function hot(obj){
 	var h=document.getElementById("title").getElementsByTagName("span");;
	var d=document.getElementById("showdiv").getElementsByTagName("div");
	for(var i=0;i<h.length;i++){
		if(obj-1==i){
			h[i].className="hot";
			d[i].className="block";
		}else {
			h[i].className="out";
			d[i].className="none";
		}
	}
}