function showHide(id,cl) {
var myclass = new RegExp('\\b'+cl+'\\b');
var elem = document.getElementsByTagName('body')[0].getElementsByTagName('*');
for (var i = 0; i < elem.length; i++) {
var classes = elem[i].className;
if (myclass.test(classes)) elem[i].style.display = 'none' ;
}
if (id) document.getElementById(id).style.display = 'block';
}
window.onload = function() {showHide('a1','one');}