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_EXCLUSIVE_SCAN_H 11 #define _LIBCPP___NUMERIC_EXCLUSIVE_SCAN_H 12 13 #include <__config> 14 #include <__functional/operations.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 #if _LIBCPP_STD_VER >= 17 27 28 template <class _InputIterator, class _OutputIterator, class _Tp, class _BinaryOp> 29 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator 30 exclusive_scan(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _Tp __init, _BinaryOp __b) { 31 if (__first != __last) { 32 _Tp __tmp(__b(__init, *__first)); 33 while (true) { 34 *__result = std::move(__init); 35 ++__result; 36 ++__first; 37 if (__first == __last) 38 break; 39 __init = std::move(__tmp); 40 __tmp = __b(__init, *__first); 41 } 42 } 43 return __result; 44 } 45 46 template <class _InputIterator, class _OutputIterator, class _Tp> 47 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator 48 exclusive_scan(_InputIterator __first, _InputIterator __last, _OutputIterator __result, _Tp __init) { 49 return std::exclusive_scan(__first, __last, __result, __init, std::plus<>()); 50 } 51 52 #endif // _LIBCPP_STD_VER >= 17 53 54 _LIBCPP_END_NAMESPACE_STD 55 56 _LIBCPP_POP_MACROS 57 58 #endif // _LIBCPP___NUMERIC_EXCLUSIVE_SCAN_H 59