





from __future__ import annotations

_snake_case  :    Any						    =  {
    'A': ['B', 'C', 'E'],
    'B': ['A', 'D', 'E'],
    'C': ['A', 'F', 'G'],
    'D': ['B'],
    'E': ['A', 'B', 'D'],
    'F': ['C'],
    'G': ['C'],
}



class 				_UpperCAmelCase    :

  """simple docstring"""


  def __init__(				self :		Optional[Any]					,  lowerCAmelCase_ :		dict[str, list[str]]					,  lowerCAmelCase_ :		str     )							->						None:
     __lowerCAmelCase								=	graph
     # mapping node to its parent in resulting breadth first tree
     __lowerCAmelCase								=	{}
     __lowerCAmelCase								=	source_vertex






  def 				lowercase		(				self :		Optional[Any]     )							->						None:
     __lowerCAmelCase								=	{self.source_vertex}
     __lowerCAmelCase								=	None
     __lowerCAmelCase								=	[self.source_vertex]  # first in first out queue

     while queue:
        __lowerCAmelCase								=	queue.pop(0     )
        for adjacent_vertex in self.graph[vertex]:
           if adjacent_vertex not in visited:
              visited.add(lowerCAmelCase_     )
              __lowerCAmelCase								=	vertex
              queue.append(lowerCAmelCase_     )






  def 				lowercase		(				self :		int					,  lowerCAmelCase_ :		str     )							->						str:
     if target_vertex == self.source_vertex:
        return self.source_vertex

     __lowerCAmelCase								=	self.parent.get(lowerCAmelCase_     )
     if target_vertex_parent is None:
        __lowerCAmelCase								=	(
            f"""No path from vertex: {self.source_vertex} to vertex: {target_vertex}"""
        )
        raise ValueError(lowerCAmelCase_     )

     return self.shortest_path(lowerCAmelCase_     ) + f"""->{target_vertex}"""


if __name__ == "__main__":
     _snake_case  :    Dict						    =  Graph(graph, 'G')
     g.breath_first_search()
     print(g.shortest_path('D'))
     print(g.shortest_path('G'))
     print(g.shortest_path('Foo'))








import re

from filelock import FileLock


try:
     import nltk

     _snake_case  :    Any						    =  True
except (ImportError, ModuleNotFoundError):
     _snake_case  :    Union[str, Any]						    =  False

if NLTK_AVAILABLE:
     with FileLock('.lock') as lock:
          nltk.download('punkt', quiet=True)

def   a_    ( lowerCAmelCase_      :			str	):
   re.sub('<n>',	'',	lowerCAmelCase_	)  # remove pegasus newline char
   assert NLTK_AVAILABLE, "nltk must be installed to separate newlines between sentences. (pip install nltk)"
   return "\n".join(nltk.sent_tokenize(lowerCAmelCase_	)	)

