Hi Japhy,
I was practicing your difference script but I got the following error when I ran my script: syntax error at ./shopdiff.pl line 5, near "++ for " Execution of ./shopdiff.pl aborted due to compilation errors. Here is my script: #!/usr/local/bin/perl -w sub difference { my %seen; for (@_) { $seen{$_}++ for @$_ } return grep $seen{$_} == 1, keys %seen; } $listss = 'stopandshop'; $listshaws = 'shaws'; open (SS, $listss); open (SHAWS, $listshaws); @ss = <SS>; @shaws = <SHAWS>; @diff = difference (\@ss, \@shaws); print @diff, "\n"; ------ I created two lists stopandshop and shaws and put inside a few common items besides unique items. thanks for your help! Pinar -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]