var lastvisible=[];

function swapVisibility(arrayname,arrayindex) {
var w=document.getElementById(arrayname+arrayindex);
if(w) {
	if(arrayname in lastvisible) lastvisible[arrayname].style.display='none';
	w.style.display='block';
	lastvisible[arrayname]=w;
}
}
function setVisible(arrayname,arrayindex) { 
var w=document.getElementById(arrayname+arrayindex);
if(w) lastvisible[arrayname]=w;
}

var lastclass=[];

function swapClass(arrayname,arrayindex,activeclass,nonactiveclass) {
var w=document.getElementById(arrayname+arrayindex);
if(w) {
	if(arrayname in lastclass) lastclass[arrayname].className=nonactiveclass;
	w.className=activeclass;
	lastclass[arrayname]=w;
}
}