I have the following coding with the values in drop down list and I would like to delete the duplicated value from the list but I don't know how to do??

```
<select id="dept" name="dept" class="dept" width="100" style="width: 100px">
<?php
while ($line = odbc_fetch_array($result)){
$fullNames=substr($line['fullName'],strpos($line['fullName'],'-')+1);
if ($fullNames==$_POST['dept']){
    $selected="selected=\"selected\"";
}
else {
        $selected="";
}
echo "<option value=\"".$fullNames."\" $selected>".$fullNames."</option>";
}
?>
</select>

```

Existing result in $\_POST['dept']

AC
HR
AC
Admin
MIS
MIS

Expecting result in $\_POST['dept']

AC
Admin
HR
MIS