BitMagic-C++
sample7.cpp

Example how to use logical operations between arrays and bit-vectors

See also
bm::combine_and
bm::combine_and_sorted
bm::combine_sub
bm::combine_or
bm::combine_xor
bvsetalgebra.cpp
/*
Copyright(c) 2002-2017 Anatoliy Kuznetsov(anatoliy_kuznetsov at yahoo.com)
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
For more information please visit: http://bitmagic.io
*/
/** \example sample7.cpp
Example how to use logical operations between arrays and bit-vectors
\sa bm::combine_and
\sa bm::combine_and_sorted
\sa bm::combine_sub
\sa bm::combine_or
\sa bm::combine_xor
\sa bvsetalgebra.cpp
*/
/*! \file sample7.cpp
\brief Example: set operations between bvector<> and arrays of integers.
*/
#include <iostream>
#include <algorithm>
#include <vector>
#include <list>
using std::vector;
using std::list;
// This example requires STL compatibility
#ifdef BM_NO_STL
# undef BM_NO_STL
#endif
#include "bm.h"
#include "bmalgo.h"
using namespace std;
inline
void Print(unsigned n)
{
cout << n << endl;;
}
// Utility template function used to print container
template<class T> void PrintContainer(T first, T last)
{
if (first == last)
cout << "<EMPTY SET>";
else
for(;first != last; ++first)
cout << *first << ";";
cout << endl;
}
int main(void)
{
try
{
bv[10] = true;
bv[100] = true;
bv[10000] = true;
// initialize unsorted, fairly random array for an experiment
// it even allowes duplicates (see 12)
//
bm::bvector<>::size_type arr[] = {2, 10000, 5, 12, 255, 12, 300};
cout << "Source set 1:";
PrintContainer(bv.first(), bv.end());
cout << "Source set 2:";
PrintContainer(&arr[0], &arr[0] + (sizeof(arr)/sizeof(arr[0])));
// AND operation between bit-vector and a plain array
// expect one result: 10000
// please note, that array in this case comes unsorted
//
bm::combine_and(bv, &arr[0], &arr[0] + (sizeof(arr)/sizeof(arr[0])));
cout << "Result 1(AND): ";
PrintContainer(bv.first(), bv.end());
// re-initalize the bit-vector
bv.clear();
bv[10] = true;
bv[100] = true;
bv[10000] = true;
// OR operation to merge bit-vector and array
// please note that it naturally works as sort-unique for the array
//
bm::combine_or(bv, &arr[0], &arr[0] + (sizeof(arr)/sizeof(arr[0])));
cout << "Result 2(OR): ";
PrintContainer(bv.first(), bv.end());
// sort the array, using STL sort method
// combine operation on sorted arrays tend to be faster
//
std::sort(&arr[0], &arr[0] + (sizeof(arr)/sizeof(arr[0])));
// AND on sorted array is faster
//
bm::combine_and_sorted(bv, &arr[0], &arr[0] + (sizeof(arr)/sizeof(arr[0])));
cout << "Result 3(AND): ";
PrintContainer(bv.first(), bv.end());
// SUB (AND NOT or MINUS) also works faster on sorted input
// the result should be an EMPTY set
bm::combine_sub(bv, &arr[0], &arr[0] + (sizeof(arr)/sizeof(arr[0])));
cout << "Result 4(MINUS): ";
PrintContainer(bv.first(), bv.end());
}
catch(std::exception& ex)
{
std::cerr << ex.what() << std::endl;
return 1;
}
return 0;
}
bm::combine_and
void combine_and(BV &bv, It first, It last)
AND Combine bitvector and the iterable sequence.
Definition: bmalgo_impl.h:1301
Print
void Print(unsigned n)
Definition: sample7.cpp:55
bmalgo.h
Algorithms for bvector<> (main include)
PrintContainer
void PrintContainer(T first, T last)
Definition: sample7.cpp:61
bm::bvector<>
bm::combine_and_sorted
void combine_and_sorted(BV &bv, It first, It last)
AND Combine bitvector and the iterable sequence.
Definition: bmalgo_impl.h:1269
bm::bvector::clear
void clear(const size_type *ids, size_type ids_size, bm::sort_order so=bm::BM_UNKNOWN)
clear list of bits in this bitset
Definition: bm.h:3560
bm::combine_or
void combine_or(BV &bv, It first, It last)
OR Combine bitvector and the iterable sequence.
Definition: bmalgo_impl.h:1016
bm::bvector::end
enumerator end() const
Returns enumerator pointing on the next bit after the last.
Definition: bm.h:1790
main
int main(void)
Definition: sample7.cpp:71
bm::bvector::first
enumerator first() const
Returns enumerator pointing on the first non-zero bit.
Definition: bm.h:1784
bm::bvector::size_type
bm::id_t size_type
Definition: bm.h:117
bm.h
Compressed bit-vector bvector<> container, set algebraic methods, traversal iterators.
bm::combine_sub
void combine_sub(BV &bv, It first, It last)
SUB Combine bitvector and the iterable sequence.
Definition: bmalgo_impl.h:1184