@Contract("null -> false")
  public static boolean isNotNegativeNumber(@Nullable CharSequence s) {
    if (s == null) {
      return false;
    }
    for (int i = 0; i < s.length(); i++) {
      if (!isDecimalDigit(s.charAt(i))) {
        return false;
      }
    }
    return true;
  }
@Contract("null -> false")
  public static boolean isNotNegativeNumber(@Nullable CharSequence s)