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by eplawless 6019 days ago
That was the first solution I had for #1. I'm currently at the following, but I think there has to be a better one because it's not clear that it would be possible.

G places the amulet in his safe, attaches his padlock and locks it with his key, then sends it to K, keeping his key. K receives G's safe, attaches his own padlock in addition to G's (there is a "large clasp", no mention of how large or how many padlocks it could support) and sends it back to G without sending his key. G removes his own padlock, and sends the chest back. K removes his padlock and has the amulet.

1 comments

I think your current solution is clearly the right one: It gives me the 'duh' moment.

Edit: But in real life the first solution might work better. Hard to imagine the henchmen who would be sure to spot you if you left your room even for a moment but would take no notice of servants shuffling back and forth three times with a [double-]padlocked safe.

reason it is unsatisfactiry (I had the same) is that one of the safe is not used, imo
It's a charasteristic of the real world that there are things not used in the solutions of the various problems that need to be solved.

It is one of the most brain-dead characteristics of school and university exams that one is not allowed to have extras - it's somehow "not fair."

I think not using some of the resources provided is perfectly reasonable.

apple and oranges, if the beauty of the problem is in a clean elegant solution that does not require all of the pieces, it is not a well posed riddle, or solution.

That's why the solution to the wolf-sheep-cabbage problem is not "just add more floating stuff so you can bring all at once, idiot".

The comparison to school and exams, appears unrelated to me: there are situations where external aid kills the point (e.g. calculator for arithemitic in firs grade).

Then I must not have explained myself clearly enough. I'm not talking about extra equipment, I'm talking about information that's not needed for the solution to the problem.

Recently (for some definition of "recent") I was setting an exam question. In it I gave various lengths, heights, and so on, and I was told that it was too hard because I gave details that weren't required. On the other hand, if one is given only the information required, there is already an artificial clue - all the information given must be used. That's unrealistic.

I've interviewed people for jobs who performed fantastically well on exam style questions, but when given free-form problems simply didn't know where to start.

For me, whether a solution is clean and elegant is independent of whether you've used all the information given. It's the solution itself that's elegant. It's not only plausible but likely that we have different concepts of elegance - I'm a mathematician. When solving math problems, real math problems such as required to get a PhD or publish a paper, there's no way you're given just the information required and no more.

Along those lines I've been moved to submit another puzzle - you can find it here:

http://news.ycombinator.com/item?id=1014092