Monday, February 20, 2006

The fastest suicide checkers loss?

I've been playing around a bit with my book generator for suicide checkers because of the upcoming match against the Canadians. I was looking at early losses in suicide checkers, and this is the earliest I found so far:

1. 10-15 22-17 2. 6-10 23-19??

Red to move and win! Can you solve it? Can you find a faster way to lose a game of suicide checkers?

5 comments:

Zadius said...

Here's a very short game. Is this what you're looking for?

12-16 24-19 10-15 19x10 7x14 22-17 3-7 17x3 2-7 3x19 4-8 23-18 9-14
18x2 1-6 2x9 5x14 28-24 11-16 19x17

Martin Fierz said...

Hi Zadius,

that's not what I'm looking for: your game is "flawed" in the sense that white is actively helping red to win (e.g. 21-17 instead of 28-24 on 2nd-last move wins for white). I'm looking for the earliest proven loss. In the game I posted, that is after the 2nd move of white - from then on, the game is lost.

cheers
Martin

Zadius said...

Ah, OK.

I'm not very good at suicide checkers but I'll give it a shot:

1. 10-15 22-17 2. 6-10 23-19 3. 10-14 17x10 4. 7x14 19x10 5. 1-6 10x1 6. 2-6 1x17 7. 9-14
17x10 8. 3-7 10x3 9. 12-16 3x19 10. 11-16 19x12 11. 4-8 12x3 12. 5-9 3-7 13. 9-13 7-11 14. 13-17 21x14 *

Zadius said...

I realized I made a big mistake there because instead of 17x10 white could do 19x10. That was silly, but I went back to the drawing board and tried this:
1. 10-15 22-17 2. 6-10 23-19 3. 10-14 19x10 4. 1-6 10x1 5. 2-6 1x10 6. 11-15 10x19 7. 12-16 19x12 8. 7-11 17x10 9. 3-7 10x3 10. 11-16 12x19 11. 9-13 3x12 12. 4-8 12x3 13. 13-17 21x14 14. 5-9 14x5 *

Martin Fierz said...

Well solved, Zadius! The line in your first post with 7...17x10 is one of the reasons why suicide checkers is tough to program: In general, it is good to win material, but there are also positions where you can be lots of material up in a "quiet" position, like here, before 12. 5-9 - and still lose. In regular checkers, I can stop the search in such positions, but in suicide checkers that isn't possible.