Changing it into a graph

Since that's what they actually want, even though the exercise says it's
a tree

go/pov/cmd/main.go

@@ -8,19 +8,13 @@ import (
 
 func main() {
 	g := pov.New()
-	g.AddNode("parent")
-	g.AddArc("parent", "x")
-	g.AddArc("x", "sib-2")
-	g.AddArc("x", "sib-3")
-	g.AddArc("x", "sib-4")
+	g.AddNode("sibling")
+	g.AddNode("x")
 	g.AddArc("parent", "sibling")
-	g.AddArc("sibling", "child-1")
-	g.AddArc("sibling", "child-2")
-	g.AddArc("sibling", "child-3")
-	g.AddArc("child-3", "grandchild-1")
-	g.AddArc("grandchild-1", "greatgrandchild-1")
-	pov.PrintGraph(g)
+	g.AddArc("parent", "x")
 	fmt.Println("== Change Root to child-3 ==")
-	n := g.ChangeRoot("parent", "child-3")
-	pov.PrintGraph(n)
+	g.Print("parent")
+	n := g.ChangeRoot("parent", "x")
+	fmt.Println(n.ArcList())
+	g.Print("x")
 }