#!/usr/bin/perl
use strict;
use warnings;

my @frau = qw /bl ge gr br sw rt/;
my @mann = qw /ge bl bl br sw rt/;

my %people;
my @paare;

$people{$_}->{f}++ for(@frau);
$people{$_}->{m}++ for(@mann);

while(my($k,$v)=each(%people))
{ push(@paare,$k) if($v->{m} && $v->{f}); }

print "Paare:".join(',',@paare)."\n";