程序代码：

<script language="javascript"> 
rnd.today=new Date(); 
rnd.seed=rnd.today.getTime(); 
function rnd() 
{ 
rnd.seed=(rnd.seed*9301+49297) % 233280; 
return rnd.seed/(233280.0); 
} 
function rand(number) 
{ 
return Math.ceil(rnd()*number); 
} 
if (navigator.userAgent.indexOf('Safari') != -1) 
{ 
var pagenumber = front1.length -1 ; 
var randomnumber = Math.random() ; 
var rand1 = rand(pagenumber); 
document.write(front1[rand1][2]); 
} 
else 
{ 
var pagenumber = front.length -1 ; 
var randomnumber = Math.random() ; 
var rand1 = rand(pagenumber); 
document.write(front[rand1][2]); 
} 
</script>