function open_sub(sub) {
var strsub = "";
for (var i = 1; i <= 5; i++) {
	strsub = "sub" + i;
	document.getElementById(strsub).style.display = "none";
}
document.getElementById(sub).style.display = "block";
}

function hide_menu() {
var strsub = "";
for (var i = 1; i <= 5; i++) {
	strsub = "sub" + i;
	document.getElementById(strsub).style.display = "none";
}
}

function show_menu(menu) {
document.getElementById(menu).style.display = "block";
}