public static void main(String args[])
	{
		Digraph G = null;
		try
		{
			G = new Digraph(new In(args[0]));
			System.out.println(args[0] + "\n" + G);

		}
		catch (Exception e)
		{
			System.out.println(e);
			System.exit(1);
		}

		OrderDirectedDFS order = new OrderDirectedDFS(G);

		System.out.println("Post order of G");
		for (int v : order.postOrder())
			System.out.print(v + " ");

		OrderDirectedDFS reverse = new OrderDirectedDFS(G.reverse());
		System.out.println("\nReverse post order of R");
		for (int v : reverse.reversePostOrder())
			System.out.print(v + " ");

	}