libstdc++-v3/testsuite/25_algorithms/lower_bound/2.cc

   1 // Copyright (C) 2001-2013 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 // 25.3.3 [lib.alg.binary.search] Binary search algorithms.
  19
  20 #include <algorithm>
  21 #include <testsuite_hooks.h>
  22
  23 bool test __attribute__((unused)) = true;
  24
  25 const int A[] = {1, 2, 3, 3, 3, 5, 8};
  26 const int C[] = {8, 5, 3, 3, 3, 2, 1};
  27 const int N = sizeof(A) / sizeof(int);
  28
  29 // A comparison, equalivalent to std::greater<int> without the
  30 // dependency on <functional>.
  31 struct gt
  32 {
  33     bool
  34     operator()(const int& x, const int& y) const
  35     { return x > y; }
  36 };
  37
  38 // Each test performs general-case, bookend, not-found condition,
  39 // and predicate functional checks.
  40
  41 // 25.3.3.1 lower_bound, with and without comparison predicate
  42 void
  43 test01()
  44 {
  45     using std::lower_bound;
  46
  47     const int first = A[0];
  48     const int last = A[N - 1];
  49
  50     const int* p = lower_bound(A, A + N, 3);
  51     VERIFY(p == A + 2);
  52
  53     const int* q = lower_bound(A, A + N, first);
  54     VERIFY(q == A + 0);
  55
  56     const int* r = lower_bound(A, A + N, last);
  57     VERIFY(r == A + N - 1);
  58
  59     const int* s = lower_bound(A, A + N, 4);
  60     VERIFY(s == A + 5);
  61
  62     const int* t = lower_bound(C, C + N, 3, gt());
  63     VERIFY(t == C + 2);
  64
  65     const int* u = lower_bound(C, C + N, first, gt());
  66     VERIFY(u == C + N - 1);
  67
  68     const int* v = lower_bound(C, C + N, last, gt());
  69     VERIFY(v == C + 0);
  70
  71     const int* w = lower_bound(C, C + N, 4, gt());
  72     VERIFY(w == C + 2);
  73 }
  74
  75 int
  76 main()
  77 {
  78   test01();
  79   return 0;
  80 }