Scanf.scanf "%d %d" (fun n k ->
    let p = Array.init n (fun _ -> Scanf.scanf " %d" (fun p -> p)) in
    let module S = Set.Make (struct type t = int let compare = compare end) in

    let grp = Array.make n 0 in

    let rec loop i prev cur =
        if i = n then () else
            let cur = if p.(i) > prev then cur else cur + 1 in
            let () = grp.(i) <- cur in
            loop (i + 1) p.(i) cur
    in
    loop 1 p.(0) 0;

    let par = Array.init (n - k + 2) (fun i -> i) in
    let rec root x =
        if x = par.(x) then x else
            let r = root par.(x) in
            let () = par.(x) <- r in
            r
    in
    let merge a b =
        if root a <> root b then par.(par.(b)) <- par.(a)
    in

    let e = n - k + 1 in

    let rec loop i set =
        if i + k = n then (
            if grp.(i) = grp.(i + k - 1) then merge i e
        ) else
            let cmi = S.min_elt set in
            let cmx = S.max_elt set in
            let set = S.remove p.(i) set in
            let set = S.add p.(i + k) set in
            let nmi = S.min_elt set in
            let nmx = S.max_elt set in

            if grp.(i) = grp.(i + k - 1) then (
                merge i e;
                loop (i + 1) set
            ) else (
                if cmi = nmi && cmx = nmx then merge i (i + 1);
                loop (i + 1) set
            )
    in
    let init =
        let rec loop i set =
            if i = k then set else loop (i + 1) (S.add p.(i) set)
        in
        loop 0 S.empty
    in
    loop 0 init;
    let rec loop i set =
        if i + k > n then S.cardinal set else
            loop (i + 1) (S.add (root i) set)
    in
    loop 0 S.empty |> Printf.printf "%d\n"
)