public DepthFirstOrder(Digraph g)
{
pre = new Queue <int>();
post = new Queue <int>();
reversePost = new Stack <int>();
marked = new bool[g.V];
for (int v = 0; v < g.V; v++)
{
if (!marked[v])
{
DFS(g, v);
}
}
}
/**
* Returns the reverse of the digraph.
*
* @return the reverse of the digraph
*/
public Digraph <T> reverse()
{
Digraph <T> reverse = new Digraph <T>();
foreach (T v in Vertices)
{
object nv = v.Clone();
}
foreach (T v in Vertices)
{
foreach (T s in Successors(v))
{
reverse.AddEdge(new DirectedEdge <T>(s, v));
}
}
return(reverse);
}
/**
* Returns the reverse of the digraph.
*
* @return the reverse of the digraph
*/
public Digraph <T> reverse()
{
Digraph <T> reverse = new Digraph <T>();
foreach (var v in this.Vertices)
{
var nv = v.Clone();
}
foreach (var v in this.Vertices)
{
foreach (var s in this.Successors(v))
{
reverse.AddEdge(new DirectedEdge <T>(s, v));
}
}
return(reverse);
}
public DirectedDFS(Digraph g, int s)
{
marked = new bool[g.V];
DFS(g, s);
}
/**
* Unit tests the {@code DepthFirstOrder} data type.
*
* @param args the command-line arguments
*/
public static void test()
{
string tiny = $@"
13
22
4 2
2 3
3 2
6 0
0 1
2 0
11 12
12 9
9 10
9 11
7 9
10 12
11 4
4 3
3 5
6 8
8 6
5 4
0 5
6 4
6 9
7 6
";
Digraph <IntWrapper> G = new Digraph <IntWrapper>(tiny, (string s) => new IntWrapper(int.Parse(s)));
System.Console.Error.WriteLine(G);
DepthFirstOrder <IntWrapper, DirectedEdge <IntWrapper> > dfs = new DepthFirstOrder <IntWrapper, DirectedEdge <IntWrapper> >(G);
System.Console.WriteLine(" v pre post");
System.Console.WriteLine("--------------");
foreach (var v in G.Vertices)
{
System.Console.Write("{0} {1} {2}\n", v, dfs.Pre(v), dfs.Post(v));
}
System.Console.Write("Preorder: ");
foreach (IntWrapper v in dfs.Pre())
{
System.Console.Write(v + " ");
}
System.Console.WriteLine();
System.Console.Write("Postorder: ");
foreach (IntWrapper v in dfs.Post())
{
System.Console.Write(v + " ");
}
System.Console.WriteLine();
System.Console.Write("Reverse postorder: ");
foreach (IntWrapper v in dfs.reversePost())
{
System.Console.Write(v + " ");
}
System.Console.WriteLine();
}
