Scanf.scanf "%d %d %d %s" (fun n k c s ->
    let forward = Array.make k 0 in
    let reverse = Array.make k 0 in
    let rec loop cur i =
        if cur = k then () else
            if s.[i] = 'o' then (forward.(cur) <- i; loop (cur + 1) (i + c + 1))
                           else loop cur (i + 1)
    in
    loop 0 0;

    let rec loop cur i =
        if cur < 0 then ()  else
            if s.[i] = 'o' then (reverse.(cur) <- i; loop (cur - 1) (i - c - 1))
                           else loop cur (i - 1)
    in
    loop (k - 1) (n - 1);
    for i = 0 to k - 1 do
        if forward.(i) = reverse.(i) then Printf.printf "%d\n" @@ forward.(i) + 1
    done
)