http://qs321.pair.com?node_id=1148841


in reply to Re: Tree Structure Challenge
in thread Tree Structure Challenge

How should I run your solution to get the result for the following?
'Zoo'->diff( 'Zoo'->new(qw( Dog Fox Wolf )), 'Zoo'->new(qw( Fox )));

Not saying that I'm getting

Can't use an undefined value as an ARRAY reference at ./zoo.pl line 40 +.
($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,