1 // -*- C++ -*- 2 //===----------------------------------------------------------------------===// 3 // 4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5 // See https://llvm.org/LICENSE.txt for license information. 6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7 // 8 //===----------------------------------------------------------------------===// 9 10 #ifndef _LIBCPP___NUMERIC_ADJACENT_DIFFERENCE_H 11 #define _LIBCPP___NUMERIC_ADJACENT_DIFFERENCE_H 12 13 #include <__config> 14 #include <__iterator/iterator_traits.h> 15 #include <__utility/move.h> 16 17 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 18 # pragma GCC system_header 19 #endif 20 21 _LIBCPP_PUSH_MACROS 22 #include <__undef_macros> 23 24 _LIBCPP_BEGIN_NAMESPACE_STD 25 26 template <class _InputIterator, class _OutputIterator> 27 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 28 _OutputIterator 29 adjacent_difference(_InputIterator __first, _InputIterator __last, _OutputIterator __result) 30 { 31 if (__first != __last) 32 { 33 typename iterator_traits<_InputIterator>::value_type __acc(*__first); 34 *__result = __acc; 35 for (++__first, (void) ++__result; __first != __last; ++__first, (void) ++__result) 36 { 37 typename iterator_traits<_InputIterator>::value_type __val(*__first); 38 #if _LIBCPP_STD_VER >= 20 39 *__result = __val - _VSTD::move(__acc); 40 #else 41 *__result = __val - __acc; 42 #endif 43 __acc = _VSTD::move(__val); 44 } 45 } 46 return __result; 47 } 48 49 template <class _InputIterator, class _OutputIterator, class _BinaryOperation> 50 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 51 _OutputIterator 52 adjacent_difference(_InputIterator __first, _InputIterator __last, _OutputIterator __result, 53 _BinaryOperation __binary_op) 54 { 55 if (__first != __last) 56 { 57 typename iterator_traits<_InputIterator>::value_type __acc(*__first); 58 *__result = __acc; 59 for (++__first, (void) ++__result; __first != __last; ++__first, (void) ++__result) 60 { 61 typename iterator_traits<_InputIterator>::value_type __val(*__first); 62 #if _LIBCPP_STD_VER >= 20 63 *__result = __binary_op(__val, _VSTD::move(__acc)); 64 #else 65 *__result = __binary_op(__val, __acc); 66 #endif 67 __acc = _VSTD::move(__val); 68 } 69 } 70 return __result; 71 } 72 73 _LIBCPP_END_NAMESPACE_STD 74 75 _LIBCPP_POP_MACROS 76 77 #endif // _LIBCPP___NUMERIC_ADJACENT_DIFFERENCE_H 78