function changTab(getId, getClass, num, cho){
		//changTab('bbs1','menu1',1,'tab_list_');
		var obj = document.getElementById(getId);
		obj.className = getClass;
		for(i=1;i<3;i++){
			var ddd = cho + i;
			if(i == num) {
				document.getElementById(ddd).style.display = "block";
			} else {
				document.getElementById(ddd).style.display = "none";
			}
		}
	}