Scanf.scanf "%d" (fun n ->
    let a = Array.init (n - 1) (fun _ -> Scanf.scanf " %d" (fun d -> d)) in
    let sum = Array.fold_left (+) 0 a in
    let rec loop i acc =
        if i > 100 then acc else
            loop (i + 1) (if (sum + i) mod n = 0 then acc + 1 else acc)
    in
    loop 0 0 |> Printf.printf "%d\n"
)