At a glance you may think this is a draw. White wins!

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duncan
Posts: 12038
Joined: Mon Jul 07, 2008 10:50 pm

Re: At a glance you may think this is a draw. White wins!

Post by duncan »

Robert Flesher wrote:A beautiful position that illustrates the advantage that a single tempo can give. Then zugzwang and black is lost. The key to this position is looking at it yourself, before using an engine. It's very instructive! Some very strong engine(s) also struggle here. Komodo CCT after 5 min cannot see the win on my machine.



[D]4k3/5ppp/8/8/8/8/PPP5/3K4 w - - 0 1
tried it with finalgen. but leaves all white moves unsolved, except b3 and kc1 which is a win for black in 25

duncan
Robert Flesher
Posts: 1280
Joined: Tue Aug 18, 2009 3:06 am

Re: At a glance you may think this is a draw. White wins!

Post by Robert Flesher »

duncan wrote:
Robert Flesher wrote:A beautiful position that illustrates the advantage that a single tempo can give. Then zugzwang and black is lost. The key to this position is looking at it yourself, before using an engine. It's very instructive! Some very strong engine(s) also struggle here. Komodo CCT after 5 min cannot see the win on my machine.



[D]4k3/5ppp/8/8/8/8/PPP5/3K4 w - - 0 1
tried it with finalgen. but leaves all white moves unsolved, except b3 and kc1 which is a win for black in 25

duncan
Sometimes we need to leave the engines alone and move the pieces on a real board. :wink: I will say that a5 asap is the only way to win. For example Ke2 Kd7 Kf3 h5 a4 Kc6 a5 winning! As I explained the extra tempo leads to zugzwang. Black is lost! Perhaps final gen does not understand this.
Uri Blass
Posts: 10282
Joined: Thu Mar 09, 2006 12:37 am
Location: Tel-Aviv Israel

Re: At a glance you may think this is a draw. White wins!

Post by Uri Blass »

Robert Flesher wrote:
Uri Blass wrote:
Robert Flesher wrote:A beautiful position that illustrates the advantage that a single tempo can give. Then zugzwang and black is lost. The key to this position is looking at it yourself, before using an engine. It's very instructive! Some very strong engine(s) also struggle here. Komodo CCT after 5 min cannot see the win on my machine.



[D]4k3/5ppp/8/8/8/8/PPP5/3K4 w - - 0 1
Humans cannot calculate all possible lines so how looking at it by myself can help?

seeing the solution does not help to be able to practically win it because black can practically play a different move.

For example 1.Ke2 Ke7 or 1.Ke2 a5 or 1.Ke2 Kd7 2.Kf3 Kc6

Impossible to calculate all lines and if humans can understand that white wins then I would like to read some strategy that tells me what to do in every position and not a variation.
Hi Uri, I did not say calculate it youself. I said look at the position yourself without an engine. You of all people I thought would understand this. LOL, I guess not!. I studied and learned the secrets of this postion without an engine. I wanted people to move the pieces and try to understand this position. I guess this was the wrong place to post this.
I feel this position is too complex to understand it unless you start with something simpler.

Looking at the paper it is certainly not something that humans can solve in a few minutes and you need to understand many simpler positions first.

I like to think in chess but I am interested mainly in OTB tournaments when I cannot use hours to analyze some simpler positions that can happen later without calculating lines that tell me something about the original position.

Uri
Ignacio
Posts: 177
Joined: Wed Mar 08, 2006 8:15 pm

Re: At a glance you may think this is a draw. White wins!

Post by Ignacio »

On my Q6600 I have get:

FEN: 4k3/5ppp/8/8/8/8/PPP5/3K4 w - - 0 1

Deep Rybka 4.1 x64:

23+ 01:36 11.966.090 123.976 +0,12 Kd1-e2 h7-h5 c2-c4 h5-h4 Ke2-f3 f7-f5 b2-b4 Ke8-d7 b4-b5 g7-g5 c4-c5 g5-g4+ Kf3-f4 h4-h3 Kf4-g3 f5-f4+ Kg3-h2 Kd7-c8 c5-c6 Kc8-c7 a2-a3 g4-g3+ Kh2xh3 f4-f3 Kh3xg3 Kc7-b6 Kg3xf3 Kb6xb5 c6-c7
23+ 01:52 13.679.280 121.768 +0,27 Kd1-e2 h7-h5 c2-c4 h5-h4 Ke2-f3 f7-f5 b2-b4 Ke8-d7 b4-b5 g7-g5 c4-c5 g5-g4+ Kf3-f4 h4-h3 Kf4-g3 f5-f4+ Kg3-h2 Kd7-c8 c5-c6 Kc8-c7 a2-a3 g4-g3+ Kh2xh3 f4-f3 Kh3xg3 Kc7-b6 Kg3xf3 Kb6xb5
23+ 05:59 39.426.586 109.864 +6,27 Kd1-e2 h7-h5 c2-c4 h5-h4 Ke2-f3 f7-f5 b2-b4 Ke8-d7 b4-b5 g7-g5 c4-c5 g5-g4+ Kf3-f4 h4-h3 Kf4-g3 f5-f4+ Kg3-h2 Kd7-c8 c5-c6 Kc8-c7 a2-a3 g4-g3+ Kh2xh3 f4-f3 Kh3xg3 Kc7-b6 Kg3xf3 Kb6xb5
23+ 14:36 179.630.159 205.113 +12,67 Kd1-e2 h7-h5 c2-c4 h5-h4 Ke2-f3 f7-f5 b2-b4 Ke8-d7 b4-b5 g7-g5 c4-c5 g5-g4+ Kf3-f4 h4-h3 Kf4-g3 f5-f4+ Kg3-h2 Kd7-c8 c5-c6 Kc8-c7 a2-a3 f4-f3 Kh2-g3 Kc7-c8 a3-a4 Kc8-d8 b5-b6 Kd8-e7 Kg3xg4
23 19:25 267.324.050 229.419 +12,67 Kd1-e2 h7-h5 Ke2-f3 Ke8-d7 Kf3-g3 h5-h4+ Kg3xh4 Kd7-c6 b2-b3 Kc6-b5 c2-c3 g7-g6 a2-a4+ Kb5-c5 a4-a5 Kc5-b5 b3-b4 f7-f6 c3-c4+ Kb5-a6 Kh4-g3 f6-f5 Kg3-f3
24 21:29 303.539.037 235.519 +12,67 Kd1-e2 h7-h5 Ke2-f3 Ke8-d7 Kf3-g3 h5-h4+ Kg3xh4 Kd7-c6 b2-b3 Kc6-b5 c2-c3 g7-g6 a2-a4+ Kb5-c5 a4-a5 Kc5-b5 b3-b4 f7-f6 c3-c4+ Kb5xb4 a5-a6

Ignacio
syzygy
Posts: 5566
Joined: Tue Feb 28, 2012 11:56 pm

Re: At a glance you may think this is a draw. White wins!

Post by syzygy »

Robert Flesher wrote:Sometimes we need to leave the engines alone and move the pieces on a real board. :wink: I will say that a5 asap is the only way to win. For example Ke2 Kd7 Kf3 h5 a4 Kc6 a5 winning! As I explained the extra tempo leads to zugzwang. Black is lost! Perhaps final gen does not understand this.
I think it is safe to say that this position is far more complex that "a5 asap" and "the extra tempo leads to zugzwang". Sure, it is all about zugzwang, but the complexity is to such degree that mere mortals as opposed maybe to endgame specialists won't get very close to the solution from just "moving the pieces on a real board".

The article that was linked to might help though for gaining a real understanding of this position, I have not had a good enough look at it.
bob
Posts: 20943
Joined: Mon Feb 27, 2006 7:30 pm
Location: Birmingham, AL

Re: At a glance you may think this is a draw. White wins!

Post by bob »

syzygy wrote:
Robert Flesher wrote:Sometimes we need to leave the engines alone and move the pieces on a real board. :wink: I will say that a5 asap is the only way to win. For example Ke2 Kd7 Kf3 h5 a4 Kc6 a5 winning! As I explained the extra tempo leads to zugzwang. Black is lost! Perhaps final gen does not understand this.
I think it is safe to say that this position is far more complex that "a5 asap" and "the extra tempo leads to zugzwang". Sure, it is all about zugzwang, but the complexity is to such degree that mere mortals as opposed maybe to endgame specialists won't get very close to the solution from just "moving the pieces on a real board".

The article that was linked to might help though for gaining a real understanding of this position, I have not had a good enough look at it.
This is "wild7" on ICC. the way I learned to win this with white was to take a chess board with the white pawns and black king and play. And learn where the zugzwang happens. Once you recognize the positions where the king to move loses, you have it. The key becomes that white moves first. And it is all about maintaining that zugzwang tempo so that at the critical position, black can either push a pawn and lose it, or move the king and let a white pawn queen.
Robert Flesher
Posts: 1280
Joined: Tue Aug 18, 2009 3:06 am

Re: At a glance you may think this is a draw. White wins!

Post by Robert Flesher »

syzygy wrote:
Robert Flesher wrote:Sometimes we need to leave the engines alone and move the pieces on a real board. :wink: I will say that a5 asap is the only way to win. For example Ke2 Kd7 Kf3 h5 a4 Kc6 a5 winning! As I explained the extra tempo leads to zugzwang. Black is lost! Perhaps final gen does not understand this.
I think it is safe to say that this position is far more complex that "a5 asap" and "the extra tempo leads to zugzwang". Sure, it is all about zugzwang, but the complexity is to such degree that mere mortals as opposed maybe to endgame specialists won't get very close to the solution from just "moving the pieces on a real board".

The article that was linked to might help though for gaining a real understanding of this position, I have not had a good enough look at it.
Once you study it infact it is that simple. I can beat ANY engine with ease playing the white pieces. So can anyone, but it requires some study. This is no different than learning Queen vs Rook in that it takes alot of study to be able to do it correctly. There are many different rank defense that the rook can adopt. However, once you have studied it enough it all comes together. Try it before you claim it to be to difficult, you may be surprised.
Robert Flesher
Posts: 1280
Joined: Tue Aug 18, 2009 3:06 am

Re: At a glance you may think this is a draw. White wins!

Post by Robert Flesher »

bob wrote:
syzygy wrote:
Robert Flesher wrote:Sometimes we need to leave the engines alone and move the pieces on a real board. :wink: I will say that a5 asap is the only way to win. For example Ke2 Kd7 Kf3 h5 a4 Kc6 a5 winning! As I explained the extra tempo leads to zugzwang. Black is lost! Perhaps final gen does not understand this.
I think it is safe to say that this position is far more complex that "a5 asap" and "the extra tempo leads to zugzwang". Sure, it is all about zugzwang, but the complexity is to such degree that mere mortals as opposed maybe to endgame specialists won't get very close to the solution from just "moving the pieces on a real board".

The article that was linked to might help though for gaining a real understanding of this position, I have not had a good enough look at it.
This is "wild7" on ICC. the way I learned to win this with white was to take a chess board with the white pawns and black king and play. And learn where the zugzwang happens. Once you recognize the positions where the king to move loses, you have it. The key becomes that white moves first. And it is all about maintaining that zugzwang tempo so that at the critical position, black can either push a pawn and lose it, or move the king and let a white pawn queen.
A perfect explanation!
jd1
Posts: 269
Joined: Wed Oct 24, 2012 2:07 am

Re: At a glance you may think this is a draw. White wins!

Post by jd1 »

Robert Flesher wrote:A beautiful position that illustrates the advantage that a single tempo can give. Then zugzwang and black is lost. The key to this position is looking at it yourself, before using an engine. It's very instructive! Some very strong engine(s) also struggle here. Komodo CCT after 5 min cannot see the win on my machine.



[D]4k3/5ppp/8/8/8/8/PPP5/3K4 w - - 0 1
Thanks for posting, it is a really fascinating endgame!! The latest development version of Toga II (downloadable at the Toga Developers Discussion Board btw) takes 4.2 billion nodes(!) to find 1. Ke2 with a plus score without EGBBs:

Toga280513_Intel:
26/84 39:06 3,006,287,931 1,281,428 0.00 a2-a4 h7-h5 a4-a5 Ke8-d8 Kd1-e2 h5-h4 c2-c4 Kd8-c7 c4-c5 Kc7-b7 Ke2-f3 f7-f5 Kf3-f2 Kb7-b8 Kf2-g2 f5-f4 Kg2-g1 Kb8-b7 Kg1-g2 Kb7-b8
26/84+ 54:14 4,271,812,049 1,312,753 +1.28 Kd1-e2 h7-h5 Ke2-f3 Ke8-d7 a2-a4 Kd7-c6 a4-a5 Kc6-b7 b2-b4 Kb7-a6 Kf3-g3 g7-g5 c2-c4 h5-h4+ Kg3-h3 f7-f5 c4-c5 Ka6-b5 Kh3-h2 g5-g4 Kh2-g2 h4-h3+ Kg2-g3 f5-f4+ Kg3-h2 f4-f3 Kh2-g3 f3-f2 Kg3xf2 h3-h2 Kf2-g2 g4-g3 Kg2-h1 Kb5-c6 a5-a6 Kc6-d7 b4-b5 Kd7-c7 c5-c6 Kc7-b6 Kh1-g2 Kb6-c7
Arpad Rusz
Posts: 273
Joined: Sat Apr 17, 2010 2:34 pm
Location: Budapest

Re: At a glance you may think this is a draw. White wins!

Post by Arpad Rusz »

You are right that FinalGen cannot solve this endgame. It seems that the software cannot handle minor promotions (except if the promoted piece is captured immediatelly after promotion). The win in this endgame depends on a position where black promotes to a knight (and the knight survives after the promotion)! How black achieves a minor promotion? Starting from the following critical position

[D]8/8/8/PkP5/1P4p1/5pKp/8/8 b - - 0 1

black plays 1...h2! 2.Kh2 Kc4! 3.c6 Kd3 4.c7 f2 5.c8Q f1N+!! (and not 5...f1Q?! 6.Qa6+ +-) leading to a position which is unknown to Finalgen. One can simply realize that this position is also lost by black (but manages to trick FinalGen).

Fortunatelly there is already a version of FinalGen which allows to manually set some positions' value before starting the generation process:
http://www.mtu-media.com/finalgen/oldve ... _Setup.zip

If one sets the critical position's value to DRAW, FinalGen reports a win for 1.Ke2 and 1.Ke1.
(1.a4, 1.b4, 1.c4 still remain unsolved by FinalGen. So further critical positions should be set to have a full solution with this software. Should these moves lead to draws or wins?)