随机三位字母，注册域名时用的
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>
<body>
<script type="text/javascript">
for(var i=0;i<26;i++)
for(var j=0;j<26;j++)
for(var k=0;k<26;k++)
{
document.write(String.fromCharCode(65+i)+String.fromCharCode(65+j)+String.fromCharCode(65+k)+"<br>");
}
</script>
</body>
</html>
