var how_many_ads = 3;   
var now = new Date()
var sec = now.getSeconds()
var ad = sec % how_many_ads;
ad +=1;
//alert(ad);
if (ad==1) {
document.write("<iframe id='neirong' name='neirong' width="+w+" height="+h+" frameborder=0 scrolling=no src=http://y.abang.com/z/bd/"+x+"-1.htm></iframe>");
}
else if (ad==2) {
document.write("<iframe id='neirong' name='neirong' width="+w+" height="+h+" frameborder=0 scrolling=no src=http://y.abang.com/z/bd/"+x+"-2.htm></iframe>");
}
else {
document.write("<iframe id='neirong' name='neirong' width="+w+" height="+h+" frameborder=0 scrolling=no src=http://y.abang.com/z/bd/"+x+"-3.htm></iframe>");
}