
open Scanf
open Printf

let flip f x y = f y x

let rec range a b = if a >= b then [] else a :: range (a+1) b

let read_int () = scanf " %d" (fun x -> x)
let rec read_ints n = if n = 0 then [] else let i = read_int () in i :: read_ints (n-1)

let rec for_iter a b f = if a >= b then [] else let x = f a in x :: for_iter (a+1) b f
let rec for_iter_ a b f = if a >= b then () else (f a; for_iter_ (a+1) b f)

module IntSet = Set.Make(struct
  type t = int
  let compare = (-)
end)

let () =
  let n = read_int () in
  let xs = read_ints n in
  List.fold_left (fun s x ->
    if IntSet.mem x s then IntSet.remove x s else IntSet.add x s)
  IntSet.empty xs
  |> IntSet.elements |> List.length
  |> printf "%d\n"
