var lastMenu = null;
function showMenu(object){
if ((lastMenu!=object)&&(lastMenu!=null)){
	document.getElementById(lastMenu).style.display="none";
	document.getElementById(object).style.display="block";
	lastMenu = object;
}else if(lastMenu==object){
	if(document.getElementById(lastMenu).style.display=="none"){
		document.getElementById(lastMenu).style.display="block";
	}else{
		document.getElementById(lastMenu).style.display="none";
	}
	lastMenu = object;
}else{
	document.getElementById(object).style.display="block";
	lastMenu = object;
}
}