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1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef _LIBCPP___ALGORITHM_RANGES_MERGE_H10#define _LIBCPP___ALGORITHM_RANGES_MERGE_H11 12#include <__algorithm/in_in_out_result.h>13#include <__algorithm/ranges_copy.h>14#include <__config>15#include <__functional/identity.h>16#include <__functional/invoke.h>17#include <__functional/ranges_operations.h>18#include <__iterator/concepts.h>19#include <__iterator/mergeable.h>20#include <__ranges/access.h>21#include <__ranges/concepts.h>22#include <__ranges/dangling.h>23#include <__type_traits/remove_cvref.h>24#include <__utility/move.h>25 26#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)27# pragma GCC system_header28#endif29 30_LIBCPP_PUSH_MACROS31#include <__undef_macros>32 33#if _LIBCPP_STD_VER >= 2034 35_LIBCPP_BEGIN_NAMESPACE_STD36 37namespace ranges {38 39template <class _InIter1, class _InIter2, class _OutIter>40using merge_result = in_in_out_result<_InIter1, _InIter2, _OutIter>;41 42struct __merge {43 template <input_iterator _InIter1,44 sentinel_for<_InIter1> _Sent1,45 input_iterator _InIter2,46 sentinel_for<_InIter2> _Sent2,47 weakly_incrementable _OutIter,48 class _Comp = less,49 class _Proj1 = identity,50 class _Proj2 = identity>51 requires mergeable<_InIter1, _InIter2, _OutIter, _Comp, _Proj1, _Proj2>52 _LIBCPP_HIDE_FROM_ABI constexpr merge_result<_InIter1, _InIter2, _OutIter> operator()(53 _InIter1 __first1,54 _Sent1 __last1,55 _InIter2 __first2,56 _Sent2 __last2,57 _OutIter __result,58 _Comp __comp = {},59 _Proj1 __proj1 = {},60 _Proj2 __proj2 = {}) const {61 return __merge::__merge_impl(__first1, __last1, __first2, __last2, __result, __comp, __proj1, __proj2);62 }63 64 template <input_range _Range1,65 input_range _Range2,66 weakly_incrementable _OutIter,67 class _Comp = less,68 class _Proj1 = identity,69 class _Proj2 = identity>70 requires mergeable<iterator_t<_Range1>, iterator_t<_Range2>, _OutIter, _Comp, _Proj1, _Proj2>71 _LIBCPP_HIDE_FROM_ABI constexpr merge_result<borrowed_iterator_t<_Range1>, borrowed_iterator_t<_Range2>, _OutIter>72 operator()(_Range1&& __range1,73 _Range2&& __range2,74 _OutIter __result,75 _Comp __comp = {},76 _Proj1 __proj1 = {},77 _Proj2 __proj2 = {}) const {78 return __merge::__merge_impl(79 ranges::begin(__range1),80 ranges::end(__range1),81 ranges::begin(__range2),82 ranges::end(__range2),83 __result,84 __comp,85 __proj1,86 __proj2);87 }88 89 template < class _InIter1,90 class _Sent1,91 class _InIter2,92 class _Sent2,93 class _OutIter,94 class _Comp,95 class _Proj1,96 class _Proj2>97 _LIBCPP_HIDE_FROM_ABI static constexpr merge_result<__remove_cvref_t<_InIter1>,98 __remove_cvref_t<_InIter2>,99 __remove_cvref_t<_OutIter>>100 __merge_impl(_InIter1&& __first1,101 _Sent1&& __last1,102 _InIter2&& __first2,103 _Sent2&& __last2,104 _OutIter&& __result,105 _Comp&& __comp,106 _Proj1&& __proj1,107 _Proj2&& __proj2) {108 for (; __first1 != __last1 && __first2 != __last2; ++__result) {109 if (std::invoke(__comp, std::invoke(__proj2, *__first2), std::invoke(__proj1, *__first1))) {110 *__result = *__first2;111 ++__first2;112 } else {113 *__result = *__first1;114 ++__first1;115 }116 }117 auto __ret1 = ranges::copy(std::move(__first1), std::move(__last1), std::move(__result));118 auto __ret2 = ranges::copy(std::move(__first2), std::move(__last2), std::move(__ret1.out));119 return {std::move(__ret1.in), std::move(__ret2.in), std::move(__ret2.out)};120 }121};122 123inline namespace __cpo {124inline constexpr auto merge = __merge{};125} // namespace __cpo126} // namespace ranges127 128_LIBCPP_END_NAMESPACE_STD129 130#endif // _LIBCPP_STD_VER >= 20131 132_LIBCPP_POP_MACROS133 134#endif // _LIBCPP___ALGORITHM_RANGES_MERGE_H135