function turn(kk){
		
		
		 
		 		
		  		var Ta;
				var trun_button;
				var show_window;
				var li;
				show_window=document.getElementById("show_window");
				trun_button=document.getElementById("trun_button");
				Ta=trun_button.getElementsByTagName("a");
				 
				
				for(var i=0;i<Ta.length;i++){
					if(i==kk){
						Ta[i].className="select";
						li=show_window.getElementsByTagName("li");
						li[i].style.display=""
					}else{
				Ta[i].className="";
				li=show_window.getElementsByTagName("li");
				li[i].style.display="none"
					}
				}
				
	}		 var n=0;
				function clearAuto(){clearInterval(autoStart)}
				function setAuto(){autoStart=setInterval("auto(n)", 2500)}
				function auto(){
					n++;
					if(n>3)n=0;
					turn(n);
				} 
				setAuto();