xref: /llvm-project/libcxx/include/__cxx03/__algorithm/upper_bound.h (revision ce7771902dc50d900de639d499a60486b83f70e0)
1e78f53d1SNikolas Klauser //===----------------------------------------------------------------------===//
2e78f53d1SNikolas Klauser //
3e78f53d1SNikolas Klauser // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4e78f53d1SNikolas Klauser // See https://llvm.org/LICENSE.txt for license information.
5e78f53d1SNikolas Klauser // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6e78f53d1SNikolas Klauser //
7e78f53d1SNikolas Klauser //===----------------------------------------------------------------------===//
8e78f53d1SNikolas Klauser 
9*ce777190SNikolas Klauser #ifndef _LIBCPP___CXX03___ALGORITHM_UPPER_BOUND_H
10*ce777190SNikolas Klauser #define _LIBCPP___CXX03___ALGORITHM_UPPER_BOUND_H
11e78f53d1SNikolas Klauser 
1273fbae83SNikolas Klauser #include <__cxx03/__algorithm/comp.h>
1373fbae83SNikolas Klauser #include <__cxx03/__algorithm/half_positive.h>
1473fbae83SNikolas Klauser #include <__cxx03/__algorithm/iterator_operations.h>
1573fbae83SNikolas Klauser #include <__cxx03/__config>
1673fbae83SNikolas Klauser #include <__cxx03/__functional/identity.h>
1773fbae83SNikolas Klauser #include <__cxx03/__functional/invoke.h>
1873fbae83SNikolas Klauser #include <__cxx03/__iterator/advance.h>
1973fbae83SNikolas Klauser #include <__cxx03/__iterator/distance.h>
2073fbae83SNikolas Klauser #include <__cxx03/__iterator/iterator_traits.h>
2173fbae83SNikolas Klauser #include <__cxx03/__type_traits/is_constructible.h>
2273fbae83SNikolas Klauser #include <__cxx03/__utility/move.h>
23e78f53d1SNikolas Klauser 
24e78f53d1SNikolas Klauser #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
25e78f53d1SNikolas Klauser #  pragma GCC system_header
26e78f53d1SNikolas Klauser #endif
27e78f53d1SNikolas Klauser 
28e78f53d1SNikolas Klauser _LIBCPP_PUSH_MACROS
2973fbae83SNikolas Klauser #include <__cxx03/__undef_macros>
30e78f53d1SNikolas Klauser 
31e78f53d1SNikolas Klauser _LIBCPP_BEGIN_NAMESPACE_STD
32e78f53d1SNikolas Klauser 
33e78f53d1SNikolas Klauser template <class _AlgPolicy, class _Compare, class _Iter, class _Sent, class _Tp, class _Proj>
34e78f53d1SNikolas Klauser _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Iter
35e78f53d1SNikolas Klauser __upper_bound(_Iter __first, _Sent __last, const _Tp& __value, _Compare&& __comp, _Proj&& __proj) {
36e78f53d1SNikolas Klauser   auto __len = _IterOps<_AlgPolicy>::distance(__first, __last);
37e78f53d1SNikolas Klauser   while (__len != 0) {
38e78f53d1SNikolas Klauser     auto __half_len = std::__half_positive(__len);
39e78f53d1SNikolas Klauser     auto __mid      = _IterOps<_AlgPolicy>::next(__first, __half_len);
40e78f53d1SNikolas Klauser     if (std::__invoke(__comp, __value, std::__invoke(__proj, *__mid)))
41e78f53d1SNikolas Klauser       __len = __half_len;
42e78f53d1SNikolas Klauser     else {
43e78f53d1SNikolas Klauser       __first = ++__mid;
44e78f53d1SNikolas Klauser       __len -= __half_len + 1;
45e78f53d1SNikolas Klauser     }
46e78f53d1SNikolas Klauser   }
47e78f53d1SNikolas Klauser   return __first;
48e78f53d1SNikolas Klauser }
49e78f53d1SNikolas Klauser 
50e78f53d1SNikolas Klauser template <class _ForwardIterator, class _Tp, class _Compare>
51e78f53d1SNikolas Klauser _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
52e78f53d1SNikolas Klauser upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value, _Compare __comp) {
53e78f53d1SNikolas Klauser   static_assert(is_copy_constructible<_ForwardIterator>::value, "Iterator has to be copy constructible");
54e78f53d1SNikolas Klauser   return std::__upper_bound<_ClassicAlgPolicy>(
55e78f53d1SNikolas Klauser       std::move(__first), std::move(__last), __value, std::move(__comp), std::__identity());
56e78f53d1SNikolas Klauser }
57e78f53d1SNikolas Klauser 
58e78f53d1SNikolas Klauser template <class _ForwardIterator, class _Tp>
59e78f53d1SNikolas Klauser _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
60e78f53d1SNikolas Klauser upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
61e78f53d1SNikolas Klauser   return std::upper_bound(std::move(__first), std::move(__last), __value, __less<>());
62e78f53d1SNikolas Klauser }
63e78f53d1SNikolas Klauser 
64e78f53d1SNikolas Klauser _LIBCPP_END_NAMESPACE_STD
65e78f53d1SNikolas Klauser 
66e78f53d1SNikolas Klauser _LIBCPP_POP_MACROS
67e78f53d1SNikolas Klauser 
68*ce777190SNikolas Klauser #endif // _LIBCPP___CXX03___ALGORITHM_UPPER_BOUND_H
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