Scanf.scanf "%d %d %d" (fun x y l ->
    let ll k = (abs k + l - 1) / l in
    Printf.printf "%d\n" @@
    ll x + ll y + match y >= 0, x = 0 with
    | true,  true  -> 0
    | true,  false -> 1
    | false, _     -> 2
)