open System

let (N, K) = 
    let t = Console.ReadLine().Split() |> Array.map int 
    t.[0], t.[1]

let A = Console.ReadLine().Split() |> Array.map int 

A 
|> Array.sortDescending
|> Array.splitAt 1
|> fun (a, b) -> 
    let t = 
        b
        |> Array.truncate K 
        |> Array.where(fun x -> x > 0)
    Array.fold(fun acc x -> acc + x) a.[0] t 
|> printfn "%i"