That is a very hard problem. I managed to figure out weighings 1 and 3 but could not complete that middle step. This is not a binary search, it is an exhaustive search.
On Mar 7, 2013, at 4:35 PM, Joe Niederberger <firstname.lastname@example.org> wrote:
> By the way, the twelve coin problem is a real classic -- my father told me it when I was about 10. > Its easy enough to find a solution using Google, but as a courtesy to those who want to tough it out - please don't post a real solution here without the word "SPOILER" up front! > > Cheers, > Joe N