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.

Let's try:

..QQQ...

...QQ...

Q...Q...

Q.......

Q.......

.....qq.

.q...qqq

.q....qq

Sorry, I don't have a way to present this in a better graphic. (Q are one color, q the other).

Posted by ed bottemiller on 2008-03-25 10:32:46