let R    ()  = stdin.ReadLine() |> int64
let Work W D = W / (D * D)

let W = R ()
let D = R ()

(W,D) 
|> Array.unfold(fun (w,d) ->
        match d with
        | 0L ->
            None
        | d  ->
            let dayWork  = Work w d
            let leftWork = w - dayWork
            let leftDay  = d - 1L
            Some(dayWork,(leftWork,leftDay)))
|> Array.last
|> printfn "%i"