Why my htaccess rules do not work perfectly?
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I want to make 2 types of URL with these styles using htaccess and mod_rewrite.  

    http://www.site.com/product
    http://www.site.com/product/1/something
For this, I've added these lines to the htaccess file:

    Options +FollowSymLinks
    RewriteEngine On

    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d

    RewriteRule ^([^/]*)/([^/]*)/([^/]*)$ /index.php?p=$1&id=$2&des=$3 [N]
    RewriteRule ^([^/]*)$ /index.php?p=$1 [F]
But whenever I run my application and hint **http://localhost/project/**, web server redirect me to **http://localhost/**.
  
Now I have 2 questions:  

 1. Why do I redirect to localhost and why the codes above do not work ?
 2. How can I add a trailing slash to the end of clean URLs?