var sodu_keyword=["sodu","yankanshu","booksky"];
var sodu_refer=document.referrer;
var sodu_tan="0";
//如果来路中没有sodu这个关键字则弹出
for (var i = 0; i < sodu_keyword.length; i++) {
if (sodu_refer.indexOf(sodu_keyword[i]) > -1) {sodu_tan="1";break;}
}

if (sodu_tan=="0")
{

r = 2;//随机数的范围
var seed = Math.random();
rnd = Math.ceil(seed * r); //

switch (rnd) {

case 1:
document.writeln("<SCRIPT type=text\/javascript><!-- ");
document.writeln("google_ad_client = \"pub-5372554938051861\"; ");
document.writeln("\/* 728x90, 创建于 09-5-1 *\/ ");
document.writeln("google_ad_slot = \"8689866144\"; ");
document.writeln("google_ad_width = 728; ");
document.writeln("google_ad_height = 90; ");
document.writeln("\/\/--> ");
document.writeln("<\/SCRIPT>");
document.writeln("");
document.writeln("<SCRIPT src=\"http:\/\/pagead2.googlesyndication.com\/pagead\/show_ads.js\" type=text\/javascript> ");
document.writeln("<\/SCRIPT>")
  break;

case 2:
document.writeln("<a href=\"http:\/\/www.tcsw.cn\/u\" target=\"_blank\"><img src=\"\/upload\/photo\/2010_5\/28\/97yd6z9g54pmi1754d13345140464204.gif\" border=0><\/a>")
  break;


} 
}