Re: Why unhashing is not possible?

Barry Margolin wrote:


Surely if the hash is unique, we know the process that got us the hash
we have only to reverse the process... we can't... so... but why not?

How could the hash possibly be guaranteed to be unique?


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

What the hash code designers try to do is make it very hard to find another input that will hash to a given code. Even harder is finding another input that's MEANINGFUL.


This is only true for cryptographic hashes.
.

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