[<AutoOpen>]
module Program

open System

let read f = stdin.ReadLine() |> f
let reads f = stdin.ReadLine().Split() |> Array.toList |> List.map f

[<EntryPoint>]
let main _ =
    let [a;b] = reads int
    [
        a + b
        a - b
        a * b
    ]
    |> List.max
    |> printfn "%i"
    0