(* O(n log n) *)
let n, k = Scanf.scanf " %d %d" @@ fun a b -> a, b
let a_s = Array.init n @@ fun _ -> Scanf.scanf " %d" @@ (+) 0
let rec gcd a b = if b = 0 then a else gcd b (a mod b)
let g = Array.fold_left gcd 0 a_s
let _ =
  Array.iter (fun a -> if a >= k && (a - k) mod g = 0 then (print_endline "POSSIBLE"; exit 0)) a_s;
  print_endline "IMPOSSIBLE"