static final long[] maxValueDivs = new long[Character.MAX_RADIX + 1];
    static final int[] maxValueMods = new int[Character.MAX_RADIX + 1];
    static final int[] maxSafeDigits = new int[Character.MAX_RADIX + 1];

    static {
      BigInteger overflow = BigInteger.ONE.shiftLeft(64);
      for (int i = Character.MIN_RADIX; i <= Character.MAX_RADIX; i++) {
        maxValueDivs[i] = divide(MAX_VALUE, i);

   *     and {@link Character#MAX_RADIX}.
   * @since 13.0
   */
  public static String toString(byte x, int radix) {
    checkArgument(
        radix >= Character.MIN_RADIX && radix <= Character.MAX_RADIX,
        "radix (%s) must be between Character.MIN_RADIX and Character.MAX_RADIX",
        radix);
    // Benchmarks indicate this is probably not worth optimizing.

   *
   * @throws NumberFormatException if the string does not contain a parsable unsigned {@code long}
   *     value, or {@code radix} is not between {@link Character#MIN_RADIX} and {@link
   *     Character#MAX_RADIX}
   */
  @CanIgnoreReturnValue
  public static UnsignedLong valueOf(String string, int radix) {
    return fromLongBits(UnsignedLongs.parseUnsignedLong(string, radix));
  }

  /**

   *
   * @param string the string containing the unsigned integer representation to be parsed.
   * @param radix the radix to use while parsing {@code s}; must be between {@link
   *     Character#MIN_RADIX} and {@link Character#MAX_RADIX}.
   * @throws NumberFormatException if the string does not contain a valid unsigned {@code int}, or
   *     if supplied radix is invalid.
   * @throws NullPointerException if {@code s} is null (in contrast to {@link

   *     Character.MAX_RADIX}
   * @throws NullPointerException if {@code string} is {@code null}
   * @since 19.0
   */
  public static @Nullable Long tryParse(String string, int radix) {
    if (checkNotNull(string).isEmpty()) {
      return null;
    }
    if (radix < Character.MIN_RADIX || radix > Character.MAX_RADIX) {
      throw new IllegalArgumentException(

    // Valid radix values are Character.MIN_RADIX to Character.MAX_RADIX,
    // inclusive.
    assertThrows(
        NumberFormatException.class,
        () -> UnsignedBytes.parseUnsignedByte("0", Character.MIN_RADIX - 1));

    assertThrows(
        NumberFormatException.class,
        () -> UnsignedBytes.parseUnsignedByte("0", Character.MAX_RADIX + 1));

      for (int radix = Character.MIN_RADIX; radix <= Character.MAX_RADIX; radix++) {
        assertThat(UnsignedInts.parseUnsignedInt(Long.toString(a, radix), radix))
            .isEqualTo((int) a);
      }
    }
  }

  public void testParseIntWithRadixLimits() {
    // loops through all legal radix values.
    for (int r = Character.MIN_RADIX; r <= Character.MAX_RADIX; r++) {
      int radix = r;

    // Valid radix values are Character.MIN_RADIX to Character.MAX_RADIX,
    // inclusive.
    assertThrows(
        NumberFormatException.class,
        () -> UnsignedBytes.parseUnsignedByte("0", Character.MIN_RADIX - 1));

    assertThrows(
        NumberFormatException.class,
        () -> UnsignedBytes.parseUnsignedByte("0", Character.MAX_RADIX + 1));

    // Valid radix values are Character.MIN_RADIX to Character.MAX_RADIX, inclusive.
    assertThrows(
        NumberFormatException.class,
        () -> UnsignedLongs.parseUnsignedLong("0", Character.MIN_RADIX - 1));

    assertThrows(
        NumberFormatException.class,
        () -> UnsignedLongs.parseUnsignedLong("0", Character.MAX_RADIX + 1));

    // The radix is used as an array index, so try a negative value.

    // Valid radix values are Character.MIN_RADIX to Character.MAX_RADIX, inclusive.
    assertThrows(
        NumberFormatException.class,
        () -> UnsignedLongs.parseUnsignedLong("0", Character.MIN_RADIX - 1));

    assertThrows(
        NumberFormatException.class,
        () -> UnsignedLongs.parseUnsignedLong("0", Character.MAX_RADIX + 1));

    // The radix is used as an array index, so try a negative value.