function DropdownMenu(num) 
    {
            document.getElementById("mainmenuitem"+num).style.display = "block";
    }
    
    function PullupMenu(num)
    {
            document.getElementById("mainmenuitem"+num).style.display = "none";
    }
    
    function PullupSubMenu()
    {
        document.getElementById("mainmenuitem"+num).style.display = "none";
    }