let rec even : int -> (bool -> bool) -> bool = fun n : int -> fun k : (bool -> bool) ->
    if n = 0 then
        k true
    else
        odd (n - 1) k
and odd : int -> (bool -> bool) -> bool = fun n : int -> fun k : (bool -> bool) ->
    if n = 0 then
        k false
    else
        even (n - 1) k
in
let empty_k : bool -> bool = fun k : bool -> k in

let n : int = read_int () in
print_bool (even n empty_k)
