The a5 atom smasher

[Dann Corbit]

[d]8/p5k1/1p1r4/2pB4/P1P5/5PKP/6P1/8 b - -
Yes, I know that a computer will crush the life out of this position in a fraction of a second.
But as a human is it immediately obvious that a5 is the winning move?
From a Ling Diren game.

[Pio]

[d]8/p5k1/1p1r4/2pB4/P1P5/5PKP/6P1/8 b - -
Yes, I know that a computer will crush the life out of this position in a fraction of a second.
But as a human is it immediately obvious that a5 is the winning move?
From a Ling Diren game.

I understand it but would not have considered it. I think I would have played a6. Would that work as well?

[Dann Corbit]

[d]8/p5k1/1p1r4/2pB4/P1P5/5PKP/6P1/8 b - -
Yes, I know that a computer will crush the life out of this position in a fraction of a second.
But as a human is it immediately obvious that a5 is the winning move?
From a Ling Diren game.

I understand it but would not have considered it. I think I would have played a6. Would that work as well?

Draw.
Original position:
[d]8/p5k1/1p1r4/2pB4/P1P5/5PKP/6P1/8 b - - acd 36; ce 411; acs 26; acn 403681; pv a5 Be4 Rd4 Bd5 Kg6 h4 Kf6 h5 Kg5 Bc6 Rxc4 Kf2 Kxh5 Ke3 Kg5 g4 Rd4 Bb5 Rd5 Bc6 Re5+ Kd3 Re1 Kc4 Rc1+ Kd3 Kf4 Be4 Rd1+ Kc2 Rd4 Bc6 Ke5 Bb5 Rb4 Kc1 Rf4 Bc6 Rc4+ Kd2 Rd4+ Ke3 Rb4 Kd2 Kf4 Kc1 Rc4+ Kb2 ; bm a5;

After a6:
[d]8/6k1/pp1r4/2pB4/P1P5/5PKP/6P1/8 w - - acd 36; ce 0; acs 1; acn 23091; pv Kf4 b5 axb5 axb5 Ke5 Rb6 cxb5 Rxb5 Be4 Rb2 g3 c4 Kd4 c3 Kxc3 Rh2 f4 Rxh3 ; bm Kf4;

After a5:
[d]8/6k1/1p1r4/p1pB4/P1P5/5PKP/6P1/8 w - - acd 36; ce -425; acs 17; acn 268853; pv Be4 Rd4 Bd5 Kg6 h4 Kf6 h5 Kg5 f4+ Rxf4 h6 Rh4 Bb7 Rxh6 Kf3 Rf6+ Ke2 Rf4 Bd5 Rd4 Ke3 Kg4 Bf3+ Kg3 Bd5 Rh4 Be4 Rh1 Bc6 Rc1 Bd5 Re1+ Kd3 Kf4 Kd2 Ra1 Bc6 Ra2+ Kc3 Ke5 Kb3 Re2 Kc3 Re3+ Kd2 Kd4 ; bm Be4;

[Pio]

[d]8/p5k1/1p1r4/2pB4/P1P5/5PKP/6P1/8 b - -
Yes, I know that a computer will crush the life out of this position in a fraction of a second.
But as a human is it immediately obvious that a5 is the winning move?
From a Ling Diren game.

I understand it but would not have considered it. I think I would have played a6. Would that work as well?

Draw.
Original position:
[d]8/p5k1/1p1r4/2pB4/P1P5/5PKP/6P1/8 b - - acd 36; ce 411; acs 26; acn 403681; pv a5 Be4 Rd4 Bd5 Kg6 h4 Kf6 h5 Kg5 Bc6 Rxc4 Kf2 Kxh5 Ke3 Kg5 g4 Rd4 Bb5 Rd5 Bc6 Re5+ Kd3 Re1 Kc4 Rc1+ Kd3 Kf4 Be4 Rd1+ Kc2 Rd4 Bc6 Ke5 Bb5 Rb4 Kc1 Rf4 Bc6 Rc4+ Kd2 Rd4+ Ke3 Rb4 Kd2 Kf4 Kc1 Rc4+ Kb2 ; bm a5;

After a6:
[d]8/6k1/pp1r4/2pB4/P1P5/5PKP/6P1/8 w - - acd 36; ce 0; acs 1; acn 23091; pv Kf4 b5 axb5 axb5 Ke5 Rb6 cxb5 Rxb5 Be4 Rb2 g3 c4 Kd4 c3 Kxc3 Rh2 f4 Rxh3 ; bm Kf4;

After a5:
[d]8/6k1/1p1r4/p1pB4/P1P5/5PKP/6P1/8 w - - acd 36; ce -425; acs 17; acn 268853; pv Be4 Rd4 Bd5 Kg6 h4 Kf6 h5 Kg5 f4+ Rxf4 h6 Rh4 Bb7 Rxh6 Kf3 Rf6+ Ke2 Rf4 Bd5 Rd4 Ke3 Kg4 Bf3+ Kg3 Bd5 Rh4 Be4 Rh1 Bc6 Rc1 Bd5 Re1+ Kd3 Kf4 Kd2 Ra1 Bc6 Ra2+ Kc3 Ke5 Kb3 Re2 Kc3 Re3+ Kd2 Kd4 ; bm Be4;

Thank you Dann! After looking at the position more I would have thought my suggestion would have lost but would have won with white king on h2. A really nice position and a position my bad chess engine would not understand . I guess if I implemented some simple heuristic to see if the king could take a passed pawn it would understand it very quickly. A nice position that I will use

[Dann Corbit]

I am finding a lot of fun positions from the Ding Liren games.
Right now, I am analyzing every move he has ever played (along with those of his opponents in those games).

Two more beauties:
[d]r4r1k/1bp1qppp/p4n2/2b1p3/Pp2P2Q/1B5P/1PPN1PP1/R1B1R1K1 b - - acd 36; ce 188; acs 132; acn 1294000; pv g5 Qxg5 Rg8 Qf5 Rg7 Nf1 Rg6 g3 Bd4 h4 Nxe4 Rxe4 Rf6 Rxe5 Qd6 Bf4 Rxf5 Rxf5 Qc6 Rd5 Qb6 Be5+ Bxe5 Rxe5 Qf6 Re3 Qxb2 Rd1 Qf6 Rd7 Qc6 Rd5 Re8 Rxe8+ Qxe8 Rd4 c5 Rf4 Qc6 f3 f6 Ne3 Qd7 Rxf6 Qd4 Re6 h5 Re7 Bc6 Kh2 Bxf3 ; bm g5;

[d]1r6/7p/1bR2pk1/1PN2b2/1KP5/1P3r2/3R1P1P/8 w - - acd 36; ce 310; acs 66; acn 801987; pv Rxb6 Rxb6 Rd8 Kf7 Ka5 Re6 b6 Re7 b4 Rf4 b7 Rxb7 Nxb7 Rxc4 Nd6+ Ke7 Nxc4 Kxd8 Kb6 Bd3 Na3 Kd7 b5 Kd6 Ka7 Bxb5 Nxb5+ Kc6 Nc3 f5 Kb8 h6 h4 Kd6 Kb7 Ke5 Kc7 Kf4 Kd6 Kf3 Ke5 f4 ; bm Rxb6;

P.S.
SF also liked a6 for a while, so you are in good company:

Code: Select all

Searching: 8/p5k1/1p1r4/2pB4/P1P5/5PKP/6P1/8 b - - 0 1
infinite: 0 time: 0 increment: 0 moves to go: 0

 1   +0.06   00:00    4851  Rg6+ Kf2 
 2   -0.25   00:00   29475  Rd8 h4 
 3   -0.39   00:00   60029  Rg6+ Kh2 Rf6 g3 
 4   -0.41   00:00   89103  Rh6 h4 Rh8 f4 
 5   -0.44   00:00  115183  Rd8 Kf4 Re8 h4 Re2 
 6   -0.41   00:00  142534  Rd8 h4 Re8 Kf2 Rh8 g3 
 7   -0.48   00:00  174944  Rd8 h4 Re8 Kf2 Rh8 g3 Kf6 
 8   -0.27   00:00  201913  Rd7 Kf4 Re7 g3 Re1 g4 Ra1 
 9   -0.38   00:00  230744  Rd7 Kf4 Re7 g4 Re2 h4 Ra2 g5 Kg6 
10   -0.22   00:00  285727  a6 Kf4 Kf6 Ke4 Rd8 h4 Rh8 g3 
11   -0.59   00:00  344264  a6 Kf4 Kf6 Ke4 Rd7 h4 Rh7 g3 Re7+ Kf4 Rh7 Be4 Rh8 Bb7 a5 
12   -0.39   00:00  381878  a6 Kf4 b5 Ke5 Rb6 axb5 axb5 cxb5 Rxb5 Ke6 Rb6+ Kf5 Rb4 g4 Rd4 
13   -0.21   00:00  472925  Rg6+ Kh2 Rd6 g4 a6 Bb7 a5 h4 Rd3 Kg3 Rc3 Bd5 Ra3 
14   +0.00   00:00  535145  Rg6+ Kh2 Rd6 Kg3 
15   -0.00   00:00  615816  Rg6+ Kh2 Rd6 Kg3 
16   +0.00   00:00  782522  Rg6+ Kf2 Rh6 Kg3 Kf6 f4 Kf5 Kf3 Kf6 
17   +0.00   00:00  966559  Rg6+ Kf2 Rh6 f4 Kf6 Kf3 Rh7 Kg3 Kf5 Kf3 
18   -0.00   00:00   1302K  Rg6+ Kf2 Rh6 f4 Kf6 Kg3 Kf5 Kf3 Kf6 Kg4 Rg6+ Kf3 
19   +0.00   00:00   1480K  a6 Kf4 b5 Ke5 Rb6 axb5 axb5 cxb5 Rxb5 Kd6 Rb2 g3 Rh2 h4 Rh3 Kxc5 Rxg3 
20   +0.00   00:00   1634K  a6 Kf4 b5 Ke5 Rb6 axb5 axb5 cxb5 Rxb5 Kd6 Rb2 g3 Rh2 h4 Rh3 Kxc5 Rxg3 
21   +0.00   00:00   2016K  a6 Kf4 b5 axb5 axb5 Ke5 Rb6 cxb5 Rxb5 Kd6 Rb2 g3 Rh2 h4 Rh3 Kxc5 Rxg3 
22   +0.00   00:00   2294K  a6 Kf4 b5 axb5 axb5 Ke5 Rb6 cxb5 Rxb5 Kd6 Rb2 g3 Rh2 h4 Rh3 Kxc5 Rxg3 
23   +0.09   00:00   4035K  a5 Be4 Kf6 h4 Rd4 Bd5 Rd2 Bc6 Rd1 Kh3 Kf5 g4+ Kf4 Kg2 Rc1 Bd5 Ra1 Bc6 Ra2+ Kh3 Rc2 Bd5 
24   +0.07   00:00   7086K  a5 Be4 b5 cxb5 Rd4 Bc2 Rb4 f4 Rb2 Be4 Ra2 b6 Rxa4 Bc6 Rb4 b7 Kf6 h4 a4 Bxa4 Rxb7 Kf3 Rh7 g4 Rxh4 g5+ Kf5 Bc2+ Ke6 Bb3+ Kd6 Bc4 Ke7 Bb5 Rh3+ Ke4 Rg3 
25   +0.39   00:00  10230K  a5 Be4 b5 cxb5 Rd4 Bc2 Rd2 Be4 Ra2 b6 Rxa4 b7 Rb4 Bc6 Kf6 h4 a4 Bxa4 Rxb7 Bc6 Rb2 Be4 c4 f4 c3 Kf3 Rb4 Bd3 
26   +1.05   00:02  29421K  a5 Be4 Kf6 h4 Rd4 Bd5 Kg7 h5 Rd2 Bc6 Kh6 Be8 Rd4 Bf7 Kg5 Kf2 Rf4 Bd5 Kxh5 g3 Rd4 f4 Kg6 Kf3 Rd3+ Kg4 
27   +1.15   00:03  39538K  a5 Be4 Kh8 h4 Rd4 Bd5 Kg7 h5 Rd2 Bc6 Kh6 Be8 Rd4 Bf7 Kg5 Kf2 Rd2+ Kg1 Rb2 Kh2 Rb4 f4+ Kf6 Bd5 b5 axb5 a4 h6 a3 h7 
28   +1.62   00:04  56789K  a5 Be4 Kh6 Kf4 Rd4 Ke5 Rxc4 Bc6 Rc2 g3 Rh2 h4 Rh3 g4 Rxh4 Kf6 Kh7 Bb5 Kh8 Ke5 Kg7 Kd6 Rh1 f4 Ra1 Ke5 Rb1 f5 Rxb5 axb5 a4 f6+ Kf8 Ke4 a3 
29   +1.89   00:06  86151K  a5 Be4 Kh8 h4 Rd4 Bd5 Kg7 h5 Kh6 Kh3 Kxh5 g4+ Kg5 Kg3 Rd3 Be4 Ra3 Bc6 Rc3 Bd5 Rb3 Bc6 Ra3 Bd7 Rc3 Bb5 Rd3 Bc6 Kf6 Kh4 Rd2 Be4 Ke5 Kg3 Rd4 Bd5 Rf4 Be4 Rf8 
30   +1.99   00:07 101287K  a5 Be4 Kh6 h4 Rd4 Bd5 Kg7 h5 Kh6 Kh3 Kxh5 g4+ Kg5 Kg3 Rd3 Be4 Ra3 Bc6 Rc3 Bd5 Rb3 Bc6 Ra3 Bd7 Rc3 Bb5 Rd3 Bc6 Kf6 Kh4 Rd2 Kg3 Rd4 Bd5 Ke5 Kf2 Rd3 Kg3 Ra3 Bc6 Rb3 Bd5 Rd3 Bc6 Ra3 
31   +2.01   00:07 110223K  a5 Be4 Kh6 h4 Rd4 Bd5 Kg7 h5 Kh6 Kh3 Kxh5 g4+ Kg5 Kg3 Rd3 Be4 Ra3 Bc6 Rc3 Bd5 Rb3 Bc6 Ra3 Bd7 Rc3 Bb5 Rd3 Bc6 Kf6 Be4 Ra3 Bc6 Rc3 Bd5 Kg5 Be6 Rd3 Bd5 Rd4 Be6 Kf6 Bd5 Ke5 
32   +2.61   00:13 200755K  a5 Be4 Kh6 Kf2 Rd4 Bc6 Rxc4 Ke3 Rc3+ Kd2 Ra3 g3 Ra2+ Ke3 Rg2 g4 Rh2 h4 Rxh4 Bb5 Kg5 Bd7 Rh3 Ke4 Rg3 f4+ Kg6 g5 c4 Bb5 c3 Bd3 Kg7 Bc2 Rg1 Kd3 Rg4 Kxc3 Rxf4 Kb2 
33   +2.82   00:20 288446K  a5 Be4 Kf6 h4 Rd4 Bd5 Kg7 Bc6 Rxc4 Kf2 Rc2+ Kf1 Kf6 g4 Rh2 h5 Kg5 Bb5 Rc2 Ke1 c4 Kd1 Rf2 Bxc4 Rxf3 Kc2 Rf4 Bb5 Rd4 Kc3 Rxg4 Be8 Rh4 Kb3 Rf4 Kc2 Rc4+ Kb2 
34   +3.24   00:26 386860K  a5 Be4 Kf6 Kf4 Rd4 Ke3 Rxc4 Bc6 Rc2 g4 Rh2 h4 Rxh4 Bb5 Rh3 Ke4 Rg3 Kf4 Rg1 Bd3 Rd1 g5+ Kg7 Ke3 Re1+ Kf4 Ra1 Bb5 Rb1 Ke3 Rb3+ Ke4 Rb4+ Ke3 Kg6 f4 Kf7 f5 Rg4 g6+ Kg7 Kf3 
35   +3.25   00:28 410662K  a5 Be4 Kf6 Kf4 Rd4 Ke3 Rxc4 Bc6 Rc2 g4 Rh2 h4 Rxh4 Bb5 Rh3 Ke4 Rg3 Kf4 Rg2 Ke3 Rg1 Kf4 Rd1 Ke3 Rb1 f4 Kg7 Ke4 Rb4+ Ke3 c4 f5 c3 Kd3 Rxg4 Kxc3 Kf6 Bc6 Rf4 Bd7 Ke7 Bc6 Kd6 
36   +3.44   00:39 567697K  a5 Be4 Kf6 Kf4 Rd4 Ke3 Rxc4 Bc6 Rc3+ Kd2 Ra3 g3 Ra2+ Ke3 Rg2 g4 Rh2 Bb5 Rxh3 Ke4 Rg3 Kf4 Rg2 Ke3 Rg1 Kf4 Rd1 Ke3 Rd4 f4 Rb4 Bd7 Kf7 Bb5 Ke7 g5 Kf7 Bd7 Rd4 Bc6 Ke7 g6 Kf6 f5 Rg4 
Nodes: 567723592
Nodes/second: 14395344
Best move: a5
Ponder move: Be4

[tpoppins]

The established convention in chess literature is to prefix Black's moves with an ellipsis in cases where White's preceding move is not listed. Thus the title of this thread should read "The ...a5 atom smasher". Just in case a human happens to read this thread.

BTW, here's a thread on ECF about Liren's remarkable unbeaten run: Ding Liren/Liren Ding... (with a gratuitous ellipsis ;)

[Dann Corbit]

The established convention in chess literature is to prefix Black's moves with an ellipsis in cases where White's preceding move is not listed. Thus the title of this thread should read "The ...a5 atom smasher". Just in case a human happens to read this thread.

BTW, here's a thread on ECF about Liren's remarkable unbeaten run: Ding Liren/Liren Ding... (with a gratuitous ellipsis

I am used to EPD which does not need it, so I will probably make this faux pas again and again.

[tpoppins]

You know you've been reading the Matrix undecoded for too long when you don't see the symbols anymore, it's all just blondes, redheads and brunettes.
You know you've been reading engine output without using a GUI for too long when tournament directors complain about your scoresheets being in coordinate notation.
You know you've been tinkering with engines for too long when you fix a bug in a long-forgotten engine without having the slightest recollection of having done a build for the original buggy version 15+ years prior.
If your name has one "n" too many you just know.

[Dann Corbit]

If your name has one "n" too many you just know.

That happened by accident.

When I was born (in a house, Spirit Lake Idaho was too small for a hospital), they asked my mother what she wanted my name to be. She said,
"D - A - N - N" to the doctor because she was thinking of "Danny".
But then she remembered she wanted it to be "Daniel" so she continued,
"I - E - L"

So my legal name is Danniel. Hence, I shorten it to Dann just to be weird.

[tpoppins]

Interesting! Earlier this year I met a guy who runs a local bike store in his spare time and had to do a double-take at his business card. "Briann". I remembered you at once and asked him if it was a misprint. He laughed and said he gets questions like this all the time. Turned out it was his Mom's doing as well; he dismissed the subject with the brief "she was a hippie" without going into details.

I bet you'd grown to view it as unique rather than weird a long time ago. A name like that may occasion some extra teasing from aspiring wiseasses at school but as you grow up you come to appreciate signing with a name shared by so few. Yes, speaking from own experience here.

BTW, you don't seem to have picked on the 15+-year-old engine hint. You have been tinkering with engines for too long!