Scanf.scanf "%d" (fun n ->
    let a = Array.make 192 0 in

    let rec loop i j =
        if i < 10 then (a.(j) <- i; loop (i + 1) (j + 1)) else
        if i < 100 then (
            a.(j) <- i / 10;
            a.(j + 1) <- i mod 10;
            loop (i + 1) (j + 2)
        ) else (
            a.(j) <- 1
        )
    in
    loop 1 2;

    let b = Array.make 192 0 in

    let rec loop i carry =
        if i >= 0 then
            let c = a.(i) * n + carry in
            let () = b.(i) <- c mod 10 in
            loop (i - 1) (c / 10)
    in
    loop 191 0;
    Printf.printf "%d." (b.(0) * 10 + b.(1));
    for i = 2 to 191 do
        Printf.printf "%d" b.(i)
    done;
    print_newline ()
)