var curIndex=0;
var caaIndex=0;
var timeInterval=3000;
var arr=new Array();
arr[0]="images/chengge2.gif";
arr[1]="images/chengge3.gif";
arr[2]="images/chengge.gif";
var brr=new Array();
brr[0]="../case/case_product_sigao.html";
brr[1]="../case/case_product_canada.html";
brr[2]="../case/case_meeting_education.html";
setInterval(changeImg,timeInterval);
function changeImg()
{
    var obj=document.getElementById("obj");
    var oaa=document.getElementById("aaa");
    if (curIndex==arr.length-1)
    {
        curIndex=0;
        caaIndex=0;
    }
    else
    {
        curIndex+=1;
        caaIndex+=1;
    }
    obj.src=arr[curIndex];
    oaa.href=brr[caaIndex];
}