How to insert Adsense Code in the Middle of a Post?

So sorry for the delayed response. I didn't know there was a response to my question.

The answer is yes, I'm using Wordpress.

Actually, I've found a script on the web to do it. But, eventually I didn't use it because due to the nature of my site, inserting an ad automatically in the middle of a page will ruin some of my pages.

I'm reproducing the PHP script here for those who may need a similar script. The script is not from me, so I cannot take credit for it, neither can I provide any support.

//Find an appropriate position near the middle of the content to insert an ad
function insert_ad_in_middle_post($content) {
$output = '';
$positions = array();
$endpos = -1;
$trigger = "<p";
if(strpos($content, "<p") === false)
$trigger = "<br";

while(strpos($content, $trigger, $endpos+1) !== false){
$endpos = strpos($content, $trigger, $endpos+1);
$positions[] = $endpos;
}
$middle = sizeof($positions);
while(sizeof($positions) > $middle)
array_pop($positions);
$triggerpoint = $positions[floor(sizeof($positions)/2)];

if ($middle > 2) {
$ad_style = 'clear:both;margin:15px 0 15px 0;padding:0;border:1px solid #ccc;';
if(is_single()) {
$content = substr_replace($content, '<div style="'.$ad_style.'"><!-- Insert Ad Code --></div>'.$trigger, $triggerpoint, 2);
}
}

$content = $output.$content."<div style='clear:both'></div>";
return $content;
}
add_filter('the_content', 'insert_ad_in_middle_post');

Just switch to HTML view and insert the script into the post.