| //===----------------------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef _LIBCPP___ALGORITHM_LOWER_BOUND_H |
| #define _LIBCPP___ALGORITHM_LOWER_BOUND_H |
| |
| #include <__algorithm/comp.h> |
| #include <__algorithm/half_positive.h> |
| #include <__algorithm/iterator_operations.h> |
| #include <__config> |
| #include <__functional/identity.h> |
| #include <__functional/invoke.h> |
| #include <__iterator/advance.h> |
| #include <__iterator/distance.h> |
| #include <__iterator/iterator_traits.h> |
| #include <__type_traits/is_callable.h> |
| #include <type_traits> |
| |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
| # pragma GCC system_header |
| #endif |
| |
| _LIBCPP_BEGIN_NAMESPACE_STD |
| |
| template <class _IterOps, class _Iter, class _Sent, class _Type, class _Proj, class _Comp> |
| _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17 |
| _Iter __lower_bound_impl(_Iter __first, _Sent __last, const _Type& __value, _Comp& __comp, _Proj& __proj) { |
| auto __len = _IterOps::distance(__first, __last); |
| |
| while (__len != 0) { |
| auto __l2 = std::__half_positive(__len); |
| _Iter __m = __first; |
| _IterOps::advance(__m, __l2); |
| if (std::__invoke(__comp, std::__invoke(__proj, *__m), __value)) { |
| __first = ++__m; |
| __len -= __l2 + 1; |
| } else { |
| __len = __l2; |
| } |
| } |
| return __first; |
| } |
| |
| template <class _ForwardIterator, class _Tp, class _Compare> |
| _LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17 |
| _ForwardIterator lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp) { |
| static_assert(__is_callable<_Compare, decltype(*__first), const _Tp&>::value, |
| "The comparator has to be callable"); |
| auto __proj = std::__identity(); |
| return std::__lower_bound_impl<_StdIterOps>(__first, __last, __value_, __comp, __proj); |
| } |
| |
| template <class _ForwardIterator, class _Tp> |
| _LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17 |
| _ForwardIterator lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_) { |
| return std::lower_bound(__first, __last, __value_, |
| __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>()); |
| } |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| #endif // _LIBCPP___ALGORITHM_LOWER_BOUND_H |