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

   1 // Copyright (C) 2001-2016 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 const int A[] = {1, 2, 3, 3, 3, 5, 8};
  24 const int C[] = {8, 5, 3, 3, 3, 2, 1};
  25 const int N = sizeof(A) / sizeof(int);
  26
  27 // A comparison, equalivalent to std::greater<int> without the
  28 // dependency on <functional>.
  29 struct gt
  30 {
  31     bool
  32     operator()(const int& x, const int& y) const
  33     { return x > y; }
  34 };
  35
  36 // Each test performs general-case, bookend, not-found condition,
  37 // and predicate functional checks.
  38
  39 // 25.3.3.1 lower_bound, with and without comparison predicate
  40 void
  41 test01()
  42 {
  43     using std::lower_bound;
  44
  45     const int first = A[0];
  46     const int last = A[N - 1];
  47
  48     const int* p = lower_bound(A, A + N, 3);
  49     VERIFY(p == A + 2);
  50
  51     const int* q = lower_bound(A, A + N, first);
  52     VERIFY(q == A + 0);
  53
  54     const int* r = lower_bound(A, A + N, last);
  55     VERIFY(r == A + N - 1);
  56
  57     const int* s = lower_bound(A, A + N, 4);
  58     VERIFY(s == A + 5);
  59
  60     const int* t = lower_bound(C, C + N, 3, gt());
  61     VERIFY(t == C + 2);
  62
  63     const int* u = lower_bound(C, C + N, first, gt());
  64     VERIFY(u == C + N - 1);
  65
  66     const int* v = lower_bound(C, C + N, last, gt());
  67     VERIFY(v == C + 0);
  68
  69     const int* w = lower_bound(C, C + N, 4, gt());
  70     VERIFY(w == C + 2);
  71 }
  72
  73 int
  74 main()
  75 {
  76   test01();
  77   return 0;
  78 }