#include <iostream>
#include <string>

using namespace std;

enum class ColorT: char {RED, GREEN, BLUE, UNKNOWN};
const ColorT FIRST_COLOR = static_cast<ColorT>(0);

ColorT NextColorT(ColorT c);
string ColorTToString(ColorT c);
ColorT StringToColorT(string s);


// need a dummy int param to show it is i++ and not ++i
ColorT operator ++(ColorT & c, int ) {
   return c = NextColorT(c);
}


ostream & operator << (ostream & s ,  const ColorT &  c) {
    s << ColorTToString(c);
    return s;
}

enum struct MoodsT { HAPPY, SAD, BLUE, UNKNOWN};

int main() {
    MoodsT myMood{MoodsT::BLUE};
   

    if (myMood == MoodsT::BLUE) {
       cout << "I'm sorry you are unhappy" << endl;
    }

    for(ColorT i = FIRST_COLOR; i != ColorT::UNKNOWN; i = NextColorT(i)) {
        cout << ColorTToString(i) << endl;
    }

    for (auto i = FIRST_COLOR; i != ColorT::UNKNOWN; i++) {
        cout << i << endl;
    }

    return 0;


}

string ColorTToString(ColorT c){
    switch(c) {
        case ColorT:: RED:
           return "Red";
        case ColorT:: GREEN:
           return "Green";
        case ColorT:: BLUE:
           return "Blue";
        case ColorT:: UNKNOWN:
        default:
           return "Unknown";
    }
    return "Unknown";
}


ColorT NextColorT(ColorT c){
    if (c != ColorT::UNKNOWN) {
        return static_cast<ColorT>(static_cast<int>(c) +1);
    }
    return ColorT::UNKNOWN;
}