:
$!N
s/\.\*\?/a&b876543210&/
s/\*a/&+/
s/\*.\{15\}a/&+/
s/\*.\{16\}a/&+/
s/\*.\{17\}a/&+/
s/b.\{25\}\*/+&/
s/b.\{26\}\*/+&/
s/b.\{27\}\*/+&/
s/a\(.\)\{11\}\w*./\1/
t
Note that non-ascii characters in the above source code will be escaped (such as \x9f).