#ifndef FIB_COLLJGBP
#define FIB_COLLJGBP

// fibonacci sequence.
// 0,1,1,2,3,5,8,13,21,34,...
class FibSeq
{
public:
	typedef uint64_t int_type;
	FibSeq(int_type limit) :
	    m_limit(limit), m_cur(0), m_next(1) {}

	void Reset()
	{
		m_cur = 0;
		m_next = 1;
	}
	void ResetLimit(const int_type v)
	{
		m_limit = v;
		Reset();
	}

	int_type Limit() const { return m_limit; }
	int_type Cur() const { return m_cur; }
	int_type Inc()
	{
		if (m_next < m_limit) {
			m_next = m_next + m_cur;
			m_cur = m_next - m_cur;
		} else {
			m_cur = m_limit;
		}
		return Cur();
	}

private:
	int_type m_limit;
	int_type m_cur;
	int_type m_next;
};

#endif // end of include guard: FIB_COLLJGBP