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

   1 // Copyright (C) 2001 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, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  17 // USA.
  18
  19 // 25.3.6 Heap operations [lib.alg.heap.operations]
  20
  21 #include <algorithm>
  22 //#include <cmath>
  23 #include <testsuite_hooks.h>
  24
  25 bool test = true;
  26
  27 const int A[] = {1, 11, 12, 3, 10, 6, 17, 4, 8, 2, 5, 13, 9, 15, 14, 16, 7};
  28 const int B[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17};
  29 const int C[] = {17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1};
  30 const int N = sizeof(A) / sizeof(int);
  31
  32 // This functor has the equivalent functionality of std::geater<>,
  33 // but there is no dependency on <functional> and it also tracks the
  34 // number of invocations since creation.
  35 class Gt
  36 {
  37 public:
  38     static int count() { return itsCount; }
  39     static void reset() { itsCount = 0; }
  40
  41     bool
  42     operator()(const int& x, const int& y)
  43     {
  44         ++itsCount;
  45         return x > y;
  46     }
  47
  48 private:
  49     static int itsCount;
  50 };
  51
  52 int Gt::itsCount = 0;
  53
  54 // Exercise all of the heap functions for operator<.  The
  55 // intermediate results between push_heap and pop_heap and
  56 // make_heap and sort_heap are not checked (they could be).
  57 void
  58 test01()
  59 {
  60     // sort array s1 using push_heap/pop_heap
  61     int s1[N];
  62     std::copy(A, A + N, s1);
  63     VERIFY(std::equal(s1, s1 + N, A));
  64
  65     for (int i = 2; i <= N; ++i) {
  66         std::push_heap(s1, s1 + i);
  67     }
  68     for (int i = N; i >= 2; --i) {
  69         std::pop_heap(s1, s1 + i);
  70     }
  71     VERIFY(std::equal(s1, s1 + N, B));
  72
  73     // sort array s2 using make_heap/sort_heap
  74     int s2[N];
  75     std::copy(A, A + N, s2);
  76     VERIFY(std::equal(s2, s2 + N, A));
  77
  78     std::make_heap(s2, s2 + N);
  79     std::sort_heap(s2, s2 + N);
  80     VERIFY(std::equal(s2, s2 + N, B));
  81 }
  82
  83 // Perform same tests as above but with the comparison predicate
  84 // versions, and add complexity constraint checks.
  85 void
  86 test02()
  87 {
  88     Gt gt;
  89 //    const int logN = static_cast<int>(std::log(static_cast<double>(N)) + 0.5);
  90     const int logN = 3;
  91
  92     int s1[N];
  93     std::copy(A, A + N, s1);
  94     VERIFY(std::equal(s1, s1 + N, A));
  95
  96     for (int i = 2; i <= N; ++i) {
  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         std::pop_heap(s1, s1 + i, gt);
 104         VERIFY(gt.count() <= 2 * logN);
 105         gt.reset();
 106     }
 107
 108     VERIFY(std::equal(s1, s1 + N, C));
 109
 110     // sort array s2 using make_heap/sort_heap
 111     int s2[N];
 112     std::copy(A, A + N, s2);
 113     VERIFY(std::equal(s2, s2 + N, A));
 114
 115     std::make_heap(s2, s2 + N, gt);
 116     VERIFY(gt.count() <= 3 * N);
 117     gt.reset();
 118
 119     std::sort_heap(s2, s2 + N, gt);
 120     VERIFY(gt.count() <= N * logN);
 121
 122     VERIFY(std::equal(s2, s2 + N, C));
 123 }
 124
 125 int
 126 main(int argc, char* argv[])
 127 {
 128     test01();
 129     test02();
 130
 131     return !test;
 132 }