'use strict'

function Main(input) {
  const A = Number(input.split(" ")[0])
  const B = Number(input.split(" ")[1])

  const add = A + B
  const diff = A - B
  const cross = A * B

  console.log(Math.max(add, diff, cross))

}
Main(require("fs").readFileSync("/dev/stdin", "utf8").trim())