I have multiplied two 3-digit numbers and coded the whole process twice:

In the 1st coding O replaces an odd digit and E the even.

   OOO
 * EOE
  OEOE
  OOO
 OEE  
 OOOEE 

In the 2nd coding S replaces a digit smaller than 6 and B a digit bigger than 5.

   SBB
 * SSB
  SSSB
  SSS
 BSB  
 BBSSB

Try to get my original numbers(digit 9 does not appear in the multiplication) and all other possible solutions, if any.

(In reply to re(2): computer solutons (spoilers) by Charlie)

1. All's well that ends well

2. Since the problem was created from the answer, I REALLY DID NOT KNOW A PRIORI THAT THE SOLUTION IS UNIQUE,
and you have proved it is.

Posted by Ady TZIDON on 2011-06-09 19:24:32