function Main(input) {
	input = input.trim().split(" ").map((a)=>Number(a));
  var A = input[0];
  var B = input[1];
  var list = [A+B,A-B,A*B];
  console.log(Math.max.apply(null,list));
}

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