Redirect .htaccess only when no subdomain

Hello. I have a .htaccess who redirect all request do the /public/ directory. But i want only redirect when no subdomain… Actual .htaccess :

RewriteEngine On
RewriteBase /
RewriteCond %{THE_REQUEST} /public/([^\s?]*) [NC]
RewriteRule ^ %1 [L,NE,R=302]
RewriteRule ^((?!public/).*)$ public/$1 [L,NC]

Thanks.