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Hash of lists in Perl

Archive - Originally posted on "The Horse's Mouth" - 2004-09-09 18:02:29 - Graham Ellis

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!