Redirect with Parameters

[mathceleb]

I want to direct any url that has mysite.com/abc/anything
to mysite.com/anything/?abc=yes

where anything can be any text

I've started this below, any thoughts?

rewritecond %{http_host} ^domain.com/abc/$1
rewriterule %{http_host} ^domain.com/$1?abc=yes

[handlegeek]

RewriteEngine On
RewriteCond %{HTTP_HOST} ^mysite\.com$ [NC]
RewriteRule ^abc/(.*)$ http://mysite.com/$1?abc=yes [R=301]