On the 4x4 board below, two white and two black queens are placed so that no queens of one color attack any queen of the other color.

Q Q Q Q

Find a way to place 9 white queens and 9 black queens on an 8x8 chessboard in a similar fashion.

(In reply to No Subject by ed bottemiller)

Is this a better visual for your solution, Ed?

+---+---+---+---+---+---+---+---+
|   |   | Q | Q | Q |   |   |   |
+---+---+---+---+---+---+---+---+
|   |   |   | Q | Q |   |   |   |
+---+---+---+---+---+---+---+---+
| Q |   |   |   | Q |   |   |   |
+---+---+---+---+---+---+---+---+
| Q |   |   |   |   |   |   |   |
+---+---+---+---+---+---+---+---+
| Q |   |   |   |   |   |   |   |
+---+---+---+---+---+---+---+---+
|   |   |   |   |   | q | q |   |
+---+---+---+---+---+---+---+---+
|   | q |   |   |   | q | q | q |
+---+---+---+---+---+---+---+---+
|   | q |   |   |   |   | q | q |
+---+---+---+---+---+---+---+---+

Posted by Dej Mar on 2008-03-25 10:59:15