Conditional statements for advertising

[Opserty]

<if condition="in_array($forumid, array(1,2,3,4))">
    <!-- Category 1 Ad Code -->
<else />
    <if condition="in_array($forumid, array(5,6,7,8))">
        <!-- Category 2 Ad Code -->
    <else />
        <!-- We're not in category 1 or 2 -->
    </if>
</if>