Summarize because it is a good subject for discussing the state of knowledge - Efficiency of coin search 2011 - Explaining that the efficiency can change by a factor of 10 or more depending on how you look for it (i.e., the algorithm) and that it becomes instantly more difficult when there may be multiple fake coins (the lecture is given in the context of debugging, so it is important to notice it as soon as possible). - Efficient trial and error 2017-09-05

https://www.facebook.com/1129148772/posts/10222591132543559?d=n&sfns=mo

I’m suddenly curious about the pattern of the minimum number of moves per problem in the “there are M fake coins among N coins, and the fake coins are (a little heavy|not sure if they are heavy or light)” problem (why would I be curious about that at the end of a holiday weekend instead of the first day of a holiday weekend…) 2020-08-11

  • Various variations of the problem
  • Finding a solution when there is more than one

2021-04-25 https://www.facebook.com/nishiohirokazu/posts/10224642622509526

  • 2 out of 10 heavy fake coins. →Now that we know that the worst-case scenario can be determined in 4 moves when the number of cards is 2 out of 10, let’s try “1 to 3 out of 80” which I couldn’t solve 10 years ago. →I was still difficult for me even with “80 coins and 2 heavy coins”.

Next state when compared separately for N, N, and M


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