#!/usr/bin/perl

use strict;
use warnings;

use Data::Dumper;

my @folks = qw(Hans Maria Jochen Hans Maria Johann Hans Rainer);
my %seen;

for (0 .. $#folks) {
    $seen{$folks[$_]}->{cnt}++;
    push @{$seen{$folks[$_]}->{position}}, $_;
}

print Dumper \%seen;

my @unique = map { { $_ => $seen{$_} } } grep { $seen{$_}->{cnt} == 1 } keys %seen;
my @often  = map { { $_ => $seen{$_} } } grep { $seen{$_}->{cnt} > 1 } keys %seen;

print Dumper \@unique, \@often;