libstdc++-v3/testsuite/23_containers/bitset/operations/1.cc

   1 // 2000-01-15  Anders Widell  <awl@hem.passagen.se>
   2
   3 // Copyright (C) 2000-2020 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20 #include <string>
  21 #include <set>
  22 #include <bitset>
  23 #include <testsuite_hooks.h>
  24
  25 static char original_bits[1024];
  26 static char left_shifted[1024];
  27 static char right_shifted[1024];
  28
  29 char
  30 random_bit() {
  31   static long x = 1;
  32   return ((x = (3432L*x + 6789L) % 9973L) & 1) + '0';
  33 }
  34
  35 void
  36 initialise(size_t size) {
  37   for (size_t i=0; i<size; i++)
  38     original_bits[i] = random_bit();
  39
  40   original_bits[size] = '\0';
  41   left_shifted[size] = '\0';
  42   right_shifted[size] = '\0';
  43 }
  44
  45 void
  46 shift_arrays(size_t shift_step, size_t size) {
  47   for (size_t i=shift_step; i<size; i++) {
  48     right_shifted[i] = original_bits[i-shift_step];
  49     left_shifted[size-i-1] = original_bits[size+shift_step-i-1];
  50   }
  51   for (size_t i=0; i<shift_step && i<size; i++) {
  52     right_shifted[i] = '0';
  53     left_shifted[size-i-1] = '0';
  54   }
  55 }
  56
  57 template <size_t size>
  58   bool
  59   do_test()
  60   {
  61     bool test = true;
  62
  63     std::bitset<size> shifted;
  64     std::bitset<size> correct;
  65
  66     initialise(size);
  67
  68     //std::bitset<size> original = std::string(original_bits);
  69     std::bitset<size> original = std::bitset<size> (std::string(original_bits));
  70
  71     for (size_t shift_step=0; shift_step==0 || shift_step<size; shift_step++) {
  72       shift_arrays(shift_step, size);
  73
  74       shifted = original;
  75       shifted <<= shift_step;
  76       //correct = std::string(left_shifted);
  77       correct = std::bitset<size> (std::string(left_shifted));
  78       VERIFY( shifted == correct );
  79
  80       shifted = original;
  81       shifted >>= shift_step;
  82       //correct = std::string(right_shifted);
  83       correct = std::bitset<size> (std::string(right_shifted));
  84       VERIFY( shifted == correct );
  85     }
  86
  87     return test;
  88   }
  89
  90 void
  91 test01() {
  92   VERIFY( do_test<32>() );
  93   VERIFY( do_test<48>() );
  94   VERIFY( do_test<64>() );
  95
  96   VERIFY( do_test<511>() );
  97   VERIFY( do_test<513>() );
  98   VERIFY( do_test<997>() );
  99 }
 100
 101 int
 102 main()
 103 {
 104   test01();
 105   return 0;
 106 }