return Objects.equals(stringPart, that.stringPart) && Objects.equals(digitPart, that.digitPart);
        }

        @Override
        public int hashCode() {
            return Objects.hash(stringPart, digitPart);
        }

        @Override
        public String toString() {
            return stringPart.toString() + digitPart.toString();
        }
    }

    /**