window.onload = function(){
	var menu_lat = document.getElementById("menu_1");
	/*var a_ul = menu_lat.getElementsByTagName("ul");
		for(i=0; i < a_ul.length; i++){
			a_ul[i].style.display = "none"
			}
		*/
	
	
	var a_li = menu_lat.getElementsByTagName("li");
	// alert(a_li.length)
		for(i=0; i<a_li.length; i++){
			if(a_li[i].className == "primi"){
				a_li[i].onmouseover = show_hide;
				a_li[i].onmouseout = show_hide;
			}
		}
	}
	
	
// funzione che mostra e nasconde i sottomenu	
function show_hide(){
	if(this.getElementsByTagName("ul")[0].style.display == "block"){
		this.getElementsByTagName("ul")[0].style.display = "none";
		}
	else {
		this.getElementsByTagName("ul")[0].style.display = "block";
		}
	}