diff --git a/web/template/syzoj/problemset.php b/web/template/syzoj/problemset.php
index 2aca384..b841ace 100644
--- a/web/template/syzoj/problemset.php
+++ b/web/template/syzoj/problemset.php
@@ -85,6 +85,7 @@
       $section = 8;
       $start = $page > $section ? $page - $section : 1;
       $end = $page + $section > $view_total_page ? $view_total_page : $page + $section;
+      $query_user_id = $_GET['query_user_id'];
       function get_query_user_id($query_user_id)
       {
         if (!isset($query_user_id))
@@ -102,12 +103,12 @@
         <div class="ui pagination menu" style="box-shadow: none; ">
           <a class="<?php if ($page == 1)
             echo "disabled "; ?>icon item" href="<?php if ($page <> 1)
-                echo get_href(1, $postfix, $_GET['query_user_id']); ?>" id="page_first">
+                echo get_href(1, $postfix, $query_user_id); ?>" id="page_first">
             <i class="angle double left icon"></i>
           </a>
           <a class="<?php if ($page == 1)
             echo "disabled "; ?>icon item" href="<?php if ($page <> 1)
-                echo get_href($page - 1, $postfix, $_GET['query_user_id']); ?>" id="page_prev">
+                echo get_href($page - 1, $postfix, $query_user_id); ?>" id="page_prev">
             <i class="angle left icon"></i>
           </a>
           <?php
@@ -117,12 +118,12 @@
           ?>
           <a class="<?php if ($page == $view_total_page)
             echo "disabled "; ?> icon item" href="<?php if ($page <> $view_total_page)
-                 echo get_href($page + 1, $postfix, $_GET['query_user_id']); ?>" id="page_next">
+                 echo get_href($page + 1, $postfix, $query_user_id); ?>" id="page_next">
             <i class="angle right icon"></i>
           </a>
           <a class="<?php if ($page == $view_total_page)
             echo "disabled "; ?> icon item" href="<?php if ($page <> $view_total_page)
-                 echo get_href($view_total_page, $postfix, $_GET['query_user_id']); ?>" id="page_last">
+                 echo get_href($view_total_page, $postfix, $query_user_id); ?>" id="page_last">
             <i class="angle double right icon"></i>
           </a>
         </div>