



'''simple docstring'''





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





def   a_   (		_UpperCAmelCase    :      str				)    ->  str:
      if not head or not head.next:
            return True

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

      # 2. Push the second half into the stack
      __snake_case :   Optional[int]													=    [slow.val]
      while slow.next:
            __snake_case :   List[str]													=    slow.next
            stack.append(slow.val				)

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

      return True





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








'''simple docstring'''





from typing import TYPE_CHECKING

# rely on isort to merge the imports
from ...utils import OptionalDependencyNotAvailable, _LazyModule, is_torch_available


A__    :   List[str]           =					{
    '''configuration_autoformer''': [
        '''AUTOFORMER_PRETRAINED_CONFIG_ARCHIVE_MAP''',
        '''AutoformerConfig''',
    ],
}

try:
    if not is_torch_available():
        raise OptionalDependencyNotAvailable()
except OptionalDependencyNotAvailable:
    pass
else:
    A__    :   Optional[Any]           =					[
        '''AUTOFORMER_PRETRAINED_MODEL_ARCHIVE_LIST''',
        '''AutoformerForPrediction''',
        '''AutoformerModel''',
        '''AutoformerPreTrainedModel''',
    ]


if TYPE_CHECKING:
    from .configuration_autoformer import (
        AUTOFORMER_PRETRAINED_CONFIG_ARCHIVE_MAP,
        AutoformerConfig,
    )

    try:
        if not is_torch_available():
            raise OptionalDependencyNotAvailable()
    except OptionalDependencyNotAvailable:
        pass
    else:
        from .modeling_autoformer import (
            AUTOFORMER_PRETRAINED_MODEL_ARCHIVE_LIST,
            AutoformerForPrediction,
            AutoformerModel,
            AutoformerPreTrainedModel,
        )

else:
    import sys

    A__    :   Optional[int]           =					_LazyModule(__name__, globals()['''__file__'''], _import_structure, module_spec=__spec__)



