track = new Array();
function opencity(name) {
	//alert(name);
	o = document.getElementById(name);
	if (track[name]==1) {
		o.style.position='absolute';
		o.style.visibility='hidden';
		track[name]=0;
	} else {
		o.style.position='relative';
		o.style.visibility='visible';
		track[name]=1;
	}
}	
function openall() {
//alert(1);
for (var i in track) {
		//alert(i);
		if (track[i]==0) opencity(i);
	} 
}