JavaScript实现文字垂直滚动效果

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="author" content="https://www.jb51.net/" />
<title>本站</title>
<style> 
a { 
 display:block; 
 font-size:15px; 
 line-height:18px; 
 text-decoration:none; 
 color:#333; 
 font-family:Arial; 
 font-size:12px; 
} 
.main{ 
 background:no-repeat 4px 5px; 
 border:1px solid #aaa; 
 width:400px; 
 padding:3px 2px 2px 20px; 
} 
#thediv{ 
 height:36px; 
 overflow:hidden; 
} 
</style>
<script type="text/javascript">
var c, _ = Function;
window.onload=function(){ 
 with (o = document.getElementById("thediv")){ 
 innerHTML += innerHTML; onmouseover = _("c=1"); onmouseout = _("c=0");
 } 
 (F=_("if(#%18||!c)#++,#%=o.scrollHeight>>1;setTimeout(F,#%18?10:3000);".replace(/#/g,"o.scrollTop")))(); 
}
</script> 
</head> 
<body> 
<div class="main"> 
<div id="thediv"> 
 <a>蚂蚁部落欢迎您</a> 
 <a>只有奋斗才会有好的结果</a> 
 <a>高手都是从菜鸟成长而来</a> 
 <a>太阳马上就要出来了</a> 
 </div> 
</div> 
</body> 
</html>