function main(input) {
    input = input.split('\n');
    const args = input[0].split(' ');
    let A = parseInt(args[0]);
    let B = parseInt(args[1]);
    let ans = Math.max(A + B, A - B, A * B);
    if (ans === -0) ans = 0;
    console.log(ans);
}

main(require('fs').readFileSync('/dev/stdin', 'utf-8'));
