'use strict';

function Main(INPUT) {
    const N = INPUT.split(" ").map(n => Number(n));
    let ans = Math.max(N[0] + N[1], N[0] - N[1], N[0] * N[1]);
    if (ans === -0) ans = 0;
    console.log(ans);
}

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