# [spam][spam][spam] crazy

Undescribed Horrific Abuse, One Victim & Survivor of Many gmkarl at gmail.com
Fri Jun 23 12:18:21 PDT 2023

```Thought Email
List: unsolvable puzzle fun
To: excited puzzler, shaky naive puzzler 2
From: shaky naive puzzler
Subject: Re: reversing xor with random data was: Re: reversing simple hashes

I hear ya, I hear ya.

Over the years we often look for ongoing puzzles to work on. I'm
thinking of adding some thoughts around this one, which seems to
overlap with the timetravel one slightly in likely designs that would
solve it and also have a little coolness too.

So, how would we turn a 10%/90% distribution into a way to look up the
probability of a given byte?
Each byte is made of 8 bits. Each bit has either a 10% or a 90% chance.
So each bit has a probability.
The product of all these probabilities would be taken, since each one
selects from among the possibilities in which the others are the case.
The sum of all 256 probabilities would be 1.0 .
The probability could be calculated by taking the bitsum and 8-bitsum,
and raising the probabilities to the power of these bitsums.
```