'''simple docstring'''




def _lowercase	(      lowerCamelCase__							,    lowerCamelCase__						)					->       float:





       """simple docstring"""


       if discount_rate < 0:
              raise ValueError("Discount rate cannot be negative"						)
       if not cash_flows:
              raise ValueError("Cash flows list cannot be empty"						)
       __UpperCAmelCase  :				Tuple       				=		sum(
           cash_flow / ((1 + discount_rate) ** i) for i, cash_flow in enumerate(lowerCamelCase__						)						)
       return round(lowerCamelCase__							,    ndigits=2						)


if __name__ == "__main__":
   import doctest

   doctest.testmod()







'''simple docstring'''




def _lowercase	(      lowerCamelCase__ = 100						)					->       int:





       """simple docstring"""


       __UpperCAmelCase  :				Optional[Any]       				=		(n * (n + 1) // 2) ** 2
       __UpperCAmelCase  :				Any       				=		n * (n + 1) * (2 * n + 1) // 6
       return sum_cubes - sum_squares


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






