🚀 go-pugleaf

Hi!

In article <binsun.6.000B40EB@mindspring.com>
binsun@mindspring.com (Sunjay Mohan) writes:

> I was wondering if anybody knows how to solve this problem:
>
> You are to use only four weights of integer value in pounds to be able to weigh objects from one to
>  forty pounds each on a balance beam scale. This means that one unknown weight 
> and a combination of the four weights described above can be placed on either 
> side of the scale.


It's "before breakfast" !!

The weights are 1, 3, 9, and 27.
Put the object on the left side, and put each weight on:
("L" means the left side, "R" the right side, "-" neither)

  |  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20
--+------------------------------------------------------------------
 1|  R  L  -  R  L  -  R  L  -  R  L  -  R  L  -  R  L  -  R  L
 3|  -  R  R  R  L  L  L  -  -  -  R  R  R  L  L  L  -  -  -  R
 9|  -  -  -  -  R  R  R  R  R  R  R  R  R  L  L  L  L  L  L  L
27|  -  -  -  -  -  -  -  -  -  -  -  -  -  R  R  R  R  R  R  R

  | 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
--+------------------------------------------------------------------
 1|  -  R  L  -  R  L  -  R  L  -  R  L  -  R  L  -  R  L  -  R
 3|  R  R  L  L  L  -  -  -  R  R  R  L  L  L  -  -  -  R  R  R
 9|  L  L  -  -  -  -  -  -  -  -  -  R  R  R  R  R  R  R  R  R
27|  R  R  R  R  R  R  R  R  R  R  R  R  R  R  R  R  R  R  R  R


--
SAITO Takaaki
takaaki@is.s.u-tokyo.ac.jp