I am trying to write a program that searches through a directory, and finds files with names that look like this: 
xx_000000

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where the 'xx' is a two-letter city abbreviation and the number is just a six digit ID number. What I then want to do is open the file, and store all the data in a array-of-a-hash-of-a-hash - I think. Honestly, I have a very difficult time with these types of structures. Here is what I am doing: 
my %city_data = ();
my ($city, $id) = split(/_/,$filename);
open(THIS,"$filename") or die;
my @tmp = <THIS>; close(THIS);

push @{ $city_data{$city}{$id} }, @tmp;

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Now, it seems like this should work correctly, but I can't tell if it does. First of all, is my approach correct? Secondly, if so, how would I print out everything that is in the @{$city_data{$city}{$id}} array? I know that this may be a simple question for most, and I have read everything I could find on PM and elsewhere about this subject, but I am still lost. Could someone please try to explain this to me, in detail if you wouldn't mind, so that hopefully the next time I have a problem like this I am not as lost as I am now? Thanks so much to all the gracious helpers out there (and to all who aren't so gracious, thanks anyway :-).

R.Joseph

In reply to Confused about complex data structures. by r.joseph

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