'''simple docstring'''
def 				__UpperCamelCase (					__UpperCAmelCase  :					Tuple ,   __UpperCAmelCase  :					List[Any]			)							->	int:
  sequence.append(lowerCAmelCase_			)

  lowercase				:							Union[str, Any]									=   0
  while sequence[index] != target:
    index += 1

  sequence.pop()

  if index == len(lowerCAmelCase_			):
    return None

  return index


if __name__ == "__main__":
 _A		:      Dict						   =input('''Enter numbers separated by comma:\n''').strip()
 _A		:      str						   =[int(item) for item in user_input.split(''',''')]

 _A		:      int						   =input('''Enter a single number to be found in the list:\n''')
 _A		:      Tuple						   =int(target_input)
 _A		:      Optional[int]						   =sentinel_linear_search(sequence, target)
 if result is not None:
  print(f"""{target} found at positions: {result}""")
 else:
  print('''Not found''')



def       lowerCAmelCase			(		lowerCAmelCase_			)->			int:
				lowerCAmelCase_			:   Optional[int]     					=					len(lowerCAmelCase_			)
				if n in (0, 1):
								return 0
				return sum(query * (n - i - 1) for i, query in enumerate(sorted(lowerCAmelCase_			)			)			)


if __name__ == "__main__":
						import doctest

						doctest.testmod()