23 Jun
2023
23 Jun
'23
6:45 p.m.
Thought Email List: unsolvable puzzle fun Subject: Re: reversing simple hashes From: confident naive puzzler
maybe we could think about the XOR function. i recall it has a basic problem regarding unknownness of the precise inputs.
XOR can totally be reversed. 100%. A B XOR 0 0 0 0 1 1 1 0 1 1 1 0 It's defined by a lookup table, so if you know the XOR output you know an immediate function of one input given the other, and you know the complete set of possible combinations of inputs and outputs. It gets more complex when you have millions of them rather than just one! I wouldn't put something that hard to rewind in the time travel thing. But maybe the xor function could be an example they would use?