function change_con(ww,num,hh)
{
	var obj=ww
	for(var ii=1;ii<=num;ii++)
	{
		document.getElementById(obj+ii).className=obj+"_off";
		document.getElementById(obj+ii+ii).style.display="none";
	}
	document.getElementById(obj+hh).className=obj+"_on";
	document.getElementById(obj+hh+hh).style.display="";
}