




import math




def 							_UpperCAmelCase  (UpperCamelCase_ : float      ,    UpperCamelCase_ : float       ):
				return math.pow(UpperCamelCase_      ,    2       ) - a




def 							_UpperCAmelCase  (UpperCamelCase_ : float       ):
				return 2 * x




def 							_UpperCAmelCase  (UpperCamelCase_ : float       ):
				_lowerCAmelCase    :    Union[str, Any]										=      2.0

				while start <= a:
								_lowerCAmelCase    :    Dict										=      math.pow(UpperCamelCase_      ,    2       )

				return start




def 							_UpperCAmelCase  (UpperCamelCase_ : float      ,    UpperCamelCase_ : int = 9999      ,    UpperCamelCase_ : float = 0.00_000_000_000_001       ):

				if a < 0:
								raise ValueError("""math domain error"""       )

				_lowerCAmelCase    :    Optional[Any]										=      get_initial_point(UpperCamelCase_       )

				for _ in range(UpperCamelCase_       ):
								_lowerCAmelCase    :    List[str]										=      value
								_lowerCAmelCase    :    str										=      value - fx(UpperCamelCase_      ,    UpperCamelCase_       ) / fx_derivative(UpperCamelCase_       )
								if abs(prev_value - value       ) < tolerance:
												return value

				return value


if __name__ == "__main__":
	from doctest import testmod

	testmod()







def 							_UpperCAmelCase  (UpperCamelCase_ : str       ):
				'''simple docstring'''
				_lowerCAmelCase    :    List[str]										=      [int(UpperCamelCase_       ) for i in ip_va_address.split("""."""       ) if i.isdigit()]
				return len(UpperCamelCase_       ) == 4 and all(0 <= int(UpperCamelCase_       ) <= 254 for octet in octets       )


if __name__ == "__main__":
	_lowerCamelCase      :  List[str]      						=						input().strip()
	_lowerCamelCase      :  int      						=						"valid" if is_ip_va_address_valid(ip) else "invalid"
	print(F'''{ip} is a {valid_or_invalid} IP v4 address.''')

