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

   1 // Copyright (C) 2001, 2002, 2003, 2004, 2005 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 2, 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 Pred 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 COPYING.  If not, write to the Free
  16 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  17 // USA.
  18
  19 // 25.3.6 Heap operations [lib.alg.heap.operations]
  20
  21 #include <algorithm>
  22 #include <testsuite_hooks.h>
  23
  24 bool test __attribute__((unused)) = true;
  25
  26 const int A[] = {1, 11, 12, 3, 10, 6, 17, 4, 8, 2, 5, 13, 9, 15, 14, 16, 7};
  27 const int B[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17};
  28 const int C[] = {17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1};
  29 const int N = sizeof(A) / sizeof(int);
  30
  31 // This functor has the equivalent functionality of std::greater<>,
  32 // but there is no dependency on <functional> and it also tracks the
  33 // number of invocations since creation.
  34 class Gt
  35 {
  36 public:
  37   static int count() { return itsCount; }
  38   static void reset() { itsCount = 0; }
  39
  40   bool
  41   operator()(const int& x, const int& y)
  42   {
  43     ++itsCount;
  44     return x > y;
  45   }
  46
  47 private:
  48   static int itsCount;
  49 };
  50
  51 int Gt::itsCount = 0;
  52
  53 // Exercise all of the heap functions for operator<.  The
  54 // intermediate results between push_heap and pop_heap and
  55 // make_heap and sort_heap are not checked (they could be).
  56 void
  57 test01()
  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   Gt gt;
  88 //    const int logN = static_cast<int>(std::log(static_cast<double>(N)) + 0.5);
  89   const int logN = 3;
  90
  91   int s1[N];
  92   std::copy(A, A + N, s1);
  93   VERIFY(std::equal(s1, s1 + N, A));
  94
  95   for (int i = 2; i <= N; ++i)
  96     {
  97       std::push_heap(s1, s1 + i, gt);
  98       VERIFY(gt.count() <= logN);
  99       gt.reset();
 100     }
 101
 102   for (int i = N; i >= 2; --i)
 103     {
 104       std::pop_heap(s1, s1 + i, gt);
 105       VERIFY(gt.count() <= 2 * logN);
 106       gt.reset();
 107     }
 108
 109   VERIFY(std::equal(s1, s1 + N, C));
 110
 111   // sort array s2 using make_heap/sort_heap
 112   int s2[N];
 113   std::copy(A, A + N, s2);
 114   VERIFY(std::equal(s2, s2 + N, A));
 115
 116   std::make_heap(s2, s2 + N, gt);
 117   VERIFY(gt.count() <= 3 * N);
 118   gt.reset();
 119
 120   std::sort_heap(s2, s2 + N, gt);
 121   VERIFY(gt.count() <= N * logN);
 122
 123   VERIFY(std::equal(s2, s2 + N, C));
 124 }
 125
 126 int
 127 main()
 128 {
 129   test01();
 130   test02();
 131   return 0;
 132 }