

"""simple docstring"""


from __future__ import annotations






def        a__       (       __SCREAMING_SNAKE_CASE					)      ->      float:
		__lowerCAmelCase:			Any        =     0.00
		__lowerCAmelCase:			Tuple        =     0
		for resistor in resistors:
				if resistor <= 0:
						__lowerCAmelCase:			Dict        =     F"Resistor at index {index} has a negative or zero value!"
						raise ValueError(__SCREAMING_SNAKE_CASE					)
				first_sum += 1 / float(__SCREAMING_SNAKE_CASE					)
				index += 1
		return 1 / first_sum






def        a__       (       __SCREAMING_SNAKE_CASE					)      ->      float:
		__lowerCAmelCase:			Optional[Any]        =     0.00
		__lowerCAmelCase:			int        =     0
		for resistor in resistors:
				sum_r += resistor
				if resistor < 0:
						__lowerCAmelCase:			Tuple        =     F"Resistor at index {index} has a negative value!"
						raise ValueError(__SCREAMING_SNAKE_CASE					)
				index += 1
		return sum_r


if __name__ == "__main__":
			import doctest

			doctest.testmod()





'''simple docstring'''





from collections import defaultdict






def 				_lowerCAmelCase			(   __magic_name__						:     int						)				->  int:
						lowercase :							Optional[Any]    		=1
						lowercase :							Union[str, Any]    		=True
						for v in tree[start]:
												if v not in visited:
																		ret += dfs(__magic_name__						)
						if ret % 2 == 0:
												cuts.append(__magic_name__						)
						return ret






def 				_lowerCAmelCase			(   )				->  int:
						dfs(1						)


if __name__ == "__main__":
							UpperCamelCase_						,   UpperCamelCase_    						=       10, 9
							UpperCamelCase_    						=       defaultdict(list)
							UpperCamelCase_    						=       {}
							UpperCamelCase_    						=       []
							UpperCamelCase_    						=       0
							UpperCamelCase_    						=       [(2, 1), (3, 1), (4, 3), (5, 2), (6, 1), (7, 2), (8, 6), (9, 8), (10, 8)]
							for u, v in edges:
														tree[u].append(v)
														tree[v].append(u)
							even_tree()
							print(len(cuts) - 1)





