libstdc++-v3/testsuite/25_algorithms/heap/1.cc

   1 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2009
   2 // Free Software Foundation, Inc.
   3 //
   4 // This file is part of the GNU ISO C++ Library.  This library is free
   5 // software; you can redistribute it and/or modify it under the
   6 // terms of the GNU General Public License as published by the
   7 // Free Software Foundation; either version 3, or (at your option)
   8 // any later version.
   9
  10 // This library is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without Pred the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14
  15 // You should have received a copy of the GNU General Public License along
  16 // with this library; see the file COPYING3.  If not see
  17 // <http://www.gnu.org/licenses/>.
  18
  19 // 25.3.6 Heap operations [lib.alg.heap.operations]
  20
  21 #include <algorithm>
  22 #include <testsuite_hooks.h>
  23
  24 const int A[] = {1, 11, 12, 3, 10, 6, 17, 4, 8, 2, 5, 13, 9, 15, 14, 16, 7};
  25 const int B[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17};
  26 const int C[] = {17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1};
  27 const int N = sizeof(A) / sizeof(int);
  28
  29 // This functor has the equivalent functionality of std::greater<>,
  30 // but there is no dependency on <functional> and it also tracks the
  31 // number of invocations since creation.
  32 class Gt
  33 {
  34 public:
  35   static int count() { return _M_count; }
  36   static void reset() { _M_count = 0; }
  37
  38   bool
  39   operator()(const int& x, const int& y)
  40   {
  41     ++_M_count;
  42     return x > y;
  43   }
  44
  45 private:
  46   static int _M_count;
  47 };
  48
  49 int Gt::_M_count = 0;
  50
  51 // Exercise all of the heap functions for operator<.  The intermediate
  52 // results between push_heap and pop_heap and make_heap and sort_heap
  53 // are not checked (they could be).
  54 void
  55 test01()
  56 {
  57   bool test __attribute__((unused)) = true;
  58
  59   // sort array s1 using push_heap/pop_heap
  60   int s1[N];
  61   std::copy(A, A + N, s1);
  62   VERIFY(std::equal(s1, s1 + N, A));
  63
  64   for (int i = 2; i <= N; ++i)
  65     std::push_heap(s1, s1 + i);
  66
  67   for (int i = N; i >= 2; --i)
  68     std::pop_heap(s1, s1 + i);
  69
  70   VERIFY(std::equal(s1, s1 + N, B));
  71
  72   // sort array s2 using make_heap/sort_heap
  73   int s2[N];
  74   std::copy(A, A + N, s2);
  75   VERIFY(std::equal(s2, s2 + N, A));
  76
  77   std::make_heap(s2, s2 + N);
  78   std::sort_heap(s2, s2 + N);
  79   VERIFY(std::equal(s2, s2 + N, B));
  80 }
  81
  82 // Perform same tests as above but with the comparison predicate
  83 // versions, and add complexity constraint checks.
  84 void
  85 test02()
  86 {
  87   bool test __attribute__((unused)) = true;
  88
  89   Gt gt;
  90
  91 #ifndef _GLIBCXX_DEBUG
  92   //const int logN = static_cast<int>(std::log(static_cast<double>(N)) + 0.5);
  93   const int logN = 3;
  94 #endif
  95
  96   int s1[N];
  97   std::copy(A, A + N, s1);
  98   VERIFY(std::equal(s1, s1 + N, A));
  99
 100   for (int i = 2; i <= N; ++i)
 101     {
 102       std::push_heap(s1, s1 + i, gt);
 103 #ifndef _GLIBCXX_DEBUG
 104       VERIFY(gt.count() <= logN);
 105 #endif
 106       gt.reset();
 107     }
 108
 109   for (int i = N; i >= 2; --i)
 110     {
 111       std::pop_heap(s1, s1 + i, gt);
 112 #ifndef _GLIBCXX_DEBUG
 113       VERIFY(gt.count() <= 2 * logN);
 114 #endif
 115       gt.reset();
 116     }
 117
 118   VERIFY(std::equal(s1, s1 + N, C));
 119
 120   // sort array s2 using make_heap/sort_heap
 121   int s2[N];
 122   std::copy(A, A + N, s2);
 123   VERIFY(std::equal(s2, s2 + N, A));
 124
 125   std::make_heap(s2, s2 + N, gt);
 126 #ifndef _GLIBCXX_DEBUG
 127   VERIFY(gt.count() <= 3 * N);
 128 #endif
 129   gt.reset();
 130
 131   std::sort_heap(s2, s2 + N, gt);
 132 #ifndef _GLIBCXX_DEBUG
 133   VERIFY(gt.count() <= N * logN);
 134 #endif
 135
 136   VERIFY(std::equal(s2, s2 + N, C));
 137 }
 138
 139 int
 140 main()
 141 {
 142   test01();
 143   test02();
 144   return 0;
 145 }