




'''simple docstring'''


from __future__ import annotations

from collections.abc import Iterator
from typing import Any

class     A					:







							def __init__(						self :						Any							,    lowerCAmelCase_ :						Any      )    ->							Tuple:


														"""simple docstring"""


														_a			  =       data
														_a			  =       None



class     A					:







							def __init__(						self :						List[Any]      )    ->							Union[str, Any]:


														"""simple docstring"""


														_a			  =       None
														_a			  =       None







							def __iter__(						self :						Optional[int]      )    ->							Iterator[Any]:


														"""simple docstring"""


														_a			  =       self.head
														while self.head:
																					yield node.data
																					_a			  =       node.next
																					if node == self.head:
																												break







							def __len__(						self :						Any      )    ->							int:


														"""simple docstring"""


														return sum(1 for _ in self      )







							def __repr__(						self :						Tuple      )    ->							Dict:


														"""simple docstring"""


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







							def      __lowerCAmelCase    (						self :						Tuple							,    lowerCAmelCase_ :						Any      )    ->							None:


														"""simple docstring"""


														self.insert_nth(len(self      )							,    lowerCAmelCase_      )







							def      __lowerCAmelCase    (						self :						Optional[int]							,    lowerCAmelCase_ :						Any      )    ->							None:


														"""simple docstring"""


														self.insert_nth(0							,    lowerCAmelCase_      )







							def      __lowerCAmelCase    (						self :						Dict							,    lowerCAmelCase_ :						int							,    lowerCAmelCase_ :						Any      )    ->							None:


														"""simple docstring"""


														if index < 0 or index > len(self      ):
																					raise IndexError('''list index out of range.'''      )
														_a			  =       Node(lowerCAmelCase_      )
														if self.head is None:
																					_a			  =       new_node  # first node points itself
																					_a			  =       _a			  =       new_node
														elif index == 0:  # insert at head
																					_a			  =       self.head
																					_a			  =       _a			  =       new_node
														else:
																					_a			  =       self.head
																					for _ in range(index - 1      ):
																												_a			  =       temp.next
																					_a			  =       temp.next
																					_a			  =       new_node
																					if index == len(self      ) - 1:  # insert at tail
																												_a			  =       new_node







							def      __lowerCAmelCase    (						self :						Tuple      )    ->							Optional[Any]:


														"""simple docstring"""


														return self.delete_nth(0      )







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


														"""simple docstring"""


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







							def      __lowerCAmelCase    (						self :						List[str]							,    lowerCAmelCase_ :						int = 0      )    ->							Any:


														"""simple docstring"""


														if not 0 <= index < len(self      ):
																					raise IndexError('''list index out of range.'''      )
														_a			  =       self.head
														if self.head == self.tail:  # just one node
																					_a			  =       _a			  =       None
														elif index == 0:  # delete head node
																					_a			  =       self.tail.next.next
																					_a			  =       self.head.next
														else:
																					_a			  =       self.head
																					for _ in range(index - 1      ):
																												_a			  =       temp.next
																					_a			  =       temp.next
																					_a			  =       temp.next.next
																					if index == len(self      ) - 1:  # delete at tail
																												_a			  =       temp
														return delete_node.data







							def      __lowerCAmelCase    (						self :						Union[str, Any]      )    ->							bool:


														"""simple docstring"""


														return len(self      ) == 0



def 	snake_case_					():





							'''simple docstring'''


							_a			  =       CircularLinkedList()
							assert len(UpperCamelCase   ) == 0
							assert circular_linked_list.is_empty() is True
							assert str(UpperCamelCase   ) == ""

							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(UpperCamelCase   ) == i
														circular_linked_list.insert_nth(UpperCamelCase				,		i + 1   )
							assert str(UpperCamelCase   ) == "->".join(str(UpperCamelCase   ) for i in range(1				,		6   )   )

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

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

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

							assert circular_linked_list.is_empty() is False


if __name__ == "__main__":
				import doctest

				doctest.testmod()







'''simple docstring'''


import os
import sys
from contextlib import contextmanager


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

				class     A					(	ctypes.Structure					):
											# _fields is a specific attr expected by ctypes
											lowercase_           =       [('size', ctypes.c_int), ('visible', ctypes.c_byte)]
def 	snake_case_					():





							'''simple docstring'''


							if os.name == "nt":
														_a			  =       CursorInfo()
														_a			  =       ctypes.windll.kernelaa.GetStdHandle(-11   )
														ctypes.windll.kernelaa.GetConsoleCursorInfo(UpperCamelCase				,		ctypes.byref(UpperCamelCase   )   )
														_a			  =       False
														ctypes.windll.kernelaa.SetConsoleCursorInfo(UpperCamelCase				,		ctypes.byref(UpperCamelCase   )   )
							elif os.name == "posix":
														sys.stdout.write('''\033[?25l'''   )
														sys.stdout.flush()
def 	snake_case_					():





							'''simple docstring'''


							if os.name == "nt":
														_a			  =       CursorInfo()
														_a			  =       ctypes.windll.kernelaa.GetStdHandle(-11   )
														ctypes.windll.kernelaa.GetConsoleCursorInfo(UpperCamelCase				,		ctypes.byref(UpperCamelCase   )   )
														_a			  =       True
														ctypes.windll.kernelaa.SetConsoleCursorInfo(UpperCamelCase				,		ctypes.byref(UpperCamelCase   )   )
							elif os.name == "posix":
														sys.stdout.write('''\033[?25h'''   )
														sys.stdout.flush()

@contextmanager
def 	snake_case_					():





							'''simple docstring'''


							try:
														hide_cursor()
														yield
							finally:
														show_cursor()

