const main = (input) => {
  const args = input.split(' ');
  const A = parseInt(args[0], 10);
  const B = parseInt(args[1], 10);

  const sumNum = A+B
  const minusNum = A-B
  const doubleNum = A*B

  const result = Math.max(sumNum, minusNum, doubleNum)

  console.log(result) 

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