Given the number of replies you have already received, I am suprised no one has pointed you to the FAQs yet. This particular topic is discussed quite nicely in the Perl FAQ

Variations of the question covered in the FAQ can be found in the our very own Categorized Questions and Answers. See QandASection: arrays

In reply to Re: Adding Unique Elements to Array by data64
in thread Adding Unique Elements to Array by thekestrel

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