public void doGeneralCheck(String romanNr) {
        if (!checkValidLetters(romanNr)) {
            System.out.println("invalid");
            System.exit(0);
        }
        if (!checkThreeConsecLetters(romanNr) || !checkRomanNr(romanNr)) {
            System.out.println("invalid");
            System.exit(0);
        }
        System.out.println("valid");
        System.exit(0);
    }