'use strict'

function main(s) {

  s = s.split('\n')[0].split(' ');
  const A = Number(s[0]);
  const B = Number(s[1]);
  const sum = Math.max(...[A + B, A - B, A * B]);
  console.log(sum);

}

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