v1/__numeric/transform_exclusive_scan.h

0001 // -*- C++ -*-
0002 //===----------------------------------------------------------------------===//
0003 //
0004 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0005 // See https://llvm.org/LICENSE.txt for license information.
0006 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0007 //
0008 //===----------------------------------------------------------------------===//
0009
0010 #ifndef _LIBCPP___NUMERIC_TRANSFORM_EXCLUSIVE_SCAN_H
0011 #define _LIBCPP___NUMERIC_TRANSFORM_EXCLUSIVE_SCAN_H
0012
0013 #include <__config>
0014
0015 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
0016 #  pragma GCC system_header
0017 #endif
0018
0019 _LIBCPP_BEGIN_NAMESPACE_STD
0020
0021 #if _LIBCPP_STD_VER >= 17
0022
0023 template <class _InputIterator, class _OutputIterator, class _Tp, class _BinaryOp, class _UnaryOp>
0024 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator transform_exclusive_scan(
0025     _InputIterator __first, _InputIterator __last, _OutputIterator __result, _Tp __init, _BinaryOp __b, _UnaryOp __u) {
0026   if (__first != __last) {
0027     _Tp __saved = __init;
0028     do {
0029       __init    = __b(__init, __u(*__first));
0030       *__result = __saved;
0031       __saved   = __init;
0032       ++__result;
0033     } while (++__first != __last);
0034   }
0035   return __result;
0036 }
0037
0038 #endif // _LIBCPP_STD_VER >= 17
0039
0040 _LIBCPP_END_NAMESPACE_STD
0041
0042 #endif // _LIBCPP___NUMERIC_TRANSFORM_EXCLUSIVE_SCAN_H