import java.util.*

fun main(args: Array<String>) {
    val argList = Scanner(System.`in`)

    val line = argList.nextLine().split(" ")
    val a = line[0].toInt()
    val b = line[1].toInt()

    val e = PlusMinusX()
    println(e.execute(a, b))

}

class PlusMinusX {
    fun execute(a: Int, b: Int): Int? {
        val plus = a + b
        val minux = a - b
        val multiple = a * b

        return listOf(plus, minux, multiple).max()
    }
}