

'''simple docstring'''

def 				lowercase (					__magic_name__							):



					'''simple docstring'''







					if not isinstance(__magic_name__			,   __magic_name__							):
										UpperCAmelCase		:							Any        =       F"Input value of [number={number}] must be an integer"
										raise TypeError(__magic_name__							)
					if number < 1:
										raise ValueError("Input must be a positive integer"							)
					return number * (2 * number - 1)


if __name__ == "__main__":
				import doctest

				doctest.testmod()



'''simple docstring'''

from __future__ import annotations







class   UpperCamelCase__   :


		"""simple docstring"""

		def __init__(			self   ,      snake_case      ):


							'''simple docstring'''

							UpperCAmelCase		:							str        =       data
							UpperCAmelCase		:							Dict        =       None







class   UpperCamelCase__   :


		"""simple docstring"""

		def __init__(			self      ):


							'''simple docstring'''

							UpperCAmelCase		:							str        =       None







		def 				A_	(			self   ,      snake_case      ):


							'''simple docstring'''

							UpperCAmelCase		:							int        =       Node(snake_case      )
							UpperCAmelCase		:							Optional[int]        =       self.head
							UpperCAmelCase		:							Union[str, Any]        =       new_node
							return self.head.data







		def 				A_	(			self      ):


							'''simple docstring'''

							UpperCAmelCase		:							Dict        =       self.head
							UpperCAmelCase		:							str        =       self.head
							if self.head:
												while fast_pointer and fast_pointer.next:
																	UpperCAmelCase		:							List[str]        =       fast_pointer.next.next
																	UpperCAmelCase		:							Any        =       slow_pointer.next
												return slow_pointer.data
							else:
												print("No element found."      )
												return None


if __name__ == "__main__":
				a       :      List[str]  	=			LinkedList()
				for _ in range(int(input().strip())):
								a       :      str  	=			int(input().strip())
								link.push(data)
				print(link.middle_element())
