#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;

my @daten = (
 ['hosen','jeans','modern'],
 ['hosen','shorts'],
 ['roecke','mini']
);

my $hash = {};

foreach my $data (@daten) {
   if(ref $data eq 'ARRAY') {
      my $max = scalar(@{$data});
      my $start = $hash;
      for my $i (1 .. $max) {
          my $key = $data->[$i-1];
          my $val = $i == $max ? 1 : {};      
          $start = prepareOrSet($start, $key, $val);
      }
   }
}

sub prepareOrSet {
   my ($href, $key, $val) = @_;
   $href->{$key} = $val unless defined $href->{$key};
   return $href->{$key};
}

print Dumper $hash;