use strict;
use warnings;

my $fc = <<FC;
#4 
r0 !
r1 !
r2 !
#5
r3 !
r4 !
r5 !
FC

print "$1\n$2\n" while $fc =~ /^(#\d+).*?^.*?^(.*?)$/gms;

##</code><code>##

#4
r0 !
#5
r3 !