(* O(n) *)
open Hashtbl
let n = Scanf.scanf " %d" @@ (+) 0
let a_s = Array.init n @@ fun _ -> Scanf.scanf " %d" @@ (+) 0
let h = create n
let _ =
  Array.iter (fun a -> try let c = find h a in replace h a @@ c + 1 with _ -> add h a 1) a_s;
  fold (fun _ c acc -> acc + if c mod 2 = 0 then 0 else 1) h 0 |> Printf.printf "%d\n"