apache - Excluding filename using RewriteRule -

i want pipe uris index.php unless specific file exists in root. i'm little stumped when comes excluding index.php of course won't match last catch rule

options +followsymlinks -indexes rewriteengine on  rewritecond %{request_filename} !-d rewritecond %{request_filename} !-f rewritecond %{request_filename} != "index/.php" // i'm not sure on syntax here rewriterule ^(.*)$ $1.php [l]  rewriterule ^([^/]*)(.*)$ index.php?category=$1&post=$2 [l,qsa] 

solved adding additional conditions last rule

rewritecond %{request_filename}\.php -f rewriterule ^([^\.]+)$ $1.php [l]  rewritecond %{request_filename} !-d rewritecond %{request_filename} !-f rewriterule ^([^/]*)(.*)$ index.php?category=$1&post=$2 [l,qsa]