public static Suit valueOf(char c) {
        switch (c) {
            case 'S':
            case 's':
                return Spades;
            case 'H':
            case 'h':
                return Hearts;
            case 'D':
            case 'd':
                return Diamonds;
            case 'C':
            case 'c':
                return Clubs;
            default:
                return null;
        }
    }