There are N=2^n bags of rice looking alike, N-1 of which have equal weight and one is slightly heavier. The weighing balance is of unlimited capacity. Using the balance, the minimum number of weighing required to identify the heavier bag is?
Solution Stats
Problem Comments
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3 Comments
@bmtran (Bryant Tran)
on 31 Dec 2012
I think it only takes 5 weighings when N=128. Am I incorrect?
Alfonso Nieto-Castanon
on 31 Dec 2012
agree 5 weighing for N=128 (worst case scenario you reduce to 43 15 5 2 1 after each consecutive weighing)
trekker
on 2 Jan 2013
the last test case provided by the author is wrong: should be 5 since log(128)/log(3) < 5.
Solution Comments
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1 Comment
Dan
on 8 Jan 2013
Correct the test suite
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