Re: Why unhashing is not possible?

In article <uvgcj.20007$wy2.19474@edtnps90>,
Unruh <unruh-spam@xxxxxxxxxxxxxx> wrote:
"Sebastian G." <seppi@xxxxxxxxx> writes:

Barry Margolin wrote:

How could the hash possibly be guaranteed to be unique?

For a limited set of inputs, this is very easy.

Yes. then it is not a hash. It may be an encryption, or a translation.

http://en.wikipedia.org/wiki/Perfect_hash_function

http://burtleburtle.net/bob/hash/perfect.html
"Minimal perfect hashing"


I've never seen Perfect Hashing referred to as an encryption or
translation, only ever as a "hash function".
.

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