I need help converting htaccess into nginx config

I have small 6 lines htaccess and I need some one expert converting that htaccess into nginx config.

This is my config

Options -Multiviews
<IfModule mod_rewrite.c>
RewriteEngine On

RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-s
RewriteRule ^(.*)$ index.php?x=$1 [QSA,NC,L]

RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^(.*)$ index.php [QSA,NC,L]

RewriteCond %{REQUEST_FILENAME} -s
RewriteRule ^(.*)$ index.php [QSA,NC,L]
</IfModule>