Hashes are known to be innefiicient uses of memory. Thats the tradeoff you get for speed.

One thing I did recently discover is that a nearly full hash will tend to have its elements in some kind of well defined order.
For example if you do letter frequency analysis of a large document because you think this might be fun for cryptography you end up with a hash %frequencies which contains most of the ASCII character set from 32 to 127 and they are also in nearly alphabetical order that is keys %frequencies produces a list ... 'A', 'B', 'C', 'D' ...

Dingus

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