This should work, and is clear to read. While it is not optimally efficient, efficiency shouldn't be your concern at this stage. If this isn't working, you need to post more information about your actual script. Posting real input, expected output, and actual code (all wrapped in <code> tags) will greatly facilitate the debugging. As discussed in How do I post a question effectively?.
in reply to Re^2: using hashes
in thread iterating hash keys?
#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.