object Main{
 
def main(args: Array[String]): Unit = {
  
    val arr1 = io.StdIn.readLine().split(' ')
    val a = arr1(0).toInt
  val b = arr1(1).toInt
  
  val ab = a * b
  val ap = a + b
  val am = a - b
  
  val arr = Array(ab, ap, am)
  
  println(arr.max)
}
}