def 			__SCREAMING_SNAKE_CASE						(      __UpperCamelCase					: dict			)							->      set:







  """simple docstring"""





  SCREAMING_SNAKE_CASE__    							=   set()
  # edges = list of graph's edges
  SCREAMING_SNAKE_CASE__    							=   get_edges(__UpperCamelCase			)

  # While there are still elements in edges list, take an arbitrary edge
  # (from_node, to_node) and add his extremity to chosen_vertices and then
  # remove all arcs adjacent to the from_node and to_node
  while edges:
    SCREAMING_SNAKE_CASE__							,  SCREAMING_SNAKE_CASE__    							=   edges.pop()
    chosen_vertices.add(__UpperCamelCase			)
    chosen_vertices.add(__UpperCamelCase			)
    for edge in edges.copy():
      if from_node in edge or to_node in edge:
        edges.discard(__UpperCamelCase			)
  return chosen_vertices



def 			__SCREAMING_SNAKE_CASE						(      __UpperCamelCase					: dict			)							->      set:







  """simple docstring"""





  SCREAMING_SNAKE_CASE__    							=   set()
  for from_node, to_nodes in graph.items():
    for to_node in to_nodes:
      edges.add((from_node, to_node)			)
  return edges


if __name__ == "__main__":
   import doctest

   doctest.testmod()

   # graph = {0: [1, 3], 1: [0, 3], 2: [0, 3, 4], 3: [0, 1, 2], 4: [2, 3]}
   # print(f"Matching vertex cover:\n{matching_min_vertex_cover(graph)}")

from math import isqrt



def 			__SCREAMING_SNAKE_CASE						(      __UpperCamelCase					: int			)							->      bool:







  """simple docstring"""





  return all(number % divisor != 0 for divisor in range(2				,  isqrt(__UpperCamelCase			) + 1			)			)



def 			__SCREAMING_SNAKE_CASE						(      __UpperCamelCase					: int = 10**6			)							->      int:







  """simple docstring"""





  SCREAMING_SNAKE_CASE__    							=   0
  SCREAMING_SNAKE_CASE__    							=   1
  SCREAMING_SNAKE_CASE__    							=   7
  while prime_candidate < max_prime:
    primes_count += is_prime(__UpperCamelCase			)

    cube_index += 1
    prime_candidate += 6 * cube_index

  return primes_count


if __name__ == "__main__":
   print(F"""{solution() = }""")
