type tree = Nil | Node of int * tree * tree

let create () = Nil

let insert x t =
  let rec doit = function
    | Nil -> Node (x, Nil, Nil)
    | Node (y, l, r) when x < y -> Node (y, doit l, r)
    | Node (y, l, r) -> Node (y, l, doit r)
  in doit t

let preorder f t =
  let rec doit = function
    | Nil -> ()
    | Node (x, l, r) -> (f x; doit l; doit r)
  in doit t

let inorder f t =
  let rec doit = function
    | Nil -> ()
    | Node (x, l, r) -> (doit l; f x; doit r)
  in doit t

let print t =
  let f e = print_string " "; print_int e in
  inorder f t;
  print_newline ();
  preorder f t;
  print_newline ()

let find x t =
  let rec doit = function
    | Nil -> false
    | Node (y, _, _) when x = y -> true
    | Node (y, l, _) when x < y -> doit l
    | Node (_, _, r) -> doit r
  in doit t

let delete x t =
  let rec dudu = function
    | Nil -> exit 1
    | Node (x, Nil, _) -> x
    | Node (_, l, _) -> dudu l
  and wa = function
    | Nil -> exit 1
    | Node (_, Nil, r) -> r
    | Node (x, l, r) -> Node (x, wa l, r)
  and doit = function
    | Nil -> exit 1
    | Node (y, l, r) when x = y ->
      if l = Nil then r
      else if r = Nil then l
      else Node (dudu r, l, wa r)
    | Node (y, l, r) when x < y -> Node (y, doit l, r)
    | Node (y, l, r) -> Node (y, l, doit r)
  in doit t

let split str delim =
  let open String in
  let rec doit s acc =
    match
      try Some (rindex s delim) with _ -> None
    with
    | None -> s :: acc
    | Some i ->
      let s1 = sub s 0 i in
      doit s1 (sub s (i + 1) (length s - length s1 - 1) :: acc)
  in doit str []

let () =
  let m = read_int () in
  let rec read i t =
    if i < m then begin
      match split (read_line ()) ' ' with
      | ["insert"; n] -> read (i + 1) (insert (int_of_string n) t)
      | ["find"; n] -> (print_endline (if find (int_of_string n) t then "yes" else "no"); read (i + 1) t)
      | ["delete"; n] -> read (i + 1) (delete (int_of_string n) t)
      | _ -> (print t; read (i + 1) t)
    end in
  read 0 (create ())