http://qs321.pair.com?node_id=361092

#!/usr/bin/perl -w local $\ = "\n"; while (<>) { chomp; $_ && print $_>0 ? "positive $_" : "negative ".($_*-1); }
#Remove those pesky ^M (note the ^V will not be visible) perl -pi -e 's/^V^M//g' <filename>
http://www.perlmonks.org/index.pl?node_id=138068&lastnode_id=137863