@NotNull
  public static List<Integer> getDownNodes(@NotNull LinearGraph graph, final int nodeIndex) {
    return ContainerUtil.mapNotNull(graph.getAdjacentEdges(nodeIndex, EdgeFilter.NORMAL_DOWN), graphEdge -> graphEdge.getDownNodeIndex());
  }
@NotNull
  public static List<Integer> getDownNodes(@NotNull LinearGraph graph, final int nodeIndex)