We've always liked those World War Two inspirational posters which urged American citizens to do their all and give their best in support of the war effort. The poster above warns of the dangers of aiding the enemy through carelessness and emphasizing the need to get things right the first time.
That surely applies to our game of checkers, where carelessness can indeed cede the day to our opponent, and we may have one and only one opportunity to "get it right" and find a win or a draw.
In the following situation, Black has one and only one move to draw. He has to get it right the first time as there won't be a second chance.
B:W13,16,18,22,25,28,30,32:B1,3,5,6,8,9,11,20
The position is more of a practical exercise than a contest-grade problem, but we think it's worthy of study. Will you get it right on your first try, or will it take a couple of tries? Unlike in an over the board contest, you can try as many times as you wish, and when you're ready, one try at clicking your mouse on Read More will bring you to the solution.
Solution
In the play below, many variations are possible except for the first move, which is Black's only drawing chance. From there on, both players have to be careful and some seemingly natural looking moves lead to a loss. It's an interesting position and worth exploring various alternative play with your computer.
1. | 8-12* | 16x7 |
2. | 3x10 | 30-26 |
3. | 10-14 | ... |
Or 12-16.
3. | ... | 18-15 |
4. | 14-17 | 15-10! |
This move leads to a clearance and makes the draw clearer. White has had to play correctly as well as Black.
5. | 6x15 | 13x6 |
6. | 1x10 | 22x13 |
The draw is assured with proper care. Further play might go as follows.
7. | 15-19 | ... |
15-18 loses!
7. | ... | 25-22 |
8. | 10-14 | ... |
10-15 loses!
8. | ... | 13-9 |
9. | 14-18 | 22x15 |
10. | 5x14 | 15-11 |
11. | 12-16 | 11-8 |
12. | 14-17 | ... |
14-18 loses!
12. | ... | 8-4 |
13. | 17-21 | 26-22 |
14. | 21-25 | 22-18 |
15. | 25-30 | 18-15 |
16. | 20-24 | 15-11 |
17. | 24-27 | 32x23 |
18. | 19x26 | ... |
A clear draw. Thanks to Lloyd and "Gosh Josh" Gordon who provided this position from one of their many spiritedly contested games.