回复：It is too eary to comment.

Good idea, if I were you I would not continue with the discussion about whether you made 'offensive' comments either. :)

OK, let's focus more on the question. Before that, I still need to make sure I understand you correctly. When you annouced your 2-question solution, it seems that you had quite some confidence in its correctness, reading from the title of the post:

• [大结局]2个问题的解法公布[续] -生肖迷宫- ♂

Now you say, that answer is not a 'absolute' one. '大结局' and yet not 'absolute'? ...Can we cut the chase and simply agree on that that solution you provided is a wrong one? -- otherwise, why bother try 1-question solution? because KangMM already provided a 0-question solution using that same method you presented.

For this type of problem with questions of binary answers, assuming there are N possibilities, you will need at least ceil(log_2(N)) questions. But that is a statment under normal assumption (for example, your questions have definite binary 'y' or 'n' answers -- or even more stictly, as ID94 pointed out, your questions should not be compound ones. At least, they should be without a implicit 'can-not-answer' as a third option as in your 2-question-solution). In this specific 3-fool problem, you label the 3 fools with A,B,C, there are totally 6 (=3!) possibilities, so under the normal assumption, you need at least 3 questions, even a 2-question solution does not exist. If you are not convinced, consider the following much easier problem: assume the 3 fools suddenly becomes 3 smarts and only give right 'y' or 'n', how many questions you need to id them?

Having said that, I will keep my mind open for solutions that will surprise me.

所有跟帖： 

• 最终答案公布，请见原贴 -生肖迷宫- ♂ (468 bytes) () 06/25/2008 postreply 14:55:27