Start Your Engines

[Ovyron]

Don't give up hope yet, the number I had in mind is wrong and we need to mutually agree on the right number next thursday and then adapt the ranking.

Hopefully actually on Thursday and not Wednesday so I get a chance to participate

Anyway, real men don't look at solutions, we find them ourselves, so I'll be sending mine without looking at Peer Trunz's post.

[leavenfish]

LOL!!

YOU mean your engines find them... 'real mean', of course, just use their own brain.

[Ovyron]

LOL!!

YOU mean your engines find them... 'real mean', of course, just use their own brain.

Sorry, wrong thread, you're looking for "Start Your Brain"

[Ovyron]

Okay, so after spending a good deal of time trying to pinpoint the exact shortest way to mate in Position 2 I realized that this isn't my thing, and that finding the best move problems are completely different from the grinding required by fastest mate solution. I have sent only my solution for the first position, and that's it for me.

Here's hoping that some future competition gets split, with Start Your Engines used exclusively for "find the best move" problems (with unique solutions, not those with many winning moves) and another for "find the shortest mate" competitions, that were fun once but get old fast.

Vytron,
Over and out.

[zullil]

Okay, so after spending a good deal of time trying to pinpoint the exact shortest way to mate in Position 2 I realized that this isn't my thing, and that finding the best move problems are completely different from the grinding required by fastest mate solution. I have sent only my solution for the first position, and that's it for me.

Here's hoping that some future competition gets split, with Start Your Engines used exclusively for "find the best move" problems (with unique solutions, not those with many winning moves) and another for "find the shortest mate" competitions, that were fun once but get old fast.

Vytron,
Over and out.

Finding the key move here and appreciating the theme of the composition are rewarding enough. I agree that finding the depth to mate is not much fun---which is why my computer is searching rather than me.

[Rebel]

Next week back to normal. Like I said at the start of week-4, let's shake the top of the tree a bit.

[Spliffjiffer]

after some more investigation im "absolutely" sure now that the line i gave above was suboptimal...so im happy that i didnt messed it up

[Vinvin]

I think that it may be interesting to see results of different engines in this competition.

I planned to do that after the next challenge (for the 12 first positions).

Here are the 12 positions from the 3 first weeks.

Code: Select all

Week-1 :
4rrk1/1bpR1p2/1pq1pQp1/p3P2p/P1PR3P/5N2/2P2PP1/6K1 w - - 0 0      
b2r3r/k4p1p/p2q1np1/NppP4/3p1Q2/P4PPB/1PP4P/1K1RR3 w - - 0 0      
5nr1/2Pp2pk/3Pp1p1/4P1P1/6P1/5K2/8/7n w - - 0 0      
4q2r/1b1kbp2/1p2p1p1/pP1pP1N1/P2P1PQP/3BK3/2R5/8 w - - 0 0      

Week-2 :
8/pP6/kpP3p1/brpPb1p1/1pP1PbP1/1P6/K5P1/8 w - - 0 0      
4R3/P7/2bB2p1/r3pk2/2p2p1P/2P2P1K/6P1/8 w - - 0 1      
4b1kn/3p1p1r/p2P1Ppr/p5Pp/p6P/p7/P7/7K w - -      
3r2k1/p6p/b2r2p1/2qPQp2/2P2P2/8/6BP/R4R1K w - - 0 0      

Week-3 :
1r6/4k3/r2p2p1/2pR1p1p/2P1pP1P/pPK1P1P1/P7/1B6 b - - 0 1      
6R1/8/2pB3k/2P4p/5p1q/5P2/4P1K1/8 w - - 0 0      
Rb6/1p4Pq/1p6/P2pR3/4p3/1K6/5P2/k7 w - - 0 1      
8/3P3k/n2K3p/2p3n1/1b4N1/2p1p1P1/8/3B4 w - - 0 0  

I'm trying to remember which engine is efficient for each position.

Sting-SF 9.6 is very fast for week 3. Timing on a 6*4GHz.
Position1 - type the move: 1...Rxb3+ (8 seconds for Sting-SF 9.6)
Position2 - type the move: 1.Bf8+ (around 1 minute for Sting-SF 9.6)
Position3 - type the move: 1.g8=Q (less than 1 second for Sting-SF 9.6)
Position4 - type the move: 1.Nf6+ (around 1 minute for Sting-SF 9.6)

[Ovyron]

Next week back to normal. Like I said at the start of week-4, let's shake the top of the tree a bit.

That should have been done by posting 4 really difficuly problems, not 4 really easy problems where it just takes a long time to get some exact "mate in X" solution, but that some engine eventually finds unassisted. No skills required.

That's called Fake Difficulty.

[Rebel]

It's thursday again, week-5 will be up within a couple of hours, but first this dreadful position-2 which in retrospect is not suited for a mate in x question.
[pgn][Event "Kubbel"]
[Site "?"]
[Date "1936"]
[White ""]
[Black ""]
[Result "1-0"]
[FEN "rk1b4/p2p2p1/1P6/2R2P2/8/2K5/8/5B2 w - - 0 0"]

1. Rc8+ Kxc8 2. Ba6+ Kb8 3. b7 Bb6 4. Kc4 Bf2 5. Kd5 Bg3 6. f6 gxf6 7. Ke4 Be5 8. Kf5 d5 ( 8... Bd4 9. Kg6 f5 10. Kf7 Bb6 11. Ke7 Kc7 12. bxa8Q Bc5+ 13. Ke8 Kd6 14. Bc4 Ke5 15. Qd5+ Kf4 16. Qxc5 a6 17. Be2 a5 18. Qd4+ Kg5 19. Kf7 a4 20. Qf2 a3 21. Qg3+ Kh6 22. Qg6# ) 9. Ke6 d4 10. Kd7 d3 11. bxa8Q+ Kxa8 12. Kc8 d2 13. Bb7# 1-0[/pgn]
It's a beautiful endgame study with an elegant mainline ending in a mate in 13 and with a more optimal defense a mate in 22, so I thought.... Until I discovered I had overlooked that black doesn't have to take the rook (1..Kxc8) but also can play 1..Kb7 which equals resignation after 2.Bg2+ which spoils the goal and fun to look for an exact mate in x.

---

Nevertheless 11 people have contributed and here is the division among the participants

Code: Select all

Mate  Number
33         1
23         2
15         1
27         3
82         1
36         1
xx         2 (abstained)

So what now? Preferable I would drop the position, give everyone 1 point for the trouble but that's unfair because some of you have put considerable (computer) time to get it right. Also after my own investigation I am inclined to think the 3 folks who contributed 27 are probably right. So I want to ask them to provide the analysis.

Anyway, the one (those) who is (are) right will receive 2 points.