
"""simple docstring"""



def 	__snake_case  (    SCREAMING_SNAKE_CASE:					int						):






							"""simple docstring"""



							_lowerCAmelCase  	=			(1 + 24 * n) ** 0.5
							return ((1 + root) / 6) % 1 == 0






def 	__snake_case  (    SCREAMING_SNAKE_CASE:					int = 5000						):






							"""simple docstring"""



							_lowerCAmelCase  	=			[(i * (3 * i - 1)) // 2 for i in range(1     ,  SCREAMING_SNAKE_CASE						)]
							for i, pentagonal_i in enumerate(SCREAMING_SNAKE_CASE						):
														for j in range(SCREAMING_SNAKE_CASE     ,  len(SCREAMING_SNAKE_CASE						)						):
																					_lowerCAmelCase  	=			pentagonal_nums[j]
																					_lowerCAmelCase  	=			pentagonal_i + pentagonal_j
																					_lowerCAmelCase  	=			pentagonal_j - pentagonal_i
																					if is_pentagonal(SCREAMING_SNAKE_CASE						) and is_pentagonal(SCREAMING_SNAKE_CASE						):
																												return b

							return -1


if __name__ == "__main__":
	print(f'{solution() = }')








"""simple docstring"""



def 	__snake_case  (    SCREAMING_SNAKE_CASE:					str						):






							"""simple docstring"""



							_lowerCAmelCase  	=			[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__":
	_snake_case          =						input().strip()
	_snake_case          =						'''valid''' if is_ip_va_address_valid(ip) else '''invalid'''
	print(f'{ip} is a {valid_or_invalid} IP v4 address.')






