your code or data here

use strict;
print "your perl code here\n";

#!/usr/bin/perl

use strict;
use warnings;

use Data::Dumper;
$Data::Dumper::Useqq = 1;

#!/usr/bin/perl
#use strict;
use warnings;
use Text::CSV;

my %datei = (
shop => 'xt_customers.csv',
wawi => 'xt_customers.txt',
neu => 'all_customers.csv',
);
sub load_cache {
    my $file = shift;
    my %cache;
    my $csv = Text::CSV->new ( { binary => 1 , sep_char => ";" } )
    or die "File not found: ".Text::CSV->error_diag ();
    my $row;
    open my $fh, "<:encoding(iso-8859-1)", $file or die $file." $!";
    while ( $row = $csv->getline ( $fh ) and ref $row eq 'ARRAY') {
        $cache{'ID'}{ $row->[0] } = $cache{'Mail'}{ $row->[6] } = $row;
#$cache{'ID'}{@$row[0]} = $cache{'Mail'}{@$row[6]} = $row;
    }
    return \%cache;
}
# lade beide dateien
my $cache_shop = load_cache( $datei{'shop'} );
my $cache_wawi = load_cache( $datei{'wawi'} );
my $cache_neu = (load_cache $datei{shop} )->{ID};
# kopiere alle zeilen aus wawi in neuen shop deren id oder mail nicht im shop ist
for my $ID ( keys %{ $cache_wawi->{'ID'} }) {
    $cache_neu->{ $ID } = $cache_wawi->{'ID'}->{ $ID }
    if not exists $cache_shop->{'ID'}->{ $ID }
    and not exists $cache_shop->{'Mail'}->{ $cache_wawi->{'ID'}->{$ID}->[6] };
}
# gib die neue shopliste aus
for my $row ( values %$cache_neu ) { print join(';', @$row[0..17]);print"\n" }