Each row and column has exactly one A, one B, one C, and one D. In the following square, the outside letters show which letter is closest to the outside in that particular row or column. Fill the square!

       A   B   B       C
 +---+---+---+---+---+---+
A|   |   |   |   |   |   |
 +---+---+---+---+---+---+
 |   |   |   |   |   |   |D
 +---+---+---+---+---+---+
B|   |   |   |   |   |   |A
 +---+---+---+---+---+---+
C|   |   |   |   |   |   |D
 +---+---+---+---+---+---+
C|   |   |   |   |   |   |
 +---+---+---+---+---+---+
 |   |   |   |   |   |   |A
 +---+---+---+---+---+---+
   D       A   A   C

(In reply to My Solution by Bender)

Cool, haven't seen one of these with two spaces per line before! Has anyone got one with an even larger grid?

Bender stated:

"Here is my solution. There may be others..."

In case anyone is doubting the uniquness of the solution I would just like to confirm what Ken Haley has already stated, that the solution is definately unique. Further it is solvable by logic with no trial and error (as all good puzzles should be in my book.)

Cheers e.g.

Posted by Percy on 2005-10-17 19:46:24