function show(n){  
var o = document.getElementById('tabtn').getElementsByTagName("a");  
var c = document.getElementById('tabContent').getElementsByTagName("ol");  
for(i = 0; l = o.length, i < l; o[i].className = '',c[i].style.display = 'none',i++ );  
o[n].className = 'over';  
c[n].style.display = 'block';  
} 
//今日协会tab
function dshow(n){  
var o = document.getElementById('downtit').getElementsByTagName("a");  
var c = document.getElementById('dcontent').getElementsByTagName("ol");  
for(i = 0; l = o.length, i < l; o[i].className = '',c[i].style.display = 'none',i++ );  
o[n].className = 'over';  
c[n].style.display = 'block';  
} 
//下载tab