By default build perl shares keys accross all hashes. That way when you have a zillion hashes with the same keys the keys arent duplicated in memory. To store all those keys it uses another hash that really holds the keys. So when you insert a new key into your hash its hash number is calculated and then that number is used to store into both hashes. Which means that hash has to grow as well.

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demerphq

In reply to Re^6: better union of sets algorithm? by demerphq
in thread better union of sets algorithm? by perrin

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