class Lights
{
public:
    enum Elo
    {
        c1 = 1,
        c2 = 2,
        c3 = 3,
        c4 = 4
    };
    bool red() const
    {
        return redLight;
    }
    bool yellow() const
    {
        return yellowLight;
    }
    bool green() const
    {
        return greenLight;
    }
    void flip()
    {
        switch (lightSwitch)
        {
        case c1:
            redLight = true; yellowLight = true; greenLight = false;
            lightSwitch = c2;
            break;
        case c2:
            redLight = false; yellowLight = false; greenLight = true;
            lightSwitch = c3;
            break;
        case c3:
            redLight = false; yellowLight = true; greenLight = false;
            lightSwitch = c4;
            break;
        case c4:
            redLight = true; yellowLight = false; greenLight = false;
            lightSwitch = c1;
            break;
        default:
            break;
        }
    }
private:
    bool yellowLight = false;
    bool greenLight = false;
    bool redLight = true;
    int lightSwitch = 1;
};