为什么会报错：Parse error:syntax error,unexpected end of file in E:\wamp\www\header.php

<!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=gb2312" />
<title>银子留言板 Version 1.0</title>
</head>
<link href="css.css" rel="stylesheet" type="text/css" />
<body>
<div id="head">
    <div id="head_l">
        <ul>
            <li><a href="index.php">偶要看留言</a></li>
            <li><a href="post.php">偶要发表</a></li>
            <?php
            session_start();
            if($_SESSION["key"]==1){//如果获取的SESSION为1则显示管理项
            ?>
            <li><a href="adminexit.php">退出管理</a></li>
            <?
            }
            else
            {
            ?>
            <li><a href="admin.php">偶要管理</a></li>
            <?}?>
        </ul>
    </div>
    <div id="head_r">银子留言板 Version 1.0</div>
</div>
<?php
$counterFile="conter.xml";
function displayCounter($counterFile){
$fp  =  fopen($counterFile,"rw");
$num =  fgets($fp,5);
$num += 1;
print "<div id=\"footer\">银子留言板 Version 1.0&nbsp;&nbsp;&nbsp;您是第&nbsp;"."$num"."&nbsp;位无聊的银</div>";
exec("rm -rf $counterFile");
exec("echo $num > $counterFile");
}
if(!file_exists($counterFile)){
exec("echo 0 > $counterFile");
}
displayCounter($counterFile);
?></body>
</html>