'use strict';

function main(input) {
  console.log(input);
  const args = input.split('');

  const a = parseInt(args[0], 10);
  const b = parseInt(args[1], 10);

  const add = a + b;
  const sub = a - b;
  const mul = a * b;

  if(add > sub  && add > mul){
    const max = add;
  }else if(sub > add && sub > mul){
    const max = sub;
  }else
  {
    const max = mul;
  }
  console.log(max);
}

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