libstdc++-v3/testsuite/26_numerics/inner_product/constexpr.cc

   1 // Copyright (C) 2020-2024 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-do compile { target c++20 } }
  19
  20 #include <functional>
  21 #include <numeric>
  22
  23 constexpr bool
  24 test01()
  25 {
  26   int x[5] = {1,2,3,4,5};
  27   int y[5] = {2,4,6,8,10};
  28   auto ret = std::inner_product(x, x+5, y, 0);
  29   return ret == 110;
  30 }
  31
  32 static_assert(test01());
  33
  34 constexpr bool
  35 test02()
  36 {
  37   int x[5] = {1,2,3,4,5};
  38   int y[5] = {2,4,6,8,10};
  39   auto ret = std::inner_product(x, x+5, y, 1,
  40                                 std::multiplies{}, std::plus{});
  41   return ret == 3*6*9*12*15;
  42 }
  43
  44 static_assert(test02());