function rotation(obj,index) {
me=eval(obj);
me[index].style.display="none"
index++;
if(index==me.length)index=0;
me[index].style.display="block"
setTimeout("rotation('"+obj+"',"+index+")",5000);
}
window.onload=function(){
obj2=document.getElementsByClassName("ban2");rotation("obj2",0);
}