.htaccess using public folder and SEO friendly URL .htaccess is not my strong suit. Is there any there can optimize this code?

RewriteEngine on
RewriteCond %{REQUEST_URI} !^/(public)
RewriteRule (.*) /public/$1

Options +FollowSymLinks -MultiViews
# Turn mod_rewrite on
RewriteEngine On
RewriteBase /

RewriteCond %{REQUEST_FILENAME}.php -f
RewriteCond %{REQUEST_URI} !/$
RewriteRule (.*) $1\.php [L]


ErrorDocument 500 "Sorry, our script crashed. Oh dear"
ErrorDocument 500 /cgi-bin/crash-recover
ErrorDocument 500 http://error.example.com/server_error.html
ErrorDocument 404 /errors/not_found.html
ErrorDocument 401 /subscription/how_to_subscribe.html


don't know if it necessary but here are an example of the folder system


app
public


index.php
contact.php
forum


last_news.php
users


user.php

ask.php


.htaccess
Redundant RewriteEngine declarations
Unused match group in (public)
Escaping (using \) is not needed in the new URLs
A personal touch, but I prefer to keep the core directives at the top, and put module specific directives inside &lt;IfModule&gt; body, so that I won't receive errors if the modules are disabled.
Multiple declarations for ErrorDocument 500




Options +FollowSymLinks -MultiViews

ErrorDocument 401 /subscription/how_to_subscribe.html# Turn mod_rewrite on
ErrorDocument 404 /errors/not_found.html
ErrorDocument 500 http://error.example.com/server_error.html

&lt;IfModule mod_rewrite.c&gt;
    RewriteEngine on
    RewriteBase /

    RewriteCond %{REQUEST_URI} !^/(public)
    RewriteRule ^ /%1%{REQUEST_URI}

    RewriteCond %{REQUEST_FILENAME}.php -f
    RewriteCond %{REQUEST_URI} !/$
    RewriteRule ^(.*)$ $1.php [L]
&lt;/IfModule&gt;