llvm-project/libcxx/include/__numeric/adjacent_difference.h

73 lines
2.3 KiB
C++

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// 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___NUMERIC_ADJACENT_DIFFERENCE_H
#define _LIBCPP___NUMERIC_ADJACENT_DIFFERENCE_H
#include <__config>
#include <__iterator/iterator_traits.h>
#include <__utility/move.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
template <class _InputIterator, class _OutputIterator>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
_OutputIterator
adjacent_difference(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
{
if (__first != __last)
{
typename iterator_traits<_InputIterator>::value_type __acc(*__first);
*__result = __acc;
for (++__first, (void) ++__result; __first != __last; ++__first, (void) ++__result)
{
typename iterator_traits<_InputIterator>::value_type __val(*__first);
#if _LIBCPP_STD_VER > 17
*__result = __val - _VSTD::move(__acc);
#else
*__result = __val - __acc;
#endif
__acc = _VSTD::move(__val);
}
}
return __result;
}
template <class _InputIterator, class _OutputIterator, class _BinaryOperation>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
_OutputIterator
adjacent_difference(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
_BinaryOperation __binary_op)
{
if (__first != __last)
{
typename iterator_traits<_InputIterator>::value_type __acc(*__first);
*__result = __acc;
for (++__first, (void) ++__result; __first != __last; ++__first, (void) ++__result)
{
typename iterator_traits<_InputIterator>::value_type __val(*__first);
#if _LIBCPP_STD_VER > 17
*__result = __binary_op(__val, _VSTD::move(__acc));
#else
*__result = __binary_op(__val, __acc);
#endif
__acc = _VSTD::move(__val);
}
}
return __result;
}
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___NUMERIC_ADJACENT_DIFFERENCE_H