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A comment on Long out of math, an AI programmer cracks a pure math problem. Parent comment

Re:Long out of math, an AI programmer cracks a pure math pro... by koolba on Tuesday January 03, 2023 @03:59PM (#34237954)
The 12-ball problem is a fun one and IMO the key revelation is that you do not need to determine whether the ball is lighter or heavier (which isn’t possible anyway). Just which ball is different than the rest. It’s a great exercise in decision trees as you change your strategy based on total information, not just the most recent step.

It’s also fun to scale the problem from 3 balls up to see how the solution evolves.

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Re:Long out of math, an AI programmer cracks a pure math pro... by hgsgm on Tuesday January 03, 2023 @04:39PM (#34238466)
Scale down first! Interesting patterns start from 0 and 1.
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Re:Long out of math, an AI programmer cracks a pure math pro... by thaumasiotes on Tuesday January 03, 2023 @05:17PM (#34238927)
>> you're given 12 metal balls and told that one of them is either heavier or lighter than the rest. You're then given a balance/scale and instructed to figure out which ball is different and whether it is heavier or lighter using the balance a maximum of three times

> The 12-ball problem is a fun one and IMO the key revelation is that you do not need to determine whether the ball is lighter or heavier (which isn’t possible anyway).

Huh?

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Re:Long out of math, an AI programmer cracks a pure math pro... by vgb2k18 on Tuesday January 03, 2023 @05:34PM (#34239109)
If I'm reading this [0] right, the heavier/lighter factor can be determined within 3 weightings... [0] https://suresolv.com/brain-teaser/find-fake-ball-among-12-id...
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Re:Long out of math, an AI programmer cracks a pure math pro... by thaumasiotes on Tuesday January 03, 2023 @05:43PM (#34239213)
Of course it can. There are 24 possible states and you get enough information to uniquely identify one of 27 states. This was already stated in the root comment.

I'm confused how the response to "you must identify whether the odd ball is heavier or lighter" can be "the key to this is realizing you don't need to know whether the odd ball is heavier or lighter, which is good because that's impossible anyway".

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Re:Long out of math, an AI programmer cracks a pure math pro... by vgb2k18 on Tuesday January 03, 2023 @09:09PM (#34241044)
Sorry, yes I saw your confusion. If you read back to your Huh comment you might forgive me for reading it as that you were unsure of the truth yourself. The one word 'huh?', spoke to me as "which one of these is true?". Whereas a person who was sure of the true answer, I would expect to say "Hey that's incorrect", if they encountered an obviously mistaken quote.
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