




def 		SCREAMING_SNAKE_CASE__   (       lowercase	)    ->  Union[str, Any]:







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




def 		SCREAMING_SNAKE_CASE__   (       lowercase	)    ->  List[Any]:







   if not head or not head.next:
      return True

   # 1. Get the midpoint (slow)
   snake_case :							Any           =			head
   while fast and fast.next:
      snake_case :							Union[str, Any]           =			fast.next.next, slow.next

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

   # 3. Comparison
   while stack:
      if stack.pop() != cur.val:
         return False
      snake_case :							List[Any]           =			cur.next

   return True




def 		SCREAMING_SNAKE_CASE__   (       lowercase	)    ->  Tuple:







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












"""simple docstring"""



def 						__lowercase	(  snake_case_    :    list		)  ->float:



    '''simple docstring'''







    __A       :		Tuple							=	0
    while len(snake_case_		) > 1:
        __A       :		List[Any]							=	0
        # Consider two files with minimum cost to be merged
        for _ in range(2		):
            __A       :		Dict							=	files.index(min(snake_case_		)		)
            temp += files[min_index]
            files.pop(snake_case_		)
        files.append(snake_case_		)
        optimal_merge_cost += temp
    return optimal_merge_cost


if __name__ == "__main__":
       import doctest

       doctest.testmod()




