libstdc++-v3/testsuite/25_algorithms/merge/constrained.cc

   1 // Copyright (C) 2020-2025 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 run { target c++20 } }
  19
  20 #include <algorithm>
  21 #include <vector>
  22 #include <testsuite_hooks.h>
  23 #include <testsuite_iterators.h>
  24
  25 using __gnu_test::test_container;
  26 using __gnu_test::test_range;
  27 using __gnu_test::input_iterator_wrapper;
  28 using __gnu_test::output_iterator_wrapper;
  29
  30 namespace ranges = std::ranges;
  31
  32 void
  33 test01()
  34 {
  35   int x[] = {1,2,3,4,5};
  36   for (int i = 0; i <= 5; i++)
  37     for (int j = 0; j <= 5; j++)
  38       {
  39         int z[10];
  40         test_range<int, input_iterator_wrapper> rx(x, x+i), ry(x, x+j);
  41         test_range<int, output_iterator_wrapper> rz(z, z+i+j);
  42         auto [in1,in2,out] = ranges::merge(rx, ry, rz.begin());
  43         VERIFY( in1 == rx.end() );
  44         VERIFY( in2 == ry.end() );
  45         VERIFY( out == rz.end() );
  46
  47         std::vector<int> v(x, x+i);
  48         v.insert(v.end(), x, x+j);
  49         ranges::sort(v);
  50
  51         VERIFY( ranges::equal(v.begin(), v.end(), z, z+i+j) );
  52       }
  53 }
  54
  55 constexpr bool
  56 test02()
  57 {
  58   int x[] = {-1,-3,-5};
  59   int y[] = {2,4,6};
  60   int z[6];
  61   ranges::merge(x, x+3, y, y+3, z,
  62                 ranges::greater{}, {}, [] (int a) { return -a; });
  63
  64   const int w[6] = {-1, 2, -3, 4, -5, 6};
  65   return ranges::equal(w, z);
  66 }
  67
  68
  69 int
  70 main()
  71 {
  72   test01();
  73   static_assert(test02());
  74 }