max_element.h 1.8 KB

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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-exception
  6. //
  7. //===----------------------------------------------------------------------===//
  8. #ifndef _LIBCPP___ALGORITHM_MAX_ELEMENT_H
  9. #define _LIBCPP___ALGORITHM_MAX_ELEMENT_H
  10. #include <__algorithm/comp.h>
  11. #include <__algorithm/comp_ref_type.h>
  12. #include <__config>
  13. #include <__iterator/iterator_traits.h>
  14. #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  15. # pragma GCC system_header
  16. #endif
  17. _LIBCPP_BEGIN_NAMESPACE_STD
  18. template <class _Compare, class _ForwardIterator>
  19. inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
  20. __max_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp) {
  21. static_assert(
  22. __has_forward_iterator_category<_ForwardIterator>::value, "std::max_element requires a ForwardIterator");
  23. if (__first != __last) {
  24. _ForwardIterator __i = __first;
  25. while (++__i != __last)
  26. if (__comp(*__first, *__i))
  27. __first = __i;
  28. }
  29. return __first;
  30. }
  31. template <class _ForwardIterator, class _Compare>
  32. _LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
  33. max_element(_ForwardIterator __first, _ForwardIterator __last, _Compare __comp) {
  34. return std::__max_element<__comp_ref_type<_Compare> >(__first, __last, __comp);
  35. }
  36. template <class _ForwardIterator>
  37. _LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _ForwardIterator
  38. max_element(_ForwardIterator __first, _ForwardIterator __last) {
  39. return std::max_element(__first, __last, __less<>());
  40. }
  41. _LIBCPP_END_NAMESPACE_STD
  42. #endif // _LIBCPP___ALGORITHM_MAX_ELEMENT_H