public void WriteChildren (int level) {
for (int i=0;i<level;i++) {
Console.Write (" ");
}
if (node != null) {
Console.WriteLine ("Leaf ");//+triangle.ToString ());
} else {
Console.WriteLine ("Box ");//+rect.ToString ());
c1.WriteChildren (level+1);
c2.WriteChildren (level+1);
}
}
}