PHP date question

Ok I can echo "Hello World!" but the problem is that after 30 minutes it should only echo "Hello you loser!"
How do I do this?


<?php
if (isset($_COOKIE['time'])) {
      print (time() > ($_COOKIE['time'] + 30 * 60))
                    ? "Hello you loser!" : "Hello World!";
}
else {
    setcookie('time', time());
    print "Hello World!";
}
?>