BitMagic-C++
sample21.cpp
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1 /*
2 Copyright(c) 2002-2017 Anatoliy Kuznetsov(anatoliy_kuznetsov at yahoo.com)
3 
4 Licensed under the Apache License, Version 2.0 (the "License");
5 you may not use this file except in compliance with the License.
6 You may obtain a copy of the License at
7 
8  http://www.apache.org/licenses/LICENSE-2.0
9 
10 Unless required by applicable law or agreed to in writing, software
11 distributed under the License is distributed on an "AS IS" BASIS,
12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 See the License for the specific language governing permissions and
14 limitations under the License.
15 
16 For more information please visit: http://bitmagic.io
17 */
18 
19 /** \example sample21.cpp
20 
21  Example for shifting - erase of bits.
22 
23  \sa bm::bvector::erase
24  \sa bm::bvector::shift_left
25 */
26 
27 /*! \file sample21.cpp
28  \brief Example: bvector<> - bit-shifts
29 */
30 
31 #include <iostream>
32 
33 #include "bm.h"
34 
35 using namespace std;
36 
37 // Utility template function used to print container
38 template<class T> void PrintContainer(T first, T last)
39 {
40  if (first == last)
41  cout << "<EMPTY SET>";
42  else
43  for(;first != last; ++first)
44  cout << *first << ", ";
45  cout << endl;
46 }
47 
48 int main(void)
49 {
50  try
51  {
52  bm::bvector<> bv { 1, 10, 100 };
53  bv.optimize(); // run memory compression
54 
55  cout << "Source set:";
56  PrintContainer(bv.first(), bv.end());
57 
58  // shift the vector right by 1
59  //
60  bool carry_over = bv.shift_left();
61  cout << "CO=" << carry_over << endl;
62  PrintContainer(bv.first(), bv.end()); // 0, 9, 99
63 
64  // erase 0 bit (equivalent of shift_left)
65  //
66  bv.erase(0);
67  PrintContainer(bv.first(), bv.end()); // 8, 98
68 
69  // erase/insert manipulations with bit-vector may de-optimize
70  // the bit-vector so it needs re-optimization at some point
71  //
72  bv.optimize();
73 
74  }
75  catch(std::exception& ex)
76  {
77  std::cerr << ex.what() << std::endl;
78  return 1;
79  }
80 
81 
82  return 0;
83 }
84 
main
int main(void)
Definition: sample21.cpp:48
bm::bvector<>
bm.h
Compressed bit-vector bvector<> container, set algebraic methods, traversal iterators.
PrintContainer
void PrintContainer(T first, T last)
Definition: sample21.cpp:38
bm::bvector::optimize
void optimize(bm::word_t *temp_block=0, optmode opt_mode=opt_compress, statistics *stat=0)
Optimize memory bitvector's memory allocation.
Definition: bm.h:3097