





from __future__ import annotations

from collections.abc import Iterator
from typing import Any

class        snake_case__    :







						"""simple docstring"""




						def __init__(       self ,       __lowercase  ) ->				Tuple:
									"""simple docstring"""




									a__       :						Any							=  data
									a__       :						Node | None							=  None




class        snake_case__    :







						"""simple docstring"""




						def __init__(       self  ) ->				Optional[int]:
									"""simple docstring"""




									a__       :						Any							=  None
									a__       :						str							=  None

						def __iter__(       self  ) ->				Iterator[Any]:
									"""simple docstring"""




									a__       :						List[str]							=  self.head
									while self.head:
												yield node.data
												a__       :						List[str]							=  node.next
												if node == self.head:
															break

						def __len__(       self  ) ->				int:
									"""simple docstring"""




									return sum(1 for _ in self  )

						def __repr__(       self  ) ->				List[Any]:
									"""simple docstring"""




									return "->".join(str(__lowercase  ) for item in iter(self  )  )

						def 							SCREAMING_SNAKE_CASE__(       self ,       __lowercase  ) ->				None:
									"""simple docstring"""




									self.insert_nth(len(self  ) ,       __lowercase  )

						def 							SCREAMING_SNAKE_CASE__(       self ,       __lowercase  ) ->				None:
									"""simple docstring"""




									self.insert_nth(0 ,       __lowercase  )

						def 							SCREAMING_SNAKE_CASE__(       self ,       __lowercase ,       __lowercase  ) ->				None:
									"""simple docstring"""




									if index < 0 or index > len(self  ):
												raise IndexError("""list index out of range."""  )
									a__       :						str							=  Node(__lowercase  )
									if self.head is None:
												a__       :						Optional[int]							=  new_node  # first node points itself
												a__       :						Tuple							=  new_node
									elif index == 0:  # insert at head
												a__       :						List[str]							=  self.head
												a__       :						Union[str, Any]							=  new_node
									else:
												a__       :						int							=  self.head
												for _ in range(index - 1  ):
															a__       :						List[Any]							=  temp.next
												a__       :						int							=  temp.next
												a__       :						Dict							=  new_node
												if index == len(self  ) - 1:  # insert at tail
															a__       :						str							=  new_node

						def 							SCREAMING_SNAKE_CASE__(       self  ) ->				Optional[Any]:
									"""simple docstring"""




									return self.delete_nth(0  )

						def 							SCREAMING_SNAKE_CASE__(       self  ) ->				Any:
									"""simple docstring"""




									return self.delete_nth(len(self  ) - 1  )

						def 							SCREAMING_SNAKE_CASE__(       self ,       __lowercase = 0  ) ->				Any:
									"""simple docstring"""




									if not 0 <= index < len(self  ):
												raise IndexError("""list index out of range."""  )
									a__       :						Optional[int]							=  self.head
									if self.head == self.tail:  # just one node
												a__       :						Optional[Any]							=  None
									elif index == 0:  # delete head node
												a__       :						List[str]							=  self.tail.next.next
												a__       :						Union[str, Any]							=  self.head.next
									else:
												a__       :						str							=  self.head
												for _ in range(index - 1  ):
															a__       :						Dict							=  temp.next
												a__       :						int							=  temp.next
												a__       :						List[str]							=  temp.next.next
												if index == len(self  ) - 1:  # delete at tail
															a__       :						Optional[Any]							=  temp
									return delete_node.data

						def 							SCREAMING_SNAKE_CASE__(       self  ) ->				bool:
									"""simple docstring"""




									return len(self  ) == 0




def      lowerCAmelCase_					(  )							->	None:







			"""simple docstring"""
			a__       :						List[str]							=  CircularLinkedList()
			assert len(_lowercase) == 0
			assert circular_linked_list.is_empty() is True
			assert str(_lowercase) == ""

			try:
						circular_linked_list.delete_front()
						raise AssertionError  # This should not happen
			except IndexError:
						assert True  # This should happen

			try:
						circular_linked_list.delete_tail()
						raise AssertionError  # This should not happen
			except IndexError:
						assert True  # This should happen

			try:
						circular_linked_list.delete_nth(-1)
						raise AssertionError
			except IndexError:
						assert True

			try:
						circular_linked_list.delete_nth(0)
						raise AssertionError
			except IndexError:
						assert True

			assert circular_linked_list.is_empty() is True
			for i in range(5):
						assert len(_lowercase) == i
						circular_linked_list.insert_nth(_lowercase						,       i + 1)
			assert str(_lowercase) == "->".join(str(_lowercase) for i in range(1						,       6))

			circular_linked_list.insert_tail(6)
			assert str(_lowercase) == "->".join(str(_lowercase) for i in range(1						,       7))
			circular_linked_list.insert_head(0)
			assert str(_lowercase) == "->".join(str(_lowercase) for i in range(0						,       7))

			assert circular_linked_list.delete_front() == 0
			assert circular_linked_list.delete_tail() == 6
			assert str(_lowercase) == "->".join(str(_lowercase) for i in range(1						,       6))
			assert circular_linked_list.delete_nth(2) == 3

			circular_linked_list.insert_nth(2						,       3)
			assert str(_lowercase) == "->".join(str(_lowercase) for i in range(1						,       6))

			assert circular_linked_list.is_empty() is False


if __name__ == "__main__":
		import doctest

		doctest.testmod()









import os
import sys
from contextlib import contextmanager


# Windows only
if os.name == "nt":
		import ctypes
		import msvcrt  # noqa

		class        snake_case__    (ctypes.Structure		):







								"""simple docstring"""




								__lowerCAmelCase					:Dict      =					[("size", ctypes.c_int), ("visible", ctypes.c_byte)]

def      lowerCAmelCase_					(  )							->	List[Any]:







			"""simple docstring"""
			if os.name == "nt":
						a__       :						int							=  CursorInfo()
						a__       :						Union[str, Any]							=  ctypes.windll.kernelaa.GetStdHandle(-11)
						ctypes.windll.kernelaa.GetConsoleCursorInfo(_lowercase						,       ctypes.byref(_lowercase))
						a__       :						List[str]							=  False
						ctypes.windll.kernelaa.SetConsoleCursorInfo(_lowercase						,       ctypes.byref(_lowercase))
			elif os.name == "posix":
						sys.stdout.write("""\033[?25l""")
						sys.stdout.flush()

def      lowerCAmelCase_					(  )							->	Optional[Any]:







			"""simple docstring"""
			if os.name == "nt":
						a__       :						List[Any]							=  CursorInfo()
						a__       :						Optional[int]							=  ctypes.windll.kernelaa.GetStdHandle(-11)
						ctypes.windll.kernelaa.GetConsoleCursorInfo(_lowercase						,       ctypes.byref(_lowercase))
						a__       :						Dict							=  True
						ctypes.windll.kernelaa.SetConsoleCursorInfo(_lowercase						,       ctypes.byref(_lowercase))
			elif os.name == "posix":
						sys.stdout.write("""\033[?25h""")
						sys.stdout.flush()





@contextmanager
def      lowerCAmelCase_					(  )							->	Any:







			"""simple docstring"""
			try:
						hide_cursor()
						yield
			finally:
						show_cursor()




