一个比较菜的问题，想了很久没法解决！特此求助！


<style>
.dong{background-color:red}
.jing{background-color:blue}
</style>
<div id="box"> 
     <div class="dong" id="my_div1_10" onmousemove=tab(this)>栏目1 </div>  //栏目标题 
     <div id="my_div2_10">11111 </div>    //栏目包含的内容 
     <div class="jing" id="my_div1_11" onmousemove=tab(this)>栏目2 </div> 
     <div id="my_div2_17" style="DISPLAY: none">2222 </div> 
     <div class="jing" id="my_div1_12" onmousemove=tab(this)>栏目3 </div> 
     <div id="my_div2_12" style="DISPLAY: none">3333 </div> 
       //注：中间没有13到15     
     <div class="jing" id="my_div1_16" onmousemove=tab(this)>栏目4 </div> 
     <div id="my_div2_16" style="DISPLAY: none">4444 </div> 
</div>
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for(var i=0;i<objs.length;i++)
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if(/^my_div1_(\d+)$/.test(objs[i].id))
{
var indexDiv1=RegExp.$1
var indexDiv2=objs[i+1].id.replace(/my_div2_/,"")
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objs[i].className="dong"
objs[i+1].style.display="block"
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objs[i].className="jing"
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}
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showDiv()
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