libstdc++-v3/testsuite/25_algorithms/binary_search.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 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 COPYING.  If not, write to the Free
  16 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  17 // USA.
  18
  19 // 25.3.3 [lib.alg.binary.search] Binary search algorithms.
  20
  21 #include <algorithm>
  22 #include <testsuite_hooks.h>
  23
  24 bool test __attribute__((unused)) = true;
  25
  26 const int A[] = {1, 2, 3, 3, 3, 5, 8};
  27 const int C[] = {8, 5, 3, 3, 3, 2, 1};
  28 const int N = sizeof(A) / sizeof(int);
  29
  30 // A comparison, equalivalent to std::greater<int> without the
  31 // dependency on <functional>.
  32
  33 struct gt
  34 {
  35     bool
  36     operator()(const int& x, const int& y) const
  37     { return x > y; }
  38 };
  39
  40 // Each test performs general-case, bookend, not-found condition,
  41 // and predicate functional checks.
  42
  43 // 25.3.3.1 lower_bound, with and without comparison predicate
  44 void
  45 test01()
  46 {
  47     using std::lower_bound;
  48
  49     const int first = A[0];
  50     const int last = A[N - 1];
  51
  52     const int* p = lower_bound(A, A + N, 3);
  53     VERIFY(p == A + 2);
  54
  55     const int* q = lower_bound(A, A + N, first);
  56     VERIFY(q == A + 0);
  57
  58     const int* r = lower_bound(A, A + N, last);
  59     VERIFY(r == A + N - 1);
  60
  61     const int* s = lower_bound(A, A + N, 4);
  62     VERIFY(s == A + 5);
  63
  64     const int* t = lower_bound(C, C + N, 3, gt());
  65     VERIFY(t == C + 2);
  66
  67     const int* u = lower_bound(C, C + N, first, gt());
  68     VERIFY(u == C + N - 1);
  69
  70     const int* v = lower_bound(C, C + N, last, gt());
  71     VERIFY(v == C + 0);
  72
  73     const int* w = lower_bound(C, C + N, 4, gt());
  74     VERIFY(w == C + 2);
  75 }
  76
  77 // 25.3.3.2 upper_bound, with and without comparison predicate
  78 void
  79 test02()
  80 {
  81     using std::upper_bound;
  82
  83     const int first = A[0];
  84     const int last = A[N - 1];
  85
  86     const int* p = upper_bound(A, A + N, 3);
  87     VERIFY(p == A + 5);
  88
  89     const int* q = upper_bound(A, A + N, first);
  90     VERIFY(q == A + 1);
  91
  92     const int* r = upper_bound(A, A + N, last);
  93     VERIFY(r == A + N);
  94
  95     const int* s = upper_bound(A, A + N, 4);
  96     VERIFY(s == A + 5);
  97
  98     const int* t = upper_bound(C, C + N, 3, gt());
  99     VERIFY(t == C + 5);
 100
 101     const int* u = upper_bound(C, C + N, first, gt());
 102     VERIFY(u == C + N);
 103
 104     const int* v = upper_bound(C, C + N, last, gt());
 105     VERIFY(v == C + 1);
 106
 107     const int* w = upper_bound(C, C + N, 4, gt());
 108     VERIFY(w == C + 2);
 109 }
 110
 111 // 25.3.3.3 equal_range, with and without comparison predicate
 112 void
 113 test03()
 114 {
 115     using std::equal_range;
 116     typedef std::pair<const int*, const int*> Ipair;
 117
 118     const int first = A[0];
 119     const int last = A[N - 1];
 120
 121     Ipair p = equal_range(A, A + N, 3);
 122     VERIFY(p.first == A + 2);
 123     VERIFY(p.second == A + 5);
 124
 125     Ipair q = equal_range(A, A + N, first);
 126     VERIFY(q.first == A + 0);
 127     VERIFY(q.second == A + 1);
 128
 129     Ipair r = equal_range(A, A + N, last);
 130     VERIFY(r.first == A + N - 1);
 131     VERIFY(r.second == A + N);
 132
 133     Ipair s = equal_range(A, A + N, 4);
 134     VERIFY(s.first == A + 5);
 135     VERIFY(s.second == A + 5);
 136
 137     Ipair t = equal_range(C, C + N, 3, gt());
 138     VERIFY(t.first == C + 2);
 139     VERIFY(t.second == C + 5);
 140
 141     Ipair u = equal_range(C, C + N, first, gt());
 142     VERIFY(u.first == C + N - 1);
 143     VERIFY(u.second == C + N);
 144
 145     Ipair v = equal_range(C, C + N, last, gt());
 146     VERIFY(v.first == C + 0);
 147     VERIFY(v.second == C + 1);
 148
 149     Ipair w = equal_range(C, C + N, 4, gt());
 150     VERIFY(w.first == C + 2);
 151     VERIFY(w.second == C + 2);
 152 }
 153
 154 // 25.3.3.4 binary_search, with and without comparison predicate
 155 void
 156 test04()
 157 {
 158     using std::binary_search;
 159
 160     const int first = A[0];
 161     const int last = A[N - 1];
 162
 163     VERIFY(binary_search(A, A + N, 5));
 164     VERIFY(binary_search(A, A + N, first));
 165     VERIFY(binary_search(A, A + N, last));
 166     VERIFY(!binary_search(A, A + N, 4));
 167
 168     VERIFY(binary_search(C, C + N, 5, gt()));
 169     VERIFY(binary_search(C, C + N, first, gt()));
 170     VERIFY(binary_search(C, C + N, last, gt()));
 171     VERIFY(!binary_search(C, C + N, 4, gt()));
 172 }
 173
 174 int
 175 main()
 176 {
 177   test01();
 178   test02();
 179   test03();
 180   test04();
 181
 182   return 0;
 183 }