s%(<p>(?=(?:(?!</p>).)*\n\n)(?:(?!</p>).)*</p>)%-->$1<--%sg


##</code><code>##

    s{ (<p>
         (?=(?:(?!</p>).)*\n\n) # Followed by two newlines not preceded by </p>
         (?:(?!</p>).)*</p>)    # Followed by </p> not preceded by </p>
     }{-->$1<--}sgx;


##</code><code>##

my $not_followed_by_end_p = qr{(?:(?!</p>).)*}s;
while (<>) {
    s{ (<p>
         (?=$not_followed_by_end_p\n\n)
         $not_followed_by_end_p</p>)
     }{-->$1<--}gx;
    print;
}


##</code><code>##

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,