Hello Monks, I have a hash table from which I would like to print 20 keys with the highest values. I currently have this code: 

my %top_words =  reverse %words  
#reverse to sort by value as opposed to key

%top_words = sort {$top_words{$b} <=> $top_words{$a}} %top_words; # so
+rt z-a to get the highest ones at the top

my $counter=0;
foreach my $value (%top_words)
{ if ($counter > 20) {last;} #exit loop
print "$top_words{$value}\n";
$counter++;
}
#print 20 words with highest value

[download]

This returns numbers, and the following error message:

 Use of uninitialized value within %top_words in concatenation (.) or string at ./test.pl line 114. I can't see the error, and line 114 is the print command. Thank you.

In reply to Printing keys from a hash by value? by jms53

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