Our Prize Problem contest, sponsored by Brian Hinkle, has ended. No, we can't offer the Nobel Prize, but Brian did offer $25 to the first person to solve it. He later upped his offer to $50, then $75, and finally $100.

But no one submitted a correct solution so Brian got to keep his money.

For those of you truly puzzled by the problem (which must be just about everyone), don't feel bad. The two most powerful computer engines in the world, KingsRow and Cake, couldn't solve it either! Here's Brian's solution and brief notes.

BLACK

WHITE
White to Play and Win

W:WK3,5,11,21,22,25,26,29,30,32:B1,2,4,10,12,16,19,20,23,28

3-7 10-15 7-10 20-24 21-17---A 24-27---B 11-7 2x11 10-6 1x10 22-18 15x31 17-14 10x17 25-22 17x26 5-1. White Wins.

A---Planning ahead for the fireworks.

B---16-20 25-21 24-27 11-7 2x11 30-25 23x30 32x7. White Wins.

WHITE

BLACK
Final Position, Black is Lost

B:WK1,29,30,32:B4,11,12,16,19,23,26,27,28,K31

White is down no less than six pieces, but still wins as Black will eventually run out of moves in this incredible block position. Marching the checkers on 11 and 4 down the main diagonal won't work as White will simply allow his piece on 29 to capture both of Black's approaching men. Try working through it on your own. You won't find a single variation in which Black doesn't eventually become completely blocked.

Block problems, along with fortress problems and "fugitive king" problems are notoriously difficult for computers to solve, and Grandmaster problemist Brian Hinkle has here created what may be the ultimate block problem of all time. We hope you enjoyed it as much as we did. In fact, if you'd like to see another Brian Hinkle classic, check out Bear Claw, published back in the early days of The Checker Maven.