private void DFS(Digraph g, int v)
{
_pre.Enqueue(v);
_marked[v] = true;
foreach (var w in g.Adjacent(v))
{
if (!_marked[w])
{
DFS(g, w);
}
}
_post.Enqueue(v);
_reversePost.Push(v);
}
public static double AverageDegreeOut(Digraph g)
{
return((double)g.E / g.V);
}