Here's a short program that reads data into a hash of lists, sorts the keys and displays output data - a simple Perl program showing powerful capabilities of the language.

while () {

        my ($name,@temporary) = split;

        $want{$name} = \@temporary;

        } 



foreach $person (sort keys %want) {

        print $person," ",$want{$person}[0]," ",$#{$want{$person}}+1,"\n";

        }



__DATA__

antonia Perl XML PHP Tcl/Tk MySQL

ethel MySQL Perl Tcl/Tk ASP

iris  Perl MySQL Java Tcl/Tk

olivia  MySQL Python ASP PHP

uva MySQL Perl Java PHP

adam Tcl/Tk Perl Python MySQL

ed Ruby Perl Java PHP 

ivan Ruby Java Perl Tcl/Tk MySQL

orpheus MySQL Ruby Tcl/Tk XML

ulsyees Java PHP Perl

Results:

adam Tcl/Tk 4

antonia Perl 5

ed Ruby 4

ethel MySQL 4

iris Perl 4

ivan Ruby 5

olivia MySQL 4

orpheus MySQL 4

ulsyees Java 3

uva MySQL 4

A little demo I wrote today while talking about more complex data structures.

Things always turn out so easy in Perl!
(written 2004-09-09, updated 2006-06-05)

 P217 - Perl - More than Simple Lists and Hashes!
  [3577] How to do multidimensional arrays (or rather lists and hashes) in Perl - (2012-01-14)
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  [3118] Arrays of arrays - or 2D arrays. How to program tables. - (2011-01-02)
  [3105] Adventure with references to lists and lists of references - (2010-12-26)
  [3072] Finding elements common to many lists / arrays - (2010-11-26)
  [3007] Setting up a matrix of data (2D array) for processing in your program - (2010-10-21)
  [2996] Copying - duplicating data, or just adding a name? Perl and Python compared - (2010-10-12)
  [2877] Further more advanced Perl examples - (2010-07-19)
  [2840] Just pass a pointer - do not duplicate the data - (2010-06-30)
  [2241] Perl references - $$var and \$var notations - (2009-06-15)
  [1514] Autovivification - the magic appearance of variables in Perl - (2008-01-21)
  [293] Course follow-ups - (2005-04-27)

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