open Scanf
open Printf

let rint () = scanf " %d" (fun x -> x)
let stoa s = Array.init (String.length s) (String.get s)
let atos a = String.init (Array.length a) (Array.get a)

let () =
  let a = rint() and b = rint() in
  printf "%d\n" (max (a + b) (max (a - b) (a * b)))