function Check(a,b) {
  if (a % 3 == 0 || b % 3 == 0 || (a+b)%3 == 0){
    return 'Possible';
  }
  return 'Impossible';
}

function Main(input) {

  input = input.split("\n");
  tmp = input[0].split(" ");

  var a = parseInt(tmp[0], 10);
  var b = parseInt(tmp[1], 10);

  console.log(,Check(a,b));
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));

