I bought a new calculator at the Dollar Store and, sure enough, it’s defective. After some trial and error with it, I discovered that each digit in the display contained the same two pairs of elements (out of the seven elements labeled A to G below) that were somehow ‘crosswired’. That is, if one element was called upon to illuminate, its partner would illuminate instead. If both were supposed to illuminate, neither would! For example, if A/D and B/F were the faulty pairs, the number 3 would simply display as F/G/C, as illustrated below.
Based on the illuminated elements for each digit given below, find the faulty pairs to then solve the following 3digit by 2digit multiplication:
 C/D  F/B/G/E/C  G/E/C 
X   F/G/C/D  F/G/E/C/D 
F/E/C/D  F/G/C/D  F/G/E/C/D  F/E/C/D 
(In reply to
re(5): problems with computer program by rod hines)
rod, the bottom line on why my program failed is that I was looking at all the possible pairs of pairs of failing elements, to see what the resulting set of elements would be for any given digit and then looking for those sets of elements to convert back to digits, and then check that the resulting multiplication was valid.
However all my transformed sets of elements were based on the original set of elements to represent 7 being A/B/C, while the solution required that the original representation of 7 be A/B/C/F.

Posted by Charlie
on 20090219 17:16:11 