


'''simple docstring'''







def        __lowercase						(      __SCREAMING_SNAKE_CASE		)				->					bool:
     """simple docstring"""




     __a       =   [int(__SCREAMING_SNAKE_CASE		) for i in ip_va_address.split("""."""		) if i.isdigit()]
     return len(__SCREAMING_SNAKE_CASE		) == 4 and all(0 <= int(__SCREAMING_SNAKE_CASE		) <= 254 for octet in octets		)


if __name__ == "__main__":
 SCREAMING_SNAKE_CASE_      =			input().strip()
 SCREAMING_SNAKE_CASE_      =			'valid' if is_ip_va_address_valid(ip) else 'invalid'
 print(f"""{ip} is a {valid_or_invalid} IP v4 address.""")










'''simple docstring'''







def        __lowercase						(      __SCREAMING_SNAKE_CASE = 100_0000		)				->					int:
     """simple docstring"""




     __a       =   1
     __a       =   1
     __a       =   {1: 1}

     for inputa in range(2				,  __SCREAMING_SNAKE_CASE		):
          __a       =   0
          __a       =   inputa

          while True:
               if number in counters:
                    counter += counters[number]
                    break
               if number % 2 == 0:
                    number //= 2
                    counter += 1
               else:
                    __a       =   (3 * number) + 1
                    counter += 1

          if inputa not in counters:
               __a       =   counter

          if counter > pre_counter:
               __a       =   inputa
               __a       =   counter
     return largest_number


if __name__ == "__main__":
 print(solution(int(input().strip())))






