function SelClass(id,k,n,clsa,clsb)
{
	for(i=1;i<=n;i++)
	{
		if (i==k)
		{
		 document.getElementById(id+i).className =clsb;
		 document.getElementById(id+"x"+i).style.display ="block";
		}
	   else
	   {
		 document.getElementById(id+i).className =clsa;
		 document.getElementById(id+"x"+i).style.display ="none";
	   }
	}

}