#!/usr/bin/perl

use warnings;
use strict;

package Person {

    sub new { 
        my $classname = shift;
        my $args = {@_}; 
        my $self = { name => $args->{name},
                     betreff => $args->{betreff},
                     konsumref => $args->{konsumref} };
        return bless($self, $classname); 
    }           

    sub showKonsum {
        my $self = shift;
        my @konsum = @{$self->{konsumref}};
        my $i;
        print "\n";
        print $self->{betreff} . ":\n";
        print "Konsum ist:\n";
        for $i (@konsum) {
            print "$i\n";
        }
        print "\n";
        print "Summe Konsum: " . $self->getSum() . "\n";
        print "Durschnittlich: " . $self->getAverageKonsum() . "\n\n";
    }

    sub getSum  {
        my $self = shift;
        my @konsum = @{$self->{konsumref}};
        my $sum = 0;
        my $i;
        for $i (@konsum) {
            $sum += $i;
        }
        return $sum;
    }

    sub getAverageKonsum  {
        my $self = shift;
        my @konsum = @{$self->{konsumref}};
        my $konsumlen = @konsum;
        my $sum = $self->getSum();
        return $sum / $konsumlen;
    }

}

my $A = Person->new(name => "Alfred",
                    betreff => "Monatliche Sushibarbesuche im halben Jahr", 
                    konsumref => [4, 2, 5, 7, 5, 3]);
$A->showKonsum();