






def __A    (      __lowerCAmelCase	)->  List[str]:





						"""simple docstring"""



						if not head:
												return True
						# split the list to two parts
						_UpperCAmelCase					, _UpperCAmelCase									=			head.next, head
						while fast and fast.next:
												_UpperCAmelCase									=			fast.next.next
												_UpperCAmelCase									=			slow.next
						_UpperCAmelCase									=			slow.next
						_UpperCAmelCase									=			None  # Don't forget here! But forget still works!
						# reverse the second part
						_UpperCAmelCase									=			None
						while second:
												_UpperCAmelCase									=			second.next
												_UpperCAmelCase									=			node
												_UpperCAmelCase									=			second
												_UpperCAmelCase									=			nxt
						# compare two parts
						# second part has the same or one less node
						while node:
												if node.val != head.val:
																		return False
												_UpperCAmelCase									=			node.next
												_UpperCAmelCase									=			head.next
						return True


def __A    (      __lowerCAmelCase	)->  List[Any]:





						"""simple docstring"""



						if not head or not head.next:
												return True

						# 1. Get the midpoint (slow)
						_UpperCAmelCase									=			_UpperCAmelCase									=			_UpperCAmelCase									=			head
						while fast and fast.next:
												_UpperCAmelCase					, _UpperCAmelCase									=			fast.next.next, slow.next

						# 2. Push the second half into the stack
						_UpperCAmelCase									=			[slow.val]
						while slow.next:
												_UpperCAmelCase									=			slow.next
												stack.append(slow.val	)

						# 3. Comparison
						while stack:
												if stack.pop() != cur.val:
																		return False
												_UpperCAmelCase									=			cur.next

						return True


def __A    (      __lowerCAmelCase	)->  int:





						"""simple docstring"""



						if not head or not head.next:
												return True
						_UpperCAmelCase									=			{}
						_UpperCAmelCase									=			0
						while head:
												if head.val in d:
																		d[head.val].append(__lowerCAmelCase	)
												else:
																		_UpperCAmelCase									=			[pos]
												_UpperCAmelCase									=			head.next
												pos += 1
						_UpperCAmelCase									=			pos - 1
						_UpperCAmelCase									=			0
						for v in d.values():
												if len(__lowerCAmelCase	) % 2 != 0:
																		middle += 1
												else:
																		_UpperCAmelCase									=			0
																		for i in range(0 ,		len(__lowerCAmelCase	)	):
																								if v[i] + v[len(__lowerCAmelCase	) - 1 - step] != checksum:
																														return False
																								step += 1
												if middle > 1:
																		return False
						return True






"""simple docstring"""


from __future__ import annotations


def 					UpperCAmelCase__       (snake_case__							:					list[int]		,   snake_case__							:					int    ):
  """simple docstring"""

  if len(snake_case__    ) < k or k < 0:
    raise ValueError("""Invalid Input"""    )
  _snake_case							:		Optional[int]								=  sum(array[:k]    )
  for i in range(len(snake_case__    ) - k    ):
    _snake_case							:		Optional[Any]								=  current_sum - array[i] + array[i + k]
    _snake_case							:		List[str]								=  max(snake_case__		,   snake_case__    )
  return max_sum


if __name__ == "__main__":
     from doctest import testmod
     from random import randint

     testmod()
     A_						=				[randint(-10_00, 10_00) for i in range(1_00)]
     A_						=				randint(0, 1_10)
     print(F'''The maximum sum of {k} consecutive elements is {max_sum_in_array(array,k)}''')


