function Main(input) {
  input = input.trim()
 input = input.split(" ").map(Number);
var arr=[];
arr.push(input[0]+input[1])
arr.push(input[0]-input[1])
arr.push(input[0]*input[1])
console.log(Math.max.apply(null, arr))
}Main(require("fs").readFileSync("/dev/stdin", "utf8"));