Alternate markup for every 6 post - in wordpress

I want to put in and ad code after every 6 post on my blog. I cant really figure out how to break out of the foreach and insert 开发者_高级运维the ad code.

This link will help you. Third title says: Insert Ads After The First Post

Change the code for 6 where it says 2:

<?php if (have_posts()) : ?> // Here we check if there are posts
<?php $count = 0; ?>
<?php while (have_posts()) : the_post(); ?>
<?php $count++; ?> // While we have posts, add 1 to count
  <?php if ($count == 6) : ?> // If this is post 6
          //Paste your ad code here
          <h2><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></h2> // post title
          <?php the_excerpt(); ?> // You may use the_content too
   <?php else : ?> // If this is not post 6
          <h2><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></h2>
          <?php the_excerpt(); ?>
  <?php endif; ?>
<?php endwhile; ?>
<?php endif; ?>

UPDATE: As Gordon noticed, you asked for code every 6 posts (sorry I missed that on my first read). So the code should be:

<?php if ($count % 6 == 0) : ?>

As what @Gordon commented, here's how I'd re-factor that code;

<?php if (have_posts()) : $count = 1; while (have_posts()): ?>

    <?php if ($count == 6) : ?>

          // Paste your ad code here

    <?php $count = 0; endif; ?>    

    <h2><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></h2>
    <?php the_excerpt(); ?>

<?php $count++; endwhile; endif; ?>