docs: private static void determineFirstDigit(StringBuilder resultString, int lgPatternFound)
        throws NotFoundException {
      for (int d = 0; d < 10; d++) {
        if (lgPatternFound == FIRST_DIGIT_ENCODINGS[d]) {
          resultString.insert(0, (char) ('0' + d));
          return;
        }
      }
      throw NotFoundException.getNotFoundInstance();
    }