let delete_node_by n p =
if n.deleted then
begin
fprintf !dot_fmt "%d [color=\"blue\"]@." n.tag;
(* (hex_color !current_color); *)
(* if Node.has_deleted_ancestor n then match n.from with *)
(* | (_,_,p)::_ -> *)
fprintf !dot_fmt "%d -> %d [penwidth=2, color=blue, style=dashed, constraint=false, arrowhead=onormal]"
n.tag p.tag
(* | _ -> () *)
(* fprintf !dot_fmt "%d -> %d [style=dashed, constraint=false]" s.tag n.tag *)
end