text: from networkx.utils import reverse_cuthill_mckee_ordering
  import networkx as nx
  
  
  def test_reverse_cuthill_mckee():
      # example graph from
      # http://www.boost.org/doc/libs/1_37_0/libs/graph/example/cuthill_mckee_ordering.cpp
      G = nx.Graph([(0, 3), (0, 5), (1, 2), (1, 4), (1, 6), (1, 9), (2, 3),
                    (2, 4), (3, 5), (3, 8), (4, 6), (5, 6), (5, 7), (6, 7)])
      rcm = list(reverse_cuthill_mckee_ordering(G))
      assert rcm in [[0, 8, 5, 7, 3, 6, 2, 4, 1, 9],
                     [0, 8, 5, 7, 3, 6, 4, 2, 1, 9]]
  
  
  def test_rcm_alternate_heuristic():
      # example from
      G = nx.Graph([(0, 0),
                    (0, 4),
                    (1, 1),
                    (1, 2),
                    (1, 5),
                    (1, 7),
                    (2, 2),
                    (2, 4),
                    (3, 3),
                    (3, 6),
                    (4, 4),
                    (5, 5),
                    (5, 7),
                    (6, 6),
                    (7, 7)])
  
      answers = [[6, 3, 5, 7, 1, 2, 4, 0], [6, 3, 7, 5, 1, 2, 4, 0],
                 [7, 5, 1, 2, 4, 0, 6, 3]]
  
      def smallest_degree(G):
          deg, node = min((d, n) for n, d in G.degree())
          return node
      rcm = list(reverse_cuthill_mckee_ordering(G, heuristic=smallest_degree))
      assert rcm in answers
  