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실행결과)

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소스)

#include "stdafx.h"

#include <boost/utility.hpp>

#include <boost/pool/object_pool.hpp>

using namespace std;

using namespace boost;

// memory

// 1000 0000

// 1000 0000

// 0: first bit

// 0000 0001

// 7: last bit

class BitSet

{

public:

typedef vector<char> Buffer;

Buffer _buffer;

int _bitCount;

void resize(int bitCount)

{

int byteCount= (int)(ceil((float)bitCount/8));

_bitCount=bitCount;

_buffer.resize(byteCount);

memset(&_buffer.front(), 0,  byteCount);

}

BitSet()

{

}

~BitSet()

{

}

void setBit(int id, bool on)

{

ASSERT(0<=id && id< _bitCount);

ASSERT(0<_buffer.size());

int whichByte= id/ 8;

int whichBit= 7-id%8;

ASSERT(0<= whichByte && whichByte < (int)_buffer.size());

char& output= _buffer[whichByte];

output |= 1<<whichBit;

}

bool getBit(int id) const

{

ASSERT(0<=id && id< _bitCount);

ASSERT(0<_buffer.size());

int whichByte= id/ 8;

int whichBit= 7- id%8;

ASSERT(0<= whichByte && whichByte < (int)_buffer.size());

const char& input= _buffer[whichByte];

return input  & 1<<whichBit ? true: false;

}

int getBitCount()

{

return _bitCount;

}

string makeBinaryString()

{

int i;

string ret;

for (i=0;i<_bitCount;i++)

{

char b=getBit(i) ? '1':'0';

ret= ret+b;

}

return ret;

}

};

int main()

{

BitSet set;

set.resize(5);

int i;

for (i=0;i<set.getBitCount();i++)

{

set.setBit(i,true);

cout<<set.makeBinaryString()<<endl;

}

return 0;

}