Thoughts in combinatorial logic

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From	Sylvia Else <sylvia@email.invalid>
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Subject	Thoughts in combinatorial logic
Date	Mon, 1 Apr 2019 16:11:04 +1100
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As part of a personal project I'm working on, I needed a combinatorial 
logic way of obtaining the lowest set bit from a collection of bits. 
That is, taking n inputs in some order, and by using only and/or/not 
gates, produce n outputs of which only one is set, being that which 
corresponds to the lowest order set input bit

It's not especially difficult.

But suppose the requirement is not the lowest set bit, just any of the 
set bits.

Clearly, the solution to the first requirement is also a solution to the 
second requirement, but is the second requirement amenable to a simpler 
(as in, using fewer gates) solution.

My intuition is that it's not, but I haven't been able to prove it.

Sylvia.

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Thoughts in combinatorial logic Sylvia Else <sylvia@email.invalid> - 2019-04-01 16:11 +1100
  Re: Thoughts in combinatorial logic Marko Rauhamaa <marko@pacujo.net> - 2019-04-01 16:28 +0300
  Re: Thoughts in combinatorial logic not@telling.you.invalid (Computer Nerd Kev) - 2019-04-02 22:08 +0000
    Re: Thoughts in combinatorial logic not@telling.you.invalid (Computer Nerd Kev) - 2019-04-03 07:47 +0000
  Re: Thoughts in combinatorial logic Bruce Horrocks <07.013@scorecrow.com> - 2019-04-02 23:11 +0100
    Re: Thoughts in combinatorial logic Sylvia Else <sylvia@email.invalid> - 2019-04-03 09:34 +1100
  Re: Thoughts in combinatorial logic Bruce Horrocks <07.013@scorecrow.com> - 2019-04-05 10:48 +0100
    Re: Thoughts in combinatorial logic Sylvia Else <sylvia@email.invalid> - 2019-04-11 20:33 +1000

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