private static boolean containsLettersOrDigits(CharSequence seq, int start, int end) {
    for (int i = start; i < end; i++) {
      if (Character.isLetterOrDigit(seq.charAt(i))) {
        return true;
      }
    }
    return false;
  }
private static boolean containsLettersOrDigits(CharSequence seq, int start, int end)