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_PARTIAL_SUM_H
11 #define _LIBCPP___NUMERIC_PARTIAL_SUM_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_BEGIN_NAMESPACE_STD
22
23 template <class _InputIterator, class _OutputIterator>
24 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20
25 _OutputIterator
partial_sum(_InputIterator __first,_InputIterator __last,_OutputIterator __result)26 partial_sum(_InputIterator __first, _InputIterator __last, _OutputIterator __result)
27 {
28 if (__first != __last)
29 {
30 typename iterator_traits<_InputIterator>::value_type __t(*__first);
31 *__result = __t;
32 for (++__first, (void) ++__result; __first != __last; ++__first, (void) ++__result)
33 {
34 #if _LIBCPP_STD_VER > 17
35 __t = _VSTD::move(__t) + *__first;
36 #else
37 __t = __t + *__first;
38 #endif
39 *__result = __t;
40 }
41 }
42 return __result;
43 }
44
45 template <class _InputIterator, class _OutputIterator, class _BinaryOperation>
46 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20
47 _OutputIterator
partial_sum(_InputIterator __first,_InputIterator __last,_OutputIterator __result,_BinaryOperation __binary_op)48 partial_sum(_InputIterator __first, _InputIterator __last, _OutputIterator __result,
49 _BinaryOperation __binary_op)
50 {
51 if (__first != __last)
52 {
53 typename iterator_traits<_InputIterator>::value_type __t(*__first);
54 *__result = __t;
55 for (++__first, (void) ++__result; __first != __last; ++__first, (void) ++__result)
56 {
57 #if _LIBCPP_STD_VER > 17
58 __t = __binary_op(_VSTD::move(__t), *__first);
59 #else
60 __t = __binary_op(__t, *__first);
61 #endif
62 *__result = __t;
63 }
64 }
65 return __result;
66 }
67
68 _LIBCPP_END_NAMESPACE_STD
69
70 #endif // _LIBCPP___NUMERIC_PARTIAL_SUM_H
71