class foo
{
public:
    foo() noexcept : m_index(0)
    {
    }

    void operator ++ () noexcept
    {
        if (m_index < 8)
            ++m_index;
        else
            m_index = 0;
    }

    char value() const noexcept
    {
        return m_value_jump[m_index];
    }

    private:
    char m_index;
    static constexpr std::array<const char, 8> m_value_jump = { 3,8,4,3,7,0,1,1 }; //random values
};