BitMagic-C++
samples
bvsample18
sample18.cpp
Go to the documentation of this file.
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/*
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Copyright(c) 2002-2017 Anatoliy Kuznetsov(anatoliy_kuznetsov at yahoo.com)
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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For more information please visit: http://bitmagic.io
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*/
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/** \example sample18.cpp
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Example of bulk insert iterator
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\sa bm::bvector::insert_iterator
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\sa bm::bvector::bulk_insert_iterator
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*/
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/*! \file sample18.cpp
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\brief Example: bulk insert iterator
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Bulk insert iterator uses internal buffer to accumulate a batch
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of bit indexes and flush it faster.
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This delay makes its behavior different from classic
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deterministic STL iterators.
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*/
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#include <stdlib.h>
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#include <iostream>
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#include "
bm.h
"
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using namespace
std;
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int
main
(
void
)
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{
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try
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{
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bm::bvector<>
bv;
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// use regular insert iterator to add bits to vector
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bm::bvector<>::insert_iterator
iit = bv.
inserter
();
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for
(
unsigned
i = 5; i != 0; --i)
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{
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iit = i;
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cout << bv.
count
() <<
", "
;
// note that bits are added immediately
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}
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cout << endl;
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bv.
clear
();
// clear the vector
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// bulk insert adds bits faster (on sorted data), but provides no guarantee
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// that it happens immediately. Instead it uses an internal buffer to accumulate it first
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// and periodically flushes it into the bit-vector.
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//
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{
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bm::bvector<>::bulk_insert_iterator
bulk_iit(bv);
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for
(
bm::bvector<>::size_type
i = 5; i != 0; --i)
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{
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bulk_iit = i;
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cout << bv.
count
() <<
", "
;
// note that bits are NOT added immediately
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}
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cout << endl;
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}
// <= scope is a point when data flush happens (on destruction)
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cout << bv.
count
() << endl;
// now all bits are added
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bv.
clear
();
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// bulk content flash can be forced, before going out-of-scope
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// which may be problematic due to possible exceptions from the destructor.
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//
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{
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bm::bvector<>::bulk_insert_iterator
bulk_iit(bv);
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for
(
bm::bvector<>::size_type
i = 0; i < 5; ++i)
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bulk_iit = i;
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cout << bv.
count
() << endl;
// not added yet
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bulk_iit.
flush
();
// force bulk iterator to submit the data
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cout << bv.
count
() << endl;
// now added!
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}
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}
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catch
(std::exception& ex)
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{
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std::cerr << ex.what() << std::endl;
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return
1;
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}
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return
0;
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}
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bm::bvector::insert_iterator
Output iterator iterator designed to set "ON" bits based on input sequence of integers (bit indeces).
Definition:
bm.h:377
main
int main(void)
Definition:
sample18.cpp:42
bm::bvector<>
bm::bvector::count
size_type count() const BMNOEXCEPT
population cout (count of ON bits)
Definition:
bm.h:2194
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:3546
bm::bvector::inserter
insert_iterator inserter()
Definition:
bm.h:1245
bm::bvector::bulk_insert_iterator::flush
void flush()
Definition:
bm.h:563
bm::bvector::bulk_insert_iterator
Output iterator iterator designed to set "ON" bits based on input sequence of integers.
Definition:
bm.h:461
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.
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