libcxx/include/__cxx03/__algorithm/max_element.h

   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 <__cxx03/__algorithm/comp.h>
  13 #include <__cxx03/__algorithm/comp_ref_type.h>
  14 #include <__cxx03/__config>
  15 #include <__cxx03/__iterator/iterator_traits.h>
  16
  17 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  18 #  pragma GCC system_header
  19 #endif
  20
  21 _LIBCPP_BEGIN_NAMESPACE_STD
  22
  23 template <class _Compare, class _ForwardIterator>
  24 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
  25 __max_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp) {
  26   static_assert(
  27       __has_forward_iterator_category<_ForwardIterator>::value, "std::max_element requires a ForwardIterator");
  28   if (__first != __last) {
  29     _ForwardIterator __i = __first;
  30     while (++__i != __last)
  31       if (__comp(*__first, *__i))
  32         __first = __i;
  33   }
  34   return __first;
  35 }
  36
  37 template <class _ForwardIterator, class _Compare>
  38 _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
  39 max_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp) {
  40   return std::__max_element<__comp_ref_type<_Compare> >(__first, __last, __comp);
  41 }
  42
  43 template <class _ForwardIterator>
  44 _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
  45 max_element(_ForwardIterator __first, _ForwardIterator __last) {
  46   return std::max_element(__first, __last, __less<>());
  47 }
  48
  49 _LIBCPP_END_NAMESPACE_STD
  50
  51 #endif // _LIBCPP___ALGORITHM_MAX_ELEMENT_H