function Main(input) {
    input = input.split(" ");
    
  	var a = Number(input[0]);
	var b = Number(input[1]);
    var ans = a+b;
  	ans = Math.max(a-b, ans);
  	ans = Math.max(a*b, ans);
  
    console.log(ans);
}

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