'use strict';
function main(input) {
  input = input.split(" ");
  const p = Number(input[0]) + Number(input[1]);
  const m = Number(input[0]) - Number(input[1]);
  const t = Number(input[0]) * Number(input[1]);

  if(p > m && p > t){
  	console.log(p);
  }else if(m > t){
  	console.log(m);
  }else{
    console.log(t);
  }
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));
