-p0 sub g{my($b,$r)=@_;$s{$b}++||map{$p='.'x8x/[A-Z]/;$s||=$r x$b=~/$c /||g($n=$b,"$r$c ".($n=~s/$_(($p$c)+$p)(?!$_)($c| )/$3$1$_/s-2*/ /).$/)for$",$c=$_}$b=~/\w/g;$s}$_=g$_