bitset C++

bitset.h

class dyn_bitset
{
	using byte_t = uint_fast8_t;

private:
	int _size, _bits;
	byte_t* _buf;

public:
	dyn_bitset(int n)
			: _size((n + 7) >> 3), _bits(n), _buf(new byte_t[_size] { })
	{
	}

	dyn_bitset(const dyn_bitset& b)
			: _size(b._size), _bits(b._bits), _buf(new byte_t[_size])
	{
		copy(b._buf, b._buf + _size, _buf);
	}

	dyn_bitset(dyn_bitset&& b)
			: _size(b._size), _bits(b._bits), _buf(new byte_t[_size])
	{
		copy(b._buf, b._buf + _size, _buf);
		delete[] b._buf;
		b._buf = nullptr;
		b._size = 0;
		b._bits = 0;
	}

	~dyn_bitset()
	{
		delete[] _buf;
	}

	dyn_bitset& operator=(const dyn_bitset& b)
	{
		delete[] _buf;
		_size = b._size;
		_buf = new byte_t[_size];
		_bits = b._bits;
		copy(b._buf, b._buf + _size, _buf);
		return *this;
	}

	dyn_bitset& operator=(dyn_bitset&& b)
	{
		_size = b._size;
		_buf = b._buf;
		_bits = b._bits;
		b._buf = nullptr;
		b._size = 0;
		b._bits = 0;
		return *this;
	}

	int size() const
	{
		return _size;
	}

	int bits() const
	{
		return _bits;
	}

	const bool operator[](int n) const
	{
		return (_buf[n >> 3] >> (n & 7)) & 1;
	}

	void set(int n)
	{
		_buf[n >> 3] |= 1 << (n & 7);
	}

	void clear(int n)
	{
		_buf[n >> 3] &= ~(1 << (n & 7));
	}

	bool operator==(const dyn_bitset& b1) const
	{
		if (_size != b1._size)
			return false;
		byte_t *p1 = _buf, *p2 = b1._buf;
		for (int i = 0; i < _size; i++, ++p1, ++p2)
			if (*p1 != *p2)
				return false;
		return true;
	}

	bool operator!=(const dyn_bitset& b1) const
	{
		return !(*this == b1);
	}

	string to_string() const
	{
		ostringstream oss;
		int bi = bits();
		for (int i = 0; i < bi; i++)
			oss << ((*this)[i] ? '1' : '0');
		return oss.str();
	}

	dyn_bitset& operator&=(const dyn_bitset& b)
	{
		byte_t *p1 = _buf, *p2 = b._buf;
		for (int i = 0; i < _size; i++, ++p1, ++p2)
			*p1 &= *p2;
		return *this;
	}

	dyn_bitset& operator|=(const dyn_bitset& b)
	{
		byte_t *p1 = _buf, *p2 = b._buf;
		for (int i = 0; i < _size; i++, ++p1, ++p2)
			*p1 |= *p2;
		return *this;
	}

	dyn_bitset& operator^=(const dyn_bitset& b)
	{
		byte_t *p1 = _buf, *p2 = b._buf;
		for (int i = 0; i < _size; i++, ++p1, ++p2)
			*p1 ^= *p2;
		return *this;
	}
};

dyn_bitset operator&(dyn_bitset b, const dyn_bitset& b1)
{
	return (b &= b1);
}

dyn_bitset operator|(dyn_bitset b, const dyn_bitset& b1)
{
	return (b |= b1);
}

dyn_bitset operator^(dyn_bitset b, const dyn_bitset& b1)
{
	return (b ^= b1);
}