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-exception
6//
7//===----------------------------------------------------------------------===//
8
9#ifndef _LIBCPP___ALGORITHM_MAX_ELEMENT_H
10#define _LIBCPP___ALGORITHM_MAX_ELEMENT_H
11
12#include <__algorithm/comp.h>
13#include <__algorithm/comp_ref_type.h>
14#include <__config>
15#include <__iterator/iterator_traits.h>
16#include <__type_traits/is_callable.h>
17
18#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
19# pragma GCC system_header
20#endif
21
22_LIBCPP_BEGIN_NAMESPACE_STD
23
24template <class _Compare, class _ForwardIterator>
25inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
26__max_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp) {
27 static_assert(
28 __has_forward_iterator_category<_ForwardIterator>::value, "std::max_element requires a ForwardIterator");
29 if (__first != __last) {
30 _ForwardIterator __i = __first;
31 while (++__i != __last)
32 if (__comp(*__first, *__i))
33 __first = __i;
34 }
35 return __first;
36}
37
38template <class _ForwardIterator, class _Compare>
39[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
40max_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp) {
41 static_assert(
42 __is_callable<_Compare&, decltype(*__first), decltype(*__first)>::value, "The comparator has to be callable");
43 return std::__max_element<__comp_ref_type<_Compare> >(__first, __last, __comp);
44}
45
46template <class _ForwardIterator>
47[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
48max_element(_ForwardIterator __first, _ForwardIterator __last) {
49 return std::max_element(__first, __last, __less<>());
50}
51
52_LIBCPP_END_NAMESPACE_STD
53
54#endif // _LIBCPP___ALGORITHM_MAX_ELEMENT_H
55