One way is to use sort and length: 
use strict;
use warnings;

my @args = sort { length($b) <=> length($a) } @ARGV;
print "longest is $args[0], length = ", length($args[0]), "\n";

__END__

longest is ert, length = 3

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See also: How do I compose an effective node title?

In reply to Re: Simple Perl, to get me started. by toolic
in thread Simple Perl, to get me started. by Lust69

Title:
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