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A comment on The Logic Puzzle You Can Only Solve with Your Brightest Friend.

Re:The Logic Puzzle You Can Only Solve with Your Brightest F... by ggambetta on Tuesday July 17, 2018 @07:08AM (#17548789)
I think the puzzle isn't specified well enough. Critically, it doesn't say that your friend knows whether you passed or not when you're asked, and this is a central part of the proposed solution:

> First, you and your friend have to realize that each “pass” counts as a signal.

But the spec only says

> The caretaker asks you each one at a time, once a day, and you can choose to answer or to pass. Both of you know that you’re always asked first. If you both pass on a given day, the question [...] is posed to each of you again the next day, and the next, and so on, until you get it right or wrong.

Also, "both of you know that you’re always asked first" could have been written in a less confusing way, e.g. "both of you know who is asked first".

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Re:The Logic Puzzle You Can Only Solve with Your Brightest F... by Aardwolf on Tuesday July 17, 2018 @10:11AM (#17549834)
I was especially annoyed by the "*" pointing to a footnote in the problem description, where you then had to scroll over the spoilers to read the footnote
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Re:The Logic Puzzle You Can Only Solve with Your Brightest F... by skrebbel on Tuesday July 17, 2018 @07:16AM (#17548825)
Not true. You're always asked first. If you had not passed, then your friend would be either freed or locked up forever (thus not asked at all).
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Re:The Logic Puzzle You Can Only Solve with Your Brightest F... by ggambetta on Tuesday July 17, 2018 @07:25AM (#17548857)
This assumes the caretaker uses short-circuit evaluation :) It's a reasonable assumption to make, but I'd still argue the problem is under-specified.
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Re:The Logic Puzzle You Can Only Solve with Your Brightest F... by neogodless on Tuesday July 17, 2018 @09:33AM (#17549593)
I thought what you thought at first, but I re-read it, and it's quite clear. Especially this second sentence.

> The only way for you both to escape is for one of you to give the total number of visible statues. Get it wrong, and neither of you ever leave.

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Re:The Logic Puzzle You Can Only Solve with Your Brightest F... by BoiledCabbage on Tuesday July 17, 2018 @11:41AM (#17550441)
That doesn't break the puzzle at all. Odd days you take the option to answer while your friend agrees to always pass. Even days vice versa. By that interpretation it doubles the days to answer, but the process is identical.
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