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_PUSH_MACROS
22#include <__undef_macros>
23
24_LIBCPP_BEGIN_NAMESPACE_STD
25
26template <class _InputIterator, class _OutputIterator>
27_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
28partial_sum(_InputIterator __first, _InputIterator __last, _OutputIterator __result) {
29  if (__first != __last) {
30    typename iterator_traits<_InputIterator>::value_type __t(*__first);
31    *__result = __t;
32    for (++__first, (void)++__result; __first != __last; ++__first, (void)++__result) {
33#if _LIBCPP_STD_VER >= 20
34      __t = std::move(__t) + *__first;
35#else
36      __t = __t + *__first;
37#endif
38      *__result = __t;
39    }
40  }
41  return __result;
42}
43
44template <class _InputIterator, class _OutputIterator, class _BinaryOperation>
45_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator
46partial_sum(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _BinaryOperation __binary_op) {
47  if (__first != __last) {
48    typename iterator_traits<_InputIterator>::value_type __t(*__first);
49    *__result = __t;
50    for (++__first, (void)++__result; __first != __last; ++__first, (void)++__result) {
51#if _LIBCPP_STD_VER >= 20
52      __t = __binary_op(std::move(__t), *__first);
53#else
54      __t = __binary_op(__t, *__first);
55#endif
56      *__result = __t;
57    }
58  }
59  return __result;
60}
61
62_LIBCPP_END_NAMESPACE_STD
63
64_LIBCPP_POP_MACROS
65
66#endif // _LIBCPP___NUMERIC_PARTIAL_SUM_H