




"""simple docstring"""

def 				a (						__snake_case     :				list  ):



				'''simple docstring'''





				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
				UpperCAmelCase_					:List[str]      			=      []
				UpperCAmelCase_					:List[Any]      			=      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]  )
				UpperCAmelCase_					: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 (						__snake_case     :				list  ):



				'''simple docstring'''





				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'''  )
				UpperCAmelCase_					:Optional[int]      			=      0
				for val in series:
								answer += 1 / val
				return len(__snake_case  ) / answer


if __name__ == "__main__":
						import doctest

						doctest.testmod()











"""simple docstring"""

def 				a (						__snake_case     :				int  ):



				'''simple docstring'''





				if not isinstance(__snake_case,    __snake_case  ) or number < 0:
								raise ValueError('''Input must be a non-negative integer'''  )

				UpperCAmelCase_					:Optional[Any]      			=      number & ~(number - 1)
				UpperCAmelCase_					:List[str]      			=      0
				while intermediate:
								intermediate >>= 1
								index += 1
				return index - 1


if __name__ == "__main__":
						import doctest

						doctest.testmod(verbose=True)


