Submission #122467

---

Source Code Expand

let id x = x
let ( |> ) x f = f x
let (n, k) = Scanf.scanf "%d %d\n" (fun n k -> (n, k))

let repeat f =
  let rec loop acc = function
    | 0 -> List.rev acc
    | n -> loop (f () :: acc) (n - 1) in
  loop []

let r = repeat (fun () -> Scanf.scanf "%d " id) n

let rec take n = function
  | [] -> []
  | hd :: tl ->
      if n = 0 then []
      else hd :: take (n - 1) tl

let () =
  r 
    |> List.sort compare
    |> List.rev
    |> take k
    |> List.rev
    |> List.map float_of_int
    |> List.fold_left (fun c r -> (c +. r) /. 2.) 0.
    |> Printf.printf "%f\n"

Submission Info

Judge Result