gistfile1.txt

$last_reply_time = 0;
if (isset($comments[(count($comments) - 1)])) {
	$last_reply_time = strtotime($comments[(count($comments) - 1)]->comment_date_gmt);
}
else if (count($social_items)) {
	$latest_item = null;
	foreach ($social_items as $service => $items) {
		foreach ($items as $comment) {
			if ($latest_item === null) {
				$latest_item = strtotime($comment->comment_date_gmt);
			}
			else {
				$time = strtotime($comment->comment_date_gmt);
				if ($time > $latest_item) {
					$latest_item = $time;
				}
			}
		}
	}

	if ($latest_item !== null) {
		$last_reply_time = $latest_item;
	}
}