libcxx/include/__numeric/inner_product.h

   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_INNER_PRODUCT_H
  11 #define _LIBCPP___NUMERIC_INNER_PRODUCT_H
  12
  13 #include <__config>
  14 #include <__utility/move.h>
  15
  16 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  17 #  pragma GCC system_header
  18 #endif
  19
  20 _LIBCPP_PUSH_MACROS
  21 #include <__undef_macros>
  22
  23 _LIBCPP_BEGIN_NAMESPACE_STD
  24
  25 template <class _InputIterator1, class _InputIterator2, class _Tp>
  26 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp
  27 inner_product(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _Tp __init) {
  28   for (; __first1 != __last1; ++__first1, (void)++__first2)
  29 #if _LIBCPP_STD_VER >= 20
  30     __init = std::move(__init) + *__first1 * *__first2;
  31 #else
  32     __init = __init + *__first1 * *__first2;
  33 #endif
  34   return __init;
  35 }
  36
  37 template <class _InputIterator1, class _InputIterator2, class _Tp, class _BinaryOperation1, class _BinaryOperation2>
  38 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp inner_product(
  39     _InputIterator1 __first1,
  40     _InputIterator1 __last1,
  41     _InputIterator2 __first2,
  42     _Tp __init,
  43     _BinaryOperation1 __binary_op1,
  44     _BinaryOperation2 __binary_op2) {
  45   for (; __first1 != __last1; ++__first1, (void)++__first2)
  46 #if _LIBCPP_STD_VER >= 20
  47     __init = __binary_op1(std::move(__init), __binary_op2(*__first1, *__first2));
  48 #else
  49     __init = __binary_op1(__init, __binary_op2(*__first1, *__first2));
  50 #endif
  51   return __init;
  52 }
  53
  54 _LIBCPP_END_NAMESPACE_STD
  55
  56 _LIBCPP_POP_MACROS
  57
  58 #endif // _LIBCPP___NUMERIC_INNER_PRODUCT_H