Htaccess rewrite rule causing Forbidden access - php

Question

I'm trying to hide subfolders from url like this:
localhost/imo/public_html/public/ajuda.php to localhost/imo/ajuda
Its working well if the file exist, if not i get a forbidden access like this:
You don't have permission to access
/imo/public_html/public/public_html/public/public_html...public/contacto.php.php.php.php.php.php.php.php.php.php
on this server.
this is my htaccess file:
<IfModule mod_rewrite.c>
Options +SymLinksIfOwnerMatch
RewriteEngine On
RewriteRule ^$ public_html/public/
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
#RewriteCond %{REQUEST_FILENAME}.php -f
RewriteRule ^(.*)$ public_html/public/$1
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
#RewriteCond %{REQUEST_FILENAME}.php -f
RewriteRule ^(.*)$ $1.php [L,QSA,NC]
</IfModule>
I already search on stackoverflow and it seems that the rules is causing a loop but the solutions provided didn't work on my case so far. Any help at all would be very aprecciated.
Thank you.
UPDATE
Thanks to #Matthijs Otterloo this is the working htaccess script:
<IfModule mod_rewrite.c>
Options +SymLinksIfOwnerMatch
RewriteEngine On
RewriteRule ^$ public_html/public/
RewriteCond %{REQUEST_URI} !^/public_html/public
RewriteRule ^/?([^/]+)$ /public_html/public/$1 [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}.php -f
RewriteRule ^(.*)$ $1.php [L,QSA,NC]
</IfModule>

Answer 1

Try something like this in your .htaccess file:
RewriteEngine On
RewriteCond %{REQUEST_URI} !^/public_html/public
RewriteRule ^/?([^/]+)$ /public_html/public/$1 [L]
Best way would be to set-up propper virtual hosts but this should fix it.