import scala.io.StdIn.readLine

object Main extends App {
  val input = readLine().split(" ").map(_.toInt)
  val a = input(0)
  val b = input(1)

  val sum = a + b
  val difference = a - b
  val product = a * b

  val list = List(sum, difference, product)
  val ans = list.max

  println(ans)
}