or a new answer, i think this one is correct: They decide to go one time to the cliff for every single monk. If they the number of days is equal to the number of monks with dots they see, they have to jump.
Let's take it from here. How do you come to this conclusion - that the number of days is equal to the number of dots seen by the ones who have a dot?
Suppose there are 2 monks with a dot. On day 1, those two monks each see 1 dot. How could either monk know, by seeing one monk with a dot, whether he has a dot or not himself?...
(You're almost there though, you know <img src="/ubbthreads/images/graemlins/winkwink.gif" alt="" /> )
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