libstdc++-v3/testsuite/performance/25_algorithms/sort_heap.cc

   1 // Copyright (C) 2013-2020 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 #include <vector>
  19 #include <algorithm>
  20 #include <testsuite_performance.h>
  21
  22 int main()
  23 {
  24   using namespace __gnu_test;
  25
  26   time_counter time;
  27   resource_counter resource;
  28
  29   const int max_size = 10000000;
  30
  31   std::vector<int> v(max_size);
  32
  33   for (int i = 0; i < max_size; ++i)
  34     v[i] = -i;
  35
  36   start_counters(time, resource);
  37   std::make_heap(v.begin(), v.end());
  38   stop_counters(time, resource);
  39
  40   report_performance(__FILE__, "make_heap_reverse", time, resource);
  41   clear_counters(time, resource);
  42
  43   for (int i = 0; i < max_size; ++i)
  44     v[i] = i;
  45
  46   start_counters(time, resource);
  47   std::make_heap(v.begin(), v.end());
  48   stop_counters(time, resource);
  49
  50   report_performance(__FILE__, "make_heap_forwards", time, resource);
  51   clear_counters(time, resource);
  52
  53   // a simple psuedo-random series which does not rely on rand() and friends
  54   v[0] = 0;
  55   for (int i = 1; i < max_size; ++i)
  56     v[i] = (v[i-1] + 110211473) * 745988807;
  57
  58   start_counters(time, resource);
  59   std::make_heap(v.begin(), v.end());
  60   stop_counters(time, resource);
  61
  62   report_performance(__FILE__, "make_heap_random", time, resource);
  63
  64
  65   start_counters(time, resource);
  66   std::sort_heap(v.begin(), v.end());
  67   stop_counters(time, resource);
  68
  69   report_performance(__FILE__, "sort_heap", time, resource);
  70   clear_counters(time, resource);
  71
  72   return 0;
  73 }