today=new Date();
jran=today.getTime();

function rnd() {

    ia=9301;
    ic=49297;
    im=233280;

    jran = (jran*ia+ic) % im;
    return jran/(im*1.0);
};

function rand(number) {

    return Math.ceil(rnd()*number);
};


for(i=1;i<=1;i++) {
    myNum=(rand(1)); //改成你要随机显示的图片数；
   if(myNum == 1) document.write("<a href='http://see.cartoonwin.com/php/shop/unit.php?cat=5&uni=201' target='_blank'><img src=http://www.cartoonwin.com/ads/xiju.gif border=0></a>");
 
 //图片路径，可用http://

   else {
document.write();
}

};