Working on it more. :(

go/pov/cmd/main.go

@@ -1,13 +1,26 @@
 package main
 
-import pov ".."
+import (
+	"fmt"
+
+	pov ".."
+)
 
 func main() {
 	g := pov.New()
-	g.AddNode("sibling")
-	g.AddNode("x")
 	g.AddNode("parent")
-	g.AddArc("parent", "sibling")
 	g.AddArc("parent", "x")
+	g.AddArc("x", "sib-2")
+	g.AddArc("x", "sib-3")
+	g.AddArc("x", "sib-4")
+	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)
+	fmt.Println("== Change Root to child-3 ==")
+	n := g.ChangeRoot("parent", "child-3")
+	pov.PrintGraph(n)
 }