function showSub(el) {
    if (el.getElementsByTagName('ul')[0]!=null) {
        el.getElementsByTagName('ul')[0].style.display = 'block';
        el.getElementsByTagName('a')[0].className = 'selected';
    }
}
function hideSub(el) {
    if (el.getElementsByTagName('ul')[0] != null) {
        el.getElementsByTagName('ul')[0].style.display = 'none';
        el.getElementsByTagName('a')[0].className = '';
    }
}