
ranges::begin(__r2), ranges::end(__r2));
}
};
inline constexpr __swap_ranges_fn swap_ranges{};
template
using unary_transform_result = in_out_result<_Iter, _Out>;
template
struct in_in_out_result
{
[[no_unique_address]] _Iter1 in1;
[[no_unique_address]] _Iter2 in2;
[[no_unique_address]] _Out out;
template
requires convertible_to
&& convertible_to
&& convertible_to
constexpr
operator in_in_out_result<_IIter1, _IIter2, _OOut>() const &
{ return {in1, in2, out}; }
template
requires convertible_to<_Iter1, _IIter1>
&& convertible_to<_Iter2, _IIter2>
&& convertible_to<_Out, _OOut>
constexpr
operator in_in_out_result<_IIter1, _IIter2, _OOut>() &&
{ return {std::move(in1), std::move(in2), std::move(out)}; }
};
template
using binary_transform_result = in_in_out_result<_Iter1, _Iter2, _Out>;
struct __transform_fn
{
template _Sent,
weakly_incrementable _Out,
copy_constructible _Fp, typename _Proj = identity>
requires indirectly_writable<_Out,
indirect_result_t<_Fp&,
projected<_Iter, _Proj>>>
constexpr unary_transform_result<_Iter, _Out>
operator()(_Iter __first1, _Sent __last1, _Out __result,
_Fp __op, _Proj __proj = {}) const
{
for (; __first1 != __last1; ++__first1, (void)++__result)
*__result = std::__invoke(__op, std::__invoke(__proj, *__first1));
return {std::move(__first1), std::move(__result)};
}
template
requires indirectly_writable<_Out,
indirect_result_t<_Fp&,
projected, _Proj>>>
constexpr unary_transform_result, _Out>
operator()(_Range&& __r, _Out __result, _Fp __op, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__result),
std::move(__op), std::move(__proj));
}
template _Sent1,
input_iterator _Iter2, sentinel_for<_Iter2> _Sent2,
weakly_incrementable _Out, copy_constructible _Fp,
typename _Proj1 = identity, typename _Proj2 = identity>
requires indirectly_writable<_Out,
indirect_result_t<_Fp&,
projected<_Iter1, _Proj1>,
projected<_Iter2, _Proj2>>>
constexpr binary_transform_result<_Iter1, _Iter2, _Out>
operator()(_Iter1 __first1, _Sent1 __last1,
_Iter2 __first2, _Sent2 __last2,
_Out __result, _Fp __binary_op,
_Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
{
for (; __first1 != __last1 && __first2 != __last2;
++__first1, (void)++__first2, ++__result)
*__result = std::__invoke(__binary_op,
std::__invoke(__proj1, *__first1),
std::__invoke(__proj2, *__first2));
return {std::move(__first1), std::move(__first2), std::move(__result)};
}
template
requires indirectly_writable<_Out,
indirect_result_t<_Fp&,
projected, _Proj1>,
projected, _Proj2>>>
constexpr binary_transform_result,
borrowed_iterator_t<_Range2>, _Out>
operator()(_Range1&& __r1, _Range2&& __r2, _Out __result, _Fp __binary_op,
_Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
{
return (*this)(ranges::begin(__r1), ranges::end(__r1),
ranges::begin(__r2), ranges::end(__r2),
std::move(__result), std::move(__binary_op),
std::move(__proj1), std::move(__proj2));
}
};
inline constexpr __transform_fn transform{};
struct __replace_fn
{
template _Sent,
typename _Tp1, typename _Tp2, typename _Proj = identity>
requires indirectly_writable<_Iter, const _Tp2&>
&& indirect_binary_predicate,
const _Tp1*>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
const _Tp1& __old_value, const _Tp2& __new_value,
_Proj __proj = {}) const
{
for (; __first != __last; ++__first)
if (std::__invoke(__proj, *__first) == __old_value)
*__first = __new_value;
return __first;
}
template
requires indirectly_writable, const _Tp2&>
&& indirect_binary_predicate, _Proj>,
const _Tp1*>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r,
const _Tp1& __old_value, const _Tp2& __new_value,
_Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
__old_value, __new_value, std::move(__proj));
}
};
inline constexpr __replace_fn replace{};
struct __replace_if_fn
{
template _Sent,
typename _Tp, typename _Proj = identity,
indirect_unary_predicate> _Pred>
requires indirectly_writable<_Iter, const _Tp&>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
_Pred __pred, const _Tp& __new_value, _Proj __proj = {}) const
{
for (; __first != __last; ++__first)
if (std::__invoke(__pred, std::__invoke(__proj, *__first)))
*__first = __new_value;
return std::move(__first);
}
template, _Proj>>
_Pred>
requires indirectly_writable, const _Tp&>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r,
_Pred __pred, const _Tp& __new_value, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__pred), __new_value, std::move(__proj));
}
};
inline constexpr __replace_if_fn replace_if{};
template
using replace_copy_result = in_out_result<_Iter, _Out>;
struct __replace_copy_fn
{
template _Sent,
typename _Tp1, typename _Tp2, output_iterator _Out,
typename _Proj = identity>
requires indirectly_copyable<_Iter, _Out>
&& indirect_binary_predicate, const _Tp1*>
constexpr replace_copy_result<_Iter, _Out>
operator()(_Iter __first, _Sent __last, _Out __result,
const _Tp1& __old_value, const _Tp2& __new_value,
_Proj __proj = {}) const
{
for (; __first != __last; ++__first, (void)++__result)
if (std::__invoke(__proj, *__first) == __old_value)
*__result = __new_value;
else
*__result = *__first;
return {std::move(__first), std::move(__result)};
}
template _Out, typename _Proj = identity>
requires indirectly_copyable, _Out>
&& indirect_binary_predicate, _Proj>,
const _Tp1*>
constexpr replace_copy_result, _Out>
operator()(_Range&& __r, _Out __result,
const _Tp1& __old_value, const _Tp2& __new_value,
_Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__result), __old_value,
__new_value, std::move(__proj));
}
};
inline constexpr __replace_copy_fn replace_copy{};
template
using replace_copy_if_result = in_out_result<_Iter, _Out>;
struct __replace_copy_if_fn
{
template _Sent,
typename _Tp, output_iterator _Out,
typename _Proj = identity,
indirect_unary_predicate> _Pred>
requires indirectly_copyable<_Iter, _Out>
constexpr replace_copy_if_result<_Iter, _Out>
operator()(_Iter __first, _Sent __last, _Out __result,
_Pred __pred, const _Tp& __new_value, _Proj __proj = {}) const
{
for (; __first != __last; ++__first, (void)++__result)
if (std::__invoke(__pred, std::__invoke(__proj, *__first)))
*__result = __new_value;
else
*__result = *__first;
return {std::move(__first), std::move(__result)};
}
template _Out,
typename _Proj = identity,
indirect_unary_predicate, _Proj>>
_Pred>
requires indirectly_copyable, _Out>
constexpr replace_copy_if_result, _Out>
operator()(_Range&& __r, _Out __result,
_Pred __pred, const _Tp& __new_value, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__result), std::move(__pred),
__new_value, std::move(__proj));
}
};
inline constexpr __replace_copy_if_fn replace_copy_if{};
struct __generate_n_fn
{
template
requires invocable<_Fp&>
&& indirectly_writable<_Out, invoke_result_t<_Fp&>>
constexpr _Out
operator()(_Out __first, iter_difference_t<_Out> __n, _Fp __gen) const
{
for (; __n > 0; --__n, (void)++__first)
*__first = std::__invoke(__gen);
return __first;
}
};
inline constexpr __generate_n_fn generate_n{};
struct __generate_fn
{
template _Sent,
copy_constructible _Fp>
requires invocable<_Fp&>
&& indirectly_writable<_Out, invoke_result_t<_Fp&>>
constexpr _Out
operator()(_Out __first, _Sent __last, _Fp __gen) const
{
for (; __first != __last; ++__first)
*__first = std::__invoke(__gen);
return __first;
}
template
requires invocable<_Fp&> && output_range<_Range, invoke_result_t<_Fp&>>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r, _Fp __gen) const
{
return (*this)(ranges::begin(__r), ranges::end(__r), std::move(__gen));
}
};
inline constexpr __generate_fn generate{};
struct __remove_if_fn
{
template _Sent,
typename _Proj = identity,
indirect_unary_predicate> _Pred>
constexpr subrange<_Iter>
operator()(_Iter __first, _Sent __last,
_Pred __pred, _Proj __proj = {}) const
{
__first = ranges::find_if(__first, __last, __pred, __proj);
if (__first == __last)
return {__first, __first};
auto __result = __first;
++__first;
for (; __first != __last; ++__first)
if (!std::__invoke(__pred, std::__invoke(__proj, *__first)))
{
*__result = std::move(*__first);
++__result;
}
return {__result, __first};
}
template, _Proj>>
_Pred>
requires permutable>
constexpr borrowed_subrange_t<_Range>
operator()(_Range&& __r, _Pred __pred, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__pred), std::move(__proj));
}
};
inline constexpr __remove_if_fn remove_if{};
struct __remove_fn
{
template _Sent,
typename _Tp, typename _Proj = identity>
requires indirect_binary_predicate,
const _Tp*>
constexpr subrange<_Iter>
operator()(_Iter __first, _Sent __last,
const _Tp& __value, _Proj __proj = {}) const
{
auto __pred = [&] (auto&& __arg) -> bool {
return std::forward(__arg) == __value;
};
return ranges::remove_if(__first, __last,
std::move(__pred), std::move(__proj));
}
template
requires permutable>
&& indirect_binary_predicate, _Proj>,
const _Tp*>
constexpr borrowed_subrange_t<_Range>
operator()(_Range&& __r, const _Tp& __value, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
__value, std::move(__proj));
}
};
inline constexpr __remove_fn remove{};
template
using remove_copy_if_result = in_out_result<_Iter, _Out>;
struct __remove_copy_if_fn
{
template _Sent,
weakly_incrementable _Out, typename _Proj = identity,
indirect_unary_predicate> _Pred>
requires indirectly_copyable<_Iter, _Out>
constexpr remove_copy_if_result<_Iter, _Out>
operator()(_Iter __first, _Sent __last, _Out __result,
_Pred __pred, _Proj __proj = {}) const
{
for (; __first != __last; ++__first)
if (!std::__invoke(__pred, std::__invoke(__proj, *__first)))
{
*__result = *__first;
++__result;
}
return {std::move(__first), std::move(__result)};
}
template, _Proj>>
_Pred>
requires indirectly_copyable, _Out>
constexpr remove_copy_if_result, _Out>
operator()(_Range&& __r, _Out __result,
_Pred __pred, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__result),
std::move(__pred), std::move(__proj));
}
};
inline constexpr __remove_copy_if_fn remove_copy_if{};
template
using remove_copy_result = in_out_result<_Iter, _Out>;
struct __remove_copy_fn
{
template _Sent,
weakly_incrementable _Out, typename _Tp, typename _Proj = identity>
requires indirectly_copyable<_Iter, _Out>
&& indirect_binary_predicate,
const _Tp*>
constexpr remove_copy_result<_Iter, _Out>
operator()(_Iter __first, _Sent __last, _Out __result,
const _Tp& __value, _Proj __proj = {}) const
{
for (; __first != __last; ++__first)
if (!(std::__invoke(__proj, *__first) == __value))
{
*__result = *__first;
++__result;
}
return {std::move(__first), std::move(__result)};
}
template
requires indirectly_copyable, _Out>
&& indirect_binary_predicate, _Proj>,
const _Tp*>
constexpr remove_copy_result, _Out>
operator()(_Range&& __r, _Out __result,
const _Tp& __value, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__result), __value, std::move(__proj));
}
};
inline constexpr __remove_copy_fn remove_copy{};
struct __unique_fn
{
template _Sent,
typename _Proj = identity,
indirect_equivalence_relation<
projected<_Iter, _Proj>> _Comp = ranges::equal_to>
constexpr subrange<_Iter>
operator()(_Iter __first, _Sent __last,
_Comp __comp = {}, _Proj __proj = {}) const
{
__first = ranges::adjacent_find(__first, __last, __comp, __proj);
if (__first == __last)
return {__first, __first};
auto __dest = __first;
++__first;
while (++__first != __last)
if (!std::__invoke(__comp,
std::__invoke(__proj, *__dest),
std::__invoke(__proj, *__first)))
*++__dest = std::move(*__first);
return {++__dest, __first};
}
template, _Proj>> _Comp = ranges::equal_to>
requires permutable>
constexpr borrowed_subrange_t<_Range>
operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__comp), std::move(__proj));
}
};
inline constexpr __unique_fn unique{};
namespace __detail
{
template
concept __can_reread_output = input_iterator<_Out>
&& same_as<_Tp, iter_value_t<_Out>>;
}
template
using unique_copy_result = in_out_result<_Iter, _Out>;
struct __unique_copy_fn
{
template _Sent,
weakly_incrementable _Out, typename _Proj = identity,
indirect_equivalence_relation<
projected<_Iter, _Proj>> _Comp = ranges::equal_to>
requires indirectly_copyable<_Iter, _Out>
&& (forward_iterator<_Iter>
|| __detail::__can_reread_output<_Out, iter_value_t<_Iter>>
|| indirectly_copyable_storable<_Iter, _Out>)
constexpr unique_copy_result<_Iter, _Out>
operator()(_Iter __first, _Sent __last, _Out __result,
_Comp __comp = {}, _Proj __proj = {}) const
{
if (__first == __last)
return {std::move(__first), std::move(__result)};
// TODO: perform a closer comparison with reference implementations
if constexpr (forward_iterator<_Iter>)
{
auto __next = __first;
*__result = *__next;
while (++__next != __last)
if (!std::__invoke(__comp,
std::__invoke(__proj, *__first),
std::__invoke(__proj, *__next)))
{
__first = __next;
*++__result = *__first;
}
return {__next, std::move(++__result)};
}
else if constexpr (__detail::__can_reread_output<_Out, iter_value_t<_Iter>>)
{
*__result = *__first;
while (++__first != __last)
if (!std::__invoke(__comp,
std::__invoke(__proj, *__result),
std::__invoke(__proj, *__first)))
*++__result = *__first;
return {std::move(__first), std::move(++__result)};
}
else // indirectly_copyable_storable<_Iter, _Out>
{
auto __value = *__first;
*__result = __value;
while (++__first != __last)
{
if (!(bool)std::__invoke(__comp,
std::__invoke(__proj, *__first),
std::__invoke(__proj, __value)))
{
__value = *__first;
*++__result = __value;
}
}
return {std::move(__first), std::move(++__result)};
}
}
template, _Proj>> _Comp = ranges::equal_to>
requires indirectly_copyable, _Out>
&& (forward_iterator>
|| __detail::__can_reread_output<_Out, range_value_t<_Range>>
|| indirectly_copyable_storable, _Out>)
constexpr unique_copy_result, _Out>
operator()(_Range&& __r, _Out __result,
_Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__result),
std::move(__comp), std::move(__proj));
}
};
inline constexpr __unique_copy_fn unique_copy{};
struct __reverse_fn
{
template _Sent>
requires permutable<_Iter>
constexpr _Iter
operator()(_Iter __first, _Sent __last) const
{
auto __i = ranges::next(__first, __last);
auto __tail = __i;
if constexpr (random_access_iterator<_Iter>)
{
if (__first != __last)
{
--__tail;
while (__first < __tail)
{
ranges::iter_swap(__first, __tail);
++__first;
--__tail;
}
}
return __i;
}
else
{
for (;;)
if (__first == __tail || __first == --__tail)
break;
else
{
ranges::iter_swap(__first, __tail);
++__first;
}
return __i;
}
}
template
requires permutable>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r) const
{
return (*this)(ranges::begin(__r), ranges::end(__r));
}
};
inline constexpr __reverse_fn reverse{};
template
using reverse_copy_result = in_out_result<_Iter, _Out>;
struct __reverse_copy_fn
{
template _Sent,
weakly_incrementable _Out>
requires indirectly_copyable<_Iter, _Out>
constexpr reverse_copy_result<_Iter, _Out>
operator()(_Iter __first, _Sent __last, _Out __result) const
{
auto __i = ranges::next(__first, __last);
auto __tail = __i;
while (__first != __tail)
{
--__tail;
*__result = *__tail;
++__result;
}
return {__i, std::move(__result)};
}
template
requires indirectly_copyable, _Out>
constexpr reverse_copy_result, _Out>
operator()(_Range&& __r, _Out __result) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__result));
}
};
inline constexpr __reverse_copy_fn reverse_copy{};
struct __rotate_fn
{
template _Sent>
constexpr subrange<_Iter>
operator()(_Iter __first, _Iter __middle, _Sent __last) const
{
auto __lasti = ranges::next(__first, __last);
if (__first == __middle)
return {__lasti, __lasti};
if (__last == __middle)
return {std::move(__first), std::move(__lasti)};
if constexpr (random_access_iterator<_Iter>)
{
auto __n = __lasti - __first;
auto __k = __middle - __first;
if (__k == __n - __k)
{
ranges::swap_ranges(__first, __middle, __middle, __middle + __k);
return {std::move(__middle), std::move(__lasti)};
}
auto __p = __first;
auto __ret = __first + (__lasti - __middle);
for (;;)
{
if (__k < __n - __k)
{
// TODO: is_pod is deprecated, but this condition is
// consistent with the STL implementation.
if constexpr (__is_pod(iter_value_t<_Iter>))
if (__k == 1)
{
auto __t = std::move(*__p);
ranges::move(__p + 1, __p + __n, __p);
*(__p + __n - 1) = std::move(__t);
return {std::move(__ret), std::move(__lasti)};
}
auto __q = __p + __k;
for (decltype(__n) __i = 0; __i < __n - __k; ++ __i)
{
ranges::iter_swap(__p, __q);
++__p;
++__q;
}
__n %= __k;
if (__n == 0)
return {std::move(__ret), std::move(__lasti)};
ranges::swap(__n, __k);
__k = __n - __k;
}
else
{
__k = __n - __k;
// TODO: is_pod is deprecated, but this condition is
// consistent with the STL implementation.
if constexpr (__is_pod(iter_value_t<_Iter>))
if (__k == 1)
{
auto __t = std::move(*(__p + __n - 1));
ranges::move_backward(__p, __p + __n - 1, __p + __n);
*__p = std::move(__t);
return {std::move(__ret), std::move(__lasti)};
}
auto __q = __p + __n;
__p = __q - __k;
for (decltype(__n) __i = 0; __i < __n - __k; ++ __i)
{
--__p;
--__q;
ranges::iter_swap(__p, __q);
}
__n %= __k;
if (__n == 0)
return {std::move(__ret), std::move(__lasti)};
std::swap(__n, __k);
}
}
}
else if constexpr (bidirectional_iterator<_Iter>)
{
auto __tail = __lasti;
ranges::reverse(__first, __middle);
ranges::reverse(__middle, __tail);
while (__first != __middle && __middle != __tail)
{
ranges::iter_swap(__first, --__tail);
++__first;
}
if (__first == __middle)
{
ranges::reverse(__middle, __tail);
return {std::move(__tail), std::move(__lasti)};
}
else
{
ranges::reverse(__first, __middle);
return {std::move(__first), std::move(__lasti)};
}
}
else
{
auto __first2 = __middle;
do
{
ranges::iter_swap(__first, __first2);
++__first;
++__first2;
if (__first == __middle)
__middle = __first2;
} while (__first2 != __last);
auto __ret = __first;
__first2 = __middle;
while (__first2 != __last)
{
ranges::iter_swap(__first, __first2);
++__first;
++__first2;
if (__first == __middle)
__middle = __first2;
else if (__first2 == __last)
__first2 = __middle;
}
return {std::move(__ret), std::move(__lasti)};
}
}
template
requires permutable>
constexpr borrowed_subrange_t<_Range>
operator()(_Range&& __r, iterator_t<_Range> __middle) const
{
return (*this)(ranges::begin(__r), std::move(__middle),
ranges::end(__r));
}
};
inline constexpr __rotate_fn rotate{};
template
using rotate_copy_result = in_out_result<_Iter, _Out>;
struct __rotate_copy_fn
{
template _Sent,
weakly_incrementable _Out>
requires indirectly_copyable<_Iter, _Out>
constexpr rotate_copy_result<_Iter, _Out>
operator()(_Iter __first, _Iter __middle, _Sent __last,
_Out __result) const
{
auto __copy1 = ranges::copy(__middle,
std::move(__last),
std::move(__result));
auto __copy2 = ranges::copy(std::move(__first),
std::move(__middle),
std::move(__copy1.out));
return { std::move(__copy1.in), std::move(__copy2.out) };
}
template
requires indirectly_copyable, _Out>
constexpr rotate_copy_result, _Out>
operator()(_Range&& __r, iterator_t<_Range> __middle, _Out __result) const
{
return (*this)(ranges::begin(__r), std::move(__middle),
ranges::end(__r), std::move(__result));
}
};
inline constexpr __rotate_copy_fn rotate_copy{};
struct __sample_fn
{
template _Sent,
weakly_incrementable _Out, typename _Gen>
requires (forward_iterator<_Iter> || random_access_iterator<_Out>)
&& indirectly_copyable<_Iter, _Out>
&& uniform_random_bit_generator>
_Out
operator()(_Iter __first, _Sent __last, _Out __out,
iter_difference_t<_Iter> __n, _Gen&& __g) const
{
if constexpr (forward_iterator<_Iter>)
{
// FIXME: Forwarding to std::sample here requires computing __lasti
// which may take linear time.
auto __lasti = ranges::next(__first, __last);
return std::sample(std::move(__first), std::move(__lasti),
std::move(__out), __n, std::forward<_Gen>(__g));
}
else
{
using __distrib_type
= uniform_int_distribution>;
using __param_type = typename __distrib_type::param_type;
__distrib_type __d{};
iter_difference_t<_Iter> __sample_sz = 0;
while (__first != __last && __sample_sz != __n)
{
__out[__sample_sz++] = *__first;
++__first;
}
for (auto __pop_sz = __sample_sz; __first != __last;
++__first, (void) ++__pop_sz)
{
const auto __k = __d(__g, __param_type{0, __pop_sz});
if (__k < __n)
__out[__k] = *__first;
}
return __out + __sample_sz;
}
}
template
requires (forward_range<_Range> || random_access_iterator<_Out>)
&& indirectly_copyable, _Out>
&& uniform_random_bit_generator>
_Out
operator()(_Range&& __r, _Out __out,
range_difference_t<_Range> __n, _Gen&& __g) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__out), __n,
std::forward<_Gen>(__g));
}
};
inline constexpr __sample_fn sample{};
#ifdef _GLIBCXX_USE_C99_STDINT_TR1
struct __shuffle_fn
{
template _Sent,
typename _Gen>
requires permutable<_Iter>
&& uniform_random_bit_generator>
_Iter
operator()(_Iter __first, _Sent __last, _Gen&& __g) const
{
auto __lasti = ranges::next(__first, __last);
std::shuffle(std::move(__first), __lasti, std::forward<_Gen>(__g));
return __lasti;
}
template
requires permutable>
&& uniform_random_bit_generator>
borrowed_iterator_t<_Range>
operator()(_Range&& __r, _Gen&& __g) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::forward<_Gen>(__g));
}
};
inline constexpr __shuffle_fn shuffle{};
#endif
struct __push_heap_fn
{
template _Sent,
typename _Comp = ranges::less, typename _Proj = identity>
requires sortable<_Iter, _Comp, _Proj>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
_Comp __comp = {}, _Proj __proj = {}) const
{
auto __lasti = ranges::next(__first, __last);
std::push_heap(__first, __lasti,
__detail::__make_comp_proj(__comp, __proj));
return __lasti;
}
template
requires sortable, _Comp, _Proj>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__comp), std::move(__proj));
}
};
inline constexpr __push_heap_fn push_heap{};
struct __pop_heap_fn
{
template _Sent,
typename _Comp = ranges::less, typename _Proj = identity>
requires sortable<_Iter, _Comp, _Proj>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
_Comp __comp = {}, _Proj __proj = {}) const
{
auto __lasti = ranges::next(__first, __last);
std::pop_heap(__first, __lasti,
__detail::__make_comp_proj(__comp, __proj));
return __lasti;
}
template
requires sortable, _Comp, _Proj>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__comp), std::move(__proj));
}
};
inline constexpr __pop_heap_fn pop_heap{};
struct __make_heap_fn
{
template _Sent,
typename _Comp = ranges::less, typename _Proj = identity>
requires sortable<_Iter, _Comp, _Proj>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
_Comp __comp = {}, _Proj __proj = {}) const
{
auto __lasti = ranges::next(__first, __last);
std::make_heap(__first, __lasti,
__detail::__make_comp_proj(__comp, __proj));
return __lasti;
}
template
requires sortable, _Comp, _Proj>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__comp), std::move(__proj));
}
};
inline constexpr __make_heap_fn make_heap{};
struct __sort_heap_fn
{
template _Sent,
typename _Comp = ranges::less, typename _Proj = identity>
requires sortable<_Iter, _Comp, _Proj>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
_Comp __comp = {}, _Proj __proj = {}) const
{
auto __lasti = ranges::next(__first, __last);
std::sort_heap(__first, __lasti,
__detail::__make_comp_proj(__comp, __proj));
return __lasti;
}
template
requires sortable, _Comp, _Proj>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__comp), std::move(__proj));
}
};
inline constexpr __sort_heap_fn sort_heap{};
struct __is_heap_until_fn
{
template _Sent,
typename _Proj = identity,
indirect_strict_weak_order>
_Comp = ranges::less>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
_Comp __comp = {}, _Proj __proj = {}) const
{
iter_difference_t<_Iter> __n = ranges::distance(__first, __last);
iter_difference_t<_Iter> __parent = 0, __child = 1;
for (; __child < __n; ++__child)
if (std::__invoke(__comp,
std::__invoke(__proj, *(__first + __parent)),
std::__invoke(__proj, *(__first + __child))))
return __first + __child;
else if ((__child & 1) == 0)
++__parent;
return __first + __n;
}
template, _Proj>>
_Comp = ranges::less>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__comp), std::move(__proj));
}
};
inline constexpr __is_heap_until_fn is_heap_until{};
struct __is_heap_fn
{
template _Sent,
typename _Proj = identity,
indirect_strict_weak_order>
_Comp = ranges::less>
constexpr bool
operator()(_Iter __first, _Sent __last,
_Comp __comp = {}, _Proj __proj = {}) const
{
return (__last
== ranges::is_heap_until(__first, __last,
std::move(__comp),
std::move(__proj)));
}
template, _Proj>>
_Comp = ranges::less>
constexpr bool
operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__comp), std::move(__proj));
}
};
inline constexpr __is_heap_fn is_heap{};
struct __sort_fn
{
template _Sent,
typename _Comp = ranges::less, typename _Proj = identity>
requires sortable<_Iter, _Comp, _Proj>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
_Comp __comp = {}, _Proj __proj = {}) const
{
auto __lasti = ranges::next(__first, __last);
std::sort(std::move(__first), __lasti,
__detail::__make_comp_proj(__comp, __proj));
return __lasti;
}
template
requires sortable, _Comp, _Proj>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__comp), std::move(__proj));
}
};
inline constexpr __sort_fn sort{};
struct __stable_sort_fn
{
template _Sent,
typename _Comp = ranges::less, typename _Proj = identity>
requires sortable<_Iter, _Comp, _Proj>
_Iter
operator()(_Iter __first, _Sent __last,
_Comp __comp = {}, _Proj __proj = {}) const
{
auto __lasti = ranges::next(__first, __last);
std::stable_sort(std::move(__first), __lasti,
__detail::__make_comp_proj(__comp, __proj));
return __lasti;
}
template
requires sortable, _Comp, _Proj>
borrowed_iterator_t<_Range>
operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__comp), std::move(__proj));
}
};
inline constexpr __stable_sort_fn stable_sort{};
struct __partial_sort_fn
{
template _Sent,
typename _Comp = ranges::less, typename _Proj = identity>
requires sortable<_Iter, _Comp, _Proj>
constexpr _Iter
operator()(_Iter __first, _Iter __middle, _Sent __last,
_Comp __comp = {}, _Proj __proj = {}) const
{
if (__first == __middle)
return ranges::next(__first, __last);
ranges::make_heap(__first, __middle, __comp, __proj);
auto __i = __middle;
for (; __i != __last; ++__i)
if (std::__invoke(__comp,
std::__invoke(__proj, *__i),
std::__invoke(__proj, *__first)))
{
ranges::pop_heap(__first, __middle, __comp, __proj);
ranges::iter_swap(__middle-1, __i);
ranges::push_heap(__first, __middle, __comp, __proj);
}
ranges::sort_heap(__first, __middle, __comp, __proj);
return __i;
}
template
requires sortable, _Comp, _Proj>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r, iterator_t<_Range> __middle,
_Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), std::move(__middle),
ranges::end(__r),
std::move(__comp), std::move(__proj));
}
};
inline constexpr __partial_sort_fn partial_sort{};
template
using partial_sort_copy_result = in_out_result<_Iter, _Out>;
struct __partial_sort_copy_fn
{
template _Sent1,
random_access_iterator _Iter2, sentinel_for<_Iter2> _Sent2,
typename _Comp = ranges::less,
typename _Proj1 = identity, typename _Proj2 = identity>
requires indirectly_copyable<_Iter1, _Iter2>
&& sortable<_Iter2, _Comp, _Proj2>
&& indirect_strict_weak_order<_Comp,
projected<_Iter1, _Proj1>,
projected<_Iter2, _Proj2>>
constexpr partial_sort_copy_result<_Iter1, _Iter2>
operator()(_Iter1 __first, _Sent1 __last,
_Iter2 __result_first, _Sent2 __result_last,
_Comp __comp = {},
_Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
{
if (__result_first == __result_last)
{
// TODO: Eliminating the variable __lasti triggers an ICE.
auto __lasti = ranges::next(std::move(__first),
std::move(__last));
return {std::move(__lasti), std::move(__result_first)};
}
auto __result_real_last = __result_first;
while (__first != __last && __result_real_last != __result_last)
{
*__result_real_last = *__first;
++__result_real_last;
++__first;
}
ranges::make_heap(__result_first, __result_real_last, __comp, __proj2);
for (; __first != __last; ++__first)
if (std::__invoke(__comp,
std::__invoke(__proj1, *__first),
std::__invoke(__proj2, *__result_first)))
{
ranges::pop_heap(__result_first, __result_real_last,
__comp, __proj2);
*(__result_real_last-1) = *__first;
ranges::push_heap(__result_first, __result_real_last,
__comp, __proj2);
}
ranges::sort_heap(__result_first, __result_real_last, __comp, __proj2);
return {std::move(__first), std::move(__result_real_last)};
}
template
requires indirectly_copyable, iterator_t<_Range2>>
&& sortable, _Comp, _Proj2>
&& indirect_strict_weak_order<_Comp,
projected, _Proj1>,
projected, _Proj2>>
constexpr partial_sort_copy_result,
borrowed_iterator_t<_Range2>>
operator()(_Range1&& __r, _Range2&& __out, _Comp __comp = {},
_Proj1 __proj1 = {}, _Proj2 __proj2 = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
ranges::begin(__out), ranges::end(__out),
std::move(__comp),
std::move(__proj1), std::move(__proj2));
}
};
inline constexpr __partial_sort_copy_fn partial_sort_copy{};
struct __is_sorted_until_fn
{
template _Sent,
typename _Proj = identity,
indirect_strict_weak_order>
_Comp = ranges::less>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
_Comp __comp = {}, _Proj __proj = {}) const
{
if (__first == __last)
return __first;
auto __next = __first;
for (++__next; __next != __last; __first = __next, (void)++__next)
if (std::__invoke(__comp,
std::__invoke(__proj, *__next),
std::__invoke(__proj, *__first)))
return __next;
return __next;
}
template, _Proj>>
_Comp = ranges::less>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__comp), std::move(__proj));
}
};
inline constexpr __is_sorted_until_fn is_sorted_until{};
struct __is_sorted_fn
{
template _Sent,
typename _Proj = identity,
indirect_strict_weak_order>
_Comp = ranges::less>
constexpr bool
operator()(_Iter __first, _Sent __last,
_Comp __comp = {}, _Proj __proj = {}) const
{
if (__first == __last)
return true;
auto __next = __first;
for (++__next; __next != __last; __first = __next, (void)++__next)
if (std::__invoke(__comp,
std::__invoke(__proj, *__next),
std::__invoke(__proj, *__first)))
return false;
return true;
}
template, _Proj>>
_Comp = ranges::less>
constexpr bool
operator()(_Range&& __r, _Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__comp), std::move(__proj));
}
};
inline constexpr __is_sorted_fn is_sorted{};
struct __nth_element_fn
{
template _Sent,
typename _Comp = ranges::less, typename _Proj = identity>
requires sortable<_Iter, _Comp, _Proj>
constexpr _Iter
operator()(_Iter __first, _Iter __nth, _Sent __last,
_Comp __comp = {}, _Proj __proj = {}) const
{
auto __lasti = ranges::next(__first, __last);
std::nth_element(std::move(__first), std::move(__nth), __lasti,
__detail::__make_comp_proj(__comp, __proj));
return __lasti;
}
template
requires sortable, _Comp, _Proj>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r, iterator_t<_Range> __nth,
_Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), std::move(__nth),
ranges::end(__r), std::move(__comp), std::move(__proj));
}
};
inline constexpr __nth_element_fn nth_element{};
struct __lower_bound_fn
{
template _Sent,
typename _Tp, typename _Proj = identity,
indirect_strict_weak_order>
_Comp = ranges::less>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
const _Tp& __value, _Comp __comp = {}, _Proj __proj = {}) const
{
auto __len = ranges::distance(__first, __last);
while (__len > 0)
{
auto __half = __len / 2;
auto __middle = __first;
ranges::advance(__middle, __half);
if (std::__invoke(__comp, std::__invoke(__proj, *__middle), __value))
{
__first = __middle;
++__first;
__len = __len - __half - 1;
}
else
__len = __half;
}
return __first;
}
template, _Proj>>
_Comp = ranges::less>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r,
const _Tp& __value, _Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
__value, std::move(__comp), std::move(__proj));
}
};
inline constexpr __lower_bound_fn lower_bound{};
struct __upper_bound_fn
{
template _Sent,
typename _Tp, typename _Proj = identity,
indirect_strict_weak_order>
_Comp = ranges::less>
constexpr _Iter
operator()(_Iter __first, _Sent __last,
const _Tp& __value, _Comp __comp = {}, _Proj __proj = {}) const
{
auto __len = ranges::distance(__first, __last);
while (__len > 0)
{
auto __half = __len / 2;
auto __middle = __first;
ranges::advance(__middle, __half);
if (std::__invoke(__comp, __value, std::__invoke(__proj, *__middle)))
__len = __half;
else
{
__first = __middle;
++__first;
__len = __len - __half - 1;
}
}
return __first;
}
template, _Proj>>
_Comp = ranges::less>
constexpr borrowed_iterator_t<_Range>
operator()(_Range&& __r,
const _Tp& __value, _Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
__value, std::move(__comp), std::move(__proj));
}
};
inline constexpr __upper_bound_fn upper_bound{};
struct __equal_range_fn
{
template _Sent,
typename _Tp, typename _Proj = identity,
indirect_strict_weak_order>
_Comp = ranges::less>
constexpr subrange<_Iter>
operator()(_Iter __first, _Sent __last,
const _Tp& __value, _Comp __comp = {}, _Proj __proj = {}) const
{
auto __len = ranges::distance(__first, __last);
while (__len > 0)
{
auto __half = __len / 2;
auto __middle = __first;
ranges::advance(__middle, __half);
if (std::__invoke(__comp,
std::__invoke(__proj, *__middle),
__value))
{
__first = __middle;
++__first;
__len = __len - __half - 1;
}
else if (std::__invoke(__comp,
__value,
std::__invoke(__proj, *__middle)))
__len = __half;
else
{
auto __left
= ranges::lower_bound(__first, __middle,
__value, __comp, __proj);
ranges::advance(__first, __len);
auto __right
= ranges::upper_bound(++__middle, __first,
__value, __comp, __proj);
return {__left, __right};
}
}
return {__first, __first};
}
template, _Proj>>
_Comp = ranges::less>
constexpr borrowed_subrange_t<_Range>
operator()(_Range&& __r, const _Tp& __value,
_Comp __comp = {}, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
__value, std::move(__comp), std::move(__proj));
}
};
inline constexpr __equal_range_fn equal_range{};
struct __binary_search_fn
{
template _Sent,
typename _Tp, typename _Proj = identity,
indirect_strict_weak_order>
_Comp = ranges::less>
constexpr bool
operator()(_Iter __first, _Sent __last,
const _Tp& __value, _Comp __comp = {}, _Proj __proj = {}) const
{
auto __i = ranges::lower_bound(__first, __last, __value, __comp, __proj);
if (__i == __last)
return false;
return !(bool)std::__invoke(__comp, __value,
std::__invoke(__proj, *__i));
}
template, _Proj>>
_Comp = ranges::less>
constexpr bool
operator()(_Range&& __r, const _Tp& __value, _Comp __comp = {},
_Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
__value, std::move(__comp), std::move(__proj));
}
};
inline constexpr __binary_search_fn binary_search{};
struct __is_partitioned_fn
{
template _Sent,
typename _Proj = identity,
indirect_unary_predicate> _Pred>
constexpr bool
operator()(_Iter __first, _Sent __last,
_Pred __pred, _Proj __proj = {}) const
{
__first = ranges::find_if_not(std::move(__first), __last,
__pred, __proj);
if (__first == __last)
return true;
++__first;
return ranges::none_of(std::move(__first), std::move(__last),
std::move(__pred), std::move(__proj));
}
template, _Proj>>
_Pred>
constexpr bool
operator()(_Range&& __r, _Pred __pred, _Proj __proj = {}) const
{
return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__pred), std::move(__proj));
}
};
inline constexpr __is_partitioned_fn is_partitioned{};
struct __partition_fn
{
template _Sent,
typename _Proj = identity,
indirect_unary_predicate> _Pred>
constexpr subrange<_Iter>
operator()(_Iter __first, _Sent __last,
_Pred __pred, _Proj __proj = {}) const
{
if constexpr (bidirectional_iterator<_Iter>)
{
auto __lasti = ranges::next(__first, __last);
auto __tail = __lasti;
for (;;)
{
for (;;)
if (__first == __tail)
return {std::move(__first), std::move(__lasti)};
else if (std::__invoke(__pred,
std::__invoke(__proj, *__first)))
++__first;
else
break;
--__tail;
for (;;)
if (__first == __tail)
return {std::move(__first), std::move(__lasti)};
else if (!(bool)std::__invoke(__pred,
std::__invoke(__proj, *__tail)))
--__tail;
else
break;
ranges::iter_swap(__first, __tail);
++__first;
}
}
else
{
if (__first == __last)
return {__first, __first};
while (std::__invoke(__pred, std::__invoke(__proj, *__first)))
if (++__first == __last)
return {__first, __first};
auto __next = __first;
while (++__next != __last)
if (std::__invoke(__pred, std::__invoke(__proj, *__next)))
{
ranges::iter_swap(__first, __next);
++__first;
}
return {std::move(__first), std::move(__next)};
}
}
template