stdin.ReadLine().Split(" ")
|> Array.map int
|> fun x ->
    let d = x |> Array.rev |> Array.head
    x
    |> Array.take 3
    |> Array.sort
    |> fun [| a; b; c |] ->
        if c - b <= d && b - a <= d then "Yes" else "No"
        |> printfn "%s"
