送交者: Tangduoling 于 2005-4-16, 19:12:29:

回答: sorry incomplete post 由 Tangduoling 于 2005-4-16, 14:46:34:

for N balls
if N is strictly greater than (2 to the power of m) minus 4
and weakly less than (2 to the power of (m plus 1)) minus 4
Then weigh the balls m times and one can guarantee finding the defective ball. The way of doing it in the case where N=1020 is not much more intricated than the case where N=12.

ie. 2^m-4
<=2^(m+1)-4

加跟贴