Scanf.scanf "%d" (fun n ->
    let c = Array.init n (fun _ -> Scanf.scanf " %d" (fun c -> c)) in
    let s = Array.fold_left (+) 0 c in

    let rec loop i sum =
        if i = n then sum else
            if c.(i) * 10 <= s then loop (i + 1) (sum + 30)
            else loop (i + 1) sum
    in
    loop 0 0 |> Printf.printf "%d\n"
)