A Perl regex that matches composite numbers (and doesn't match prime numbers)Take a look at this Perl regular expression: perl -lne '(1x$_) =~ /^(11+?)\1+$/ && print "$_ is composite"' This regular expression matches only the composite numbers (and doesn't match prime numbers). Can you figure out how it works? I'll give the explanation below but try to figure it out yourself. Here is what happens when you run it: $ perl -lne '(1x$_) =~ /^(11+?)\1+$/ && print "$_ is composi
