

'''simple docstring'''



from math import factorial
def 						__lowerCamelCase       (   __snake_case     :		Union[str, Any] = 20       )       ->							int:






						"""simple docstring"""





						A__     :   List[str]      =2 * n  # middle entry of odd rows starting at row 3 is the solution for n = 1,
						# 2, 3,...
						A__     :   Optional[Any]      =n // 2

						return int(factorial(_SCREAMING_SNAKE_CASE       ) / (factorial(_SCREAMING_SNAKE_CASE       ) * factorial(n - k       ))       )


if __name__ == "__main__":
		import sys

		if len(sys.argv) == 1:
				print(solution(20))
		else:
				try:
						__snake_case :	List[Any]      						=			int(sys.argv[1])
						print(solution(n))
				except ValueError:
						print('Invalid entry - please enter a number.')







def      A      (      _SCREAMING_SNAKE_CASE = 100_0000    )	-> int:
       lowerCamelCase   :      Tuple			 =					1
       lowerCamelCase   :      int			 =					1
       lowerCamelCase   :      Optional[Any]			 =					{1: 1}

       for inputa in range(2 ,_SCREAMING_SNAKE_CASE    ):
              lowerCamelCase   :      Union[str, Any]			 =					0
              lowerCamelCase   :      List[str]			 =					inputa

              while True:
                     if number in counters:
                            counter += counters[number]
                            break
                     if number % 2 == 0:
                            number //= 2
                            counter += 1
                     else:
                            lowerCamelCase   :      str			 =					(3 * number) + 1
                            counter += 1

              if inputa not in counters:
                     lowerCamelCase   :      str			 =					counter

              if counter > pre_counter:
                     lowerCamelCase   :      str			 =					inputa
                     lowerCamelCase   :      Any			 =					counter
       return largest_number


if __name__ == "__main__":
       print(solution(int(input().strip())))






