sample18a.cpp
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/*
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 sample18a.cpp
Example of bit-vector import from an external bit-stream
\sa bm::bvector::bulk_insert_iterator
*/
/*! \file sample18a.cpp
\brief Example: import from an external bit-stream
*/
#include <stdlib.h>
#include <assert.h>
#include <iostream>
#include "bm.h"
#include "bmbvimport.h"
#include "bmundef.h" /* clear the pre-proc defines from BM */
using namespace std;
int main(void)
{
try
{
bm::bvector<> bv;
// specify bits in an array of unsigned ints (32-bit)
// we expect that each set bit can be efficiently imported into a
// bvector<>. Import function breaks the bit stream into blocks,
// each block can be optimized/compressed on the fly, while data is
// still in the CPU cache
unsigned int arr[2058] = {0, };
arr[0] = 1 << 16;
arr[2047] = 1u << 31;
arr[2048] = 1u << 7;
bm::bit_import_u32(bv, arr, sizeof(arr)/sizeof(arr[0]), true/* optimize on the fly*/);
auto cnt = bv.count();
cout << "Imported " << cnt << " bits." << endl;
assert(cnt == 3);
assert(bv.test(16));
assert(bv.test(65535));
assert(bv.test(65536 + 7));
}
catch(std::exception& ex)
{
std::cerr << ex.what() << std::endl;
return 1;
}
return 0;
}
bm.h
Compressed bit-vector bvector<> container, set algebraic methods, traversal iterators.
bmbvimport.h
Import of bvector<> from native type bit-arrays.
bmundef.h
pre-processor un-defines to avoid global space pollution (internal)
bm::bvector
Bitvector Bit-vector container with runtime compression of bits.
Definition bm.h:115
bm::bvector::test
bool test(size_type n) const BMNOEXCEPT
returns true if bit n is set and false is bit n is 0.
Definition bm.h:1502
bm::bvector::count
size_type count() const BMNOEXCEPT
population count (count of ON bits)
Definition bm.h:2401
bm::bit_import_u32
void bit_import_u32(BV &bv, const unsigned int *BMRESTRICT bit_arr, typename BV::size_type bit_arr_size, bool optimize)
Import native stream of bits (represented as 32-bit unsigned ints).
Definition bmbvimport.h:46
main
int main(void)
Definition sample18a.cpp:38