随机显示广告代码

<SCRIPT LANGUAGE="JavaScript">
<!--
shu =7

ad1='<br>'

//////// 广告内容

theAds = new Array();

theAds[1] = "广告代码1";
theAds[2] = "广告代码2";
theAds[3] = "广告代码3";
theAds[4] = "广告代码4";
theAds[5] = "广告代码5";
theAds[6] = "广告代码6";
theAds[7] = "广告代码7";

sx = parseInt(Math.random() * shu + 1);
document.write(ad1+theAds[sx]);
--></SCRIPT>