Banner-rotator mit mt_rand

<?php
$Img1 = "/banner/TASK-one.png";
$Url1 = "http://www.TASK-one.tld";
$Alt1 = "TASK-one";

$Img2 = "/banner/TASK-two.png";
$Url2 = "http://www.TASK-two.tld";
$Alt2 = "TASK-two";

$num = mt_rand (1,2);

$Image = ${'Img'.$num};
$URL = ${'Url'.$num};
$Alt = ${'Alt'.$num};

Print "<a href=\"".$URL."\" target=\"_blank\"><img src=\"".$Image."\" alt=\"".$Alt."\" height=\"68\" width=\"300\" border=\"0\" /></a>";
?>