Problems with hash of hashes in perl -

i have problem accessing variables in hash of hashes don't know have done wrong. while debugging value of hash %list1 gives undef, can't values out .

use strict ; use warnings ; $text = "the, big, fat, little, bastards"; $author = "alex , shuman ,directory"; %hashes  = {1,2,3,40}; %count  = (); @lst = split(",",$text); $i = 0 ; @authors  =  split(",", $author); foreach  $singleauthor(@authors) {     foreach $dig (@lst)     {       $count{$singleauthor}{$dig}++;     } }  counter(\%count);  sub counter {     $ref  =  shift;     @singleauthors = keys %$ref;     %list1;     foreach  $singleauthor1(@singleauthors)   {       %list1 =  $ref->{$singleauthor1};     foreach $dig1 (keys %list1)     {       print  $ref->{$singleauthor1}->{$dig1};     } }   } 

in 2 places attempting assign hash reference hash, results in warning: reference found even-sized list expected.

here 2 edits need:

# changed {} (). # however, never use %hashes, i'm not sure why it's here @ all. %hashes  = (1,2,3,40);  # added %{} around right-hand side. %list1 =  %{$ref->{$singleauthor1}}; 

see perlreftut useful , brief discussion of complex data structures.

for it's worth, counter() method simplified without loss of readability dropping intermediate variables.

sub counter {     $tallies = shift;     foreach $author (keys %$tallies) {            foreach $dig (keys %{$tallies->{$author}}) {             print $tallies->{$author}{$dig}, "\n";         }     } } 

or, ysth points out, if don't need keys:

    foreach $author_digs (values %$tallies) {            print $dig, "\n" values %$author_digs;     }