var n = 0;
var imgs = new Array(4);//图片名称
var imgurl="../img/"
	imgs[0]=imgurl+ "1.jpg";
	imgs[1]=imgurl+  "2.jpg";
	imgs[2]=imgurl+  "3.jpg";
	imgs[3]=imgurl+  "4.jpg";
var timer
function showAd(){
		var myimg = document.getElementById("adimg");
		var imglink = document.getElementById("mylink");
		myimg.setAttribute("src",imgs[n]);
		
		var mylist = document.getElementById("myul").getElementsByTagName("li");
		var mylink = document.getElementById("myul").getElementsByTagName("a");
		var links = mylink[n].getAttribute("href");
		var titles = mylink[n].getAttribute("title");
		imglink.setAttribute("href",links);
		imglink.setAttribute("alt",titles);
		for(i=0;i<mylist.length;i++)
		{
			mylist[i].className = "none";
			mylink[i].className = "none";
			
		}
		mylist[n].className="over";
		mylink[n].className="over";
		n++;
		if(n==4) n=0;
}
function showme(){clearInterval(timer);showAd()}
function showall(){timer=setInterval("showAd()",3000);}
timer=setInterval("showAd()",3000);