dom = (document.getElementById)?1:0;
ns4 = (document.layers)?1:0;
ie = (document.all)?1:0;
ie4 = (ie && !dom)?1:0;
mac = (navigator.appVersion.indexOf("Mac") != -1)?1:0;
ie4m = (ie4 && mac)?1:0;
ns6 = (navigator.vendor == ("Netscape6") || navigator.product == ("Gecko"))?1:0;

function findlayer(name) {
    if(dom) return document.getElementById(name);
    else if(ie4) return document.all[name];
    else if(ns4) return document.layers[name];
}

function hide(layer,f) {
	if(!ie) return;
	menu = findlayer('menu'+layer);
	if (menu != null) menu.style.display = "none";
	return;
}

function show(layer) {
	if(!ie) return;
	menu = findlayer('menu'+layer);
	for(i=1;i<=8;i++) {
		menu = findlayer('menu'+layer);
		if (menu != null) menu.style.display = "none";
	}
	if (menu != null) 
	{
		menu.style.display = "block";
		menu.style.visibility = "visible";
	}
	return;
}