public static String lettertonumber(String code, int start) {
        char[] codeline = code.toCharArray();
        String result = "";
        for(char element : codeline) {
            if(Character.toLowerCase(element) >= 'a' && Character.toLowerCase(element) <= 'z')
                result += (Character.toLowerCase(element) - 'a') + start;
            else result += element;
        }
        return result;
    }