Thanks for that!
Your explanation is clear and  push @{ $structure->[$i] }, $ex[$i]; In my case, I found this solution, because $structure is not declared. 
push @structure , [];
for (my $i=0;$i<= $#ex; $i++) {
 push @{ @structure->[$j]}, $ex[$i]; 
}

[download]
now I am looping the structure like that 
foreach my $lev1 (@structure) {
  my $cnt = scalar(@{$lev1};
  foreach my $lev2 (@{$lev1}) {
    my %hash = %{$lev2};
    foreach my $key ( keys %hash )
    {         
       # if ($key eq $xx) etc.
    }
   }
}

[download]
Is there a way more straigthforward to fetch the key and the value? maybe wih the map function

In reply to Re^8: Best complex structure? by mat21
in thread Best complex structure? by Anonymous Monk

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