





def  A					(				UpperCAmelCase					):


					if not isinstance(snake_case_	,	snake_case_					):
										raise ValueError("Input series is not valid, valid series - [1, 2/3, 2]"					)
					if len(snake_case_					) == 0:
										raise ValueError("Input list must be a non empty list"					)
					if len(snake_case_					) == 1 and series[0] != 0:
										return True
					_snake_case							:       Optional[int]												= []
					_snake_case							:       List[str]												= len(snake_case_					)
					for i in range(0	,	snake_case_					):
										if series[i] == 0:
															raise ValueError("Input series cannot have 0 as an element"					)
										rec_series.append(1 / series[i]					)
					_snake_case							:       Optional[int]												= rec_series[1] - rec_series[0]
					for index in range(2	,	snake_case_					):
										if rec_series[index] - rec_series[index - 1] != common_diff:
															return False
					return True







def  A					(				UpperCAmelCase					):


					if not isinstance(snake_case_	,	snake_case_					):
										raise ValueError("Input series is not valid, valid series - [2, 4, 6]"					)
					if len(snake_case_					) == 0:
										raise ValueError("Input list must be a non empty list"					)
					_snake_case							:       str												= 0
					for val in series:
										answer += 1 / val
					return len(snake_case_					) / answer


if __name__ == "__main__":
							import doctest

							doctest.testmod()





def 				__SCREAMING_SNAKE_CASE    (     snake_case_		):

						'''simple docstring'''


						return int(snake_case_		) if x - int(snake_case_		) >= 0 else int(snake_case_		) - 1


if __name__ == "__main__":
				import doctest

				doctest.testmod()




