'use strict'

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

  const plus = A + B;
  const minus = A - B;
  let multi = A * B;

  if(Math.abs(multi) === 0) {
    multi = 0;
  } else {
    multi = A * B;
  }

  console.log(Math.max(plus, minus, multi));
}

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