in reply to Hash Printing reveals Hash Memory Location
In addition to tobyink's post above, I would suggest using strict and warnings in your code. This will ensure that Perl will warn you about any dubious constructs in your code. For instance, the line my %words = {}; would have resulted in the message Odd number of elements in hash assignment. These messages can be quite useful and often point you in the right direction if your code isn't behaving as expected. The perldiag manpage can be used to look up the meanings of the messages and the diagnostics pragma can be used to print out the more verbose messages from perldiag.
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