type 'a arbre = Vide | N of 'a arbre * 'a * 'a arbre ;;

let exemple_4 =
 N
  (N (N (N (Vide, 3, Vide), 7, Vide), 9, N (N (Vide, 1, Vide), 5, Vide)), 10,
   N (N (N (Vide, 2, Vide), 6, Vide), 8, N (N (Vide, 0, Vide), 4, Vide)))
and exemple_5 =
 N
  (N (N (N (Vide, 7, Vide), 3, Vide), 9, N (N (Vide, 1, Vide), 5, Vide)), 10,
   N (N (N (Vide, 2, Vide), 6, Vide), 8, N (N (Vide, 0, Vide), 4, Vide)))
and exemple_6 =
 N
  (N
    (N (N (N (Vide, 3, Vide), 7, Vide), 9, N (N (Vide, 1, Vide), 5, Vide)),
     10,
     N (N (N (Vide, 2, Vide), 6, Vide), 8, N (N (Vide, 0, Vide), 4, Vide))),
   11, N (Vide, 3, Vide))
and exemple_7 =
 N
  (N
    (N (N (Vide, 4, Vide), 8, N (Vide, 0, Vide)), 10,
     N (N (Vide, 2, Vide), 6, Vide)),
   11, N (N (N (Vide, 3, Vide), 7, Vide), 9, N (N (Vide, 1, Vide), 5, Vide)))
and exemple_8 =
 N
  (N
    (N (N (Vide, -1, Vide), 4, N (Vide, 0, Vide)), 8,
     N (N (Vide, 2, Vide), 6, Vide)),
   10, N (N (N (Vide, 3, Vide), 7, Vide), 9, N (N (Vide, 1, Vide), 5, Vide)))
;;