Author: Eelco de Groot
Date: 14:52:44 09/15/05
Go up one level in this thread
On September 15, 2005 at 17:03:28, Andreas Guettinger wrote:
>On September 15, 2005 at 14:25:17, Ed Schröder wrote:
>
>>On September 15, 2005 at 14:07:05, Robert Hyatt wrote:
>>
>>>On September 15, 2005 at 07:21:19, Ed Schröder wrote:
>>>
>>>>On September 15, 2005 at 06:43:22, Gian-Carlo Pascutto wrote:
>>>>
>>>>>On September 15, 2005 at 06:26:30, Ed Schröder wrote:
>>>>>
>>>>>>On September 15, 2005 at 04:30:38, Mark Young wrote:
>>>>>>
>>>>>>>On September 14, 2005 at 17:05:59, Ernst Walet wrote:
>>>>>>>
>>>>>>>>Because Zappa 1.1 is SMP and 64 bit, I gave it a try and was pleasant suprised.
>>>>>>>>One of my favourite chess positions is this one, where Kasparov played Rxd4.
>>>>>>>>How do other engines do? If your engine finds it please give it a couple of more
>>>>>>>>plies to see if it holds it.
>>>>>>>
>>>>>>>The better test for the engine in this position, is to see when the program see
>>>>>>>that Rxd4 is not winning. Since Rxd4 is only a draw with best play.
>>>>>>>This is why many programs will not play Rxd4, or drop the move with a longer
>>>>>>>search.
>>>>>>
>>>>>>1. Rxd4 cxd4 2. Re7+ Kb6 3. Qxd4+ Kxa5 4. b4+ Ka4 5. Ra7 Bb7 6. Rxb7 Qxd5 7. Rb6
>>>>>>1-0
>>>>>
>>>>>I always thought that simply 1. .. Kb6 was never refuted?
>>>>
>>>>You are absolutely right, missed that one. But I would like to see the engine
>>>>that plays 1..Kb6
>>>>
>>>>Hmmm...
>>>>
>>>>Ed
>>>
>>>
>>>Here is one: (this on my dual xeon, searching around 2M nodes per second. WCCC
>>> opteron would be 8x faster...
>>>
>>> 12 13.94 -1.77 1. ... cxd4 2. Re7+ Kb6 3. Qxd4+ Kxa5
>>> 4. Qc3+ b4 5. axb4+ Qxb4 6. Qc7+ Ka4
>>> 7. b3+ Ka3 8. Qe5 Qb6 9. Qb2+ Kb4 10.
>>> c3+ Kc5 11. Qf2+ Kd6 12. Qxb6+ Kxe7
>>> 13. c4
>>> 12-> 20.05 -1.77 1. ... cxd4 2. Re7+ Kb6 3. Qxd4+ Kxa5
>>> 4. Qc3+ b4 5. axb4+ Qxb4 6. Qc7+ Ka4
>>> 7. b3+ Ka3 8. Qe5 Qb6 9. Qb2+ Kb4 10.
>>> c3+ Kc5 11. Qf2+ Kd6 12. Qxb6+ Kxe7
>>> 13. c4 (s=2)
>>> 13 26.64 +1 1. ... cxd4
>>> 13 34.01 -0.01 1. ... cxd4 2. Re7+ Kb6 3. Qxd4+ Kxa5
>>> 4. b4+ Ka4 5. Qc3 Qxd5 6. Qc7 Qd1+
>>> 7. Kb2 Qd4+ 8. Kb1 Qd1+
>>> 13 2:46 -0.31 1. ... Kb6 2. Nb3 Bxd5 3. Qxd6+ Rxd6
>>> 4. Rd2 Rhd8 5. Red1 Ne8 6. f4 Bf3 7.
>>> Rxd6+ Nxd6 8. Rd3 Be4 9. Rd2 a5
>>>
>>>Plays Kb6 to avoid a perceived repetition after cxd4...
>>
>>Yep mine plays it too. New Challenge, which engine finds 5.Ra7!!
>>
>>This after: 1. Rxd4 cxd4 2. Re7+ Kb6 3. Qxd4+ Kxa5 4. b4+ Ka4 5. Ra7 Bb7 6. Rxb7
>>Qxd5 7. Rb6
>>
>>Ed
>
>Probably none. Is there a win after
>
>.... 7.Rb6 a5 8.Qe3 Rc8 9.Bxc8 Rxc8 10.Rxf6 Rxc2 11.Kxc2 Qa2+ 12.Kd3 Qc4+ 13.Kd2
>Qa2+ 14.Ke1 Qa1+ 15.Kf2 Qxf6
>
>?
>regards
>Andy
I think it will prove a very hard combination for most programs, even though
Vincent Lejeune had a good result here with a chessengine which he doesn't name?
Already finding that 6..Qxd5 isn't equalizing for Black is a difficult
challenge. I tried a few random chessengines and personalities just to see what
they find with a short searchdepth:
1.e4 d6 2.d4 Nf6 3.Nc3 g6 4.Be3 Bg7 5.Qd2 c6 6.f3 b5 7.Nge2 Nbd7 8.Bh6
Bxh6 9.Qxh6 Bb7 10.a3 e5 11.O-O-O Qe7 12.Kb1 a6 13.Nc1 O-O-O 14.Nb3
exd4 15.Rxd4 c5 16.Rd1 Nb6 17.g3 Kb8 18.Na5 Ba8 19.Bh3 d5 20.Qf4 Ka7
21.Rhe1 d4 22.Nd5 Nbxd5 23.exd5 Qd6 24.Rxd4 cxd4 25.Re7 Kb6 26.Qxd4
Kxa5 27.b4 Ka4 28.Ra7 Bb7 29.Rxb7
[D]3r3r/1R3p1p/p2q1np1/1p1P4/kP1Q4/P4PPB/2P4P/1K6 b - -
Pro Deo 1.1 Default
00:00:28 13.00 0.42 29..Qxd5 30.Qxf6 Rd6 31.Qc3 Qc4 32.Qe3 Rd1
33.Kb2 Qd4 34.Qxd4 Rxd4 35.Rxf7 Rd1 36.Be6
Rf1 37.Bb3
00:01:21 14.00 -0.54 29..Qxd5 30.Rb6 a5 31.Qe3 Rc8
Pro Deo 1.1 Vulcan {9k16h5}
00:00:46 14.00 0.00 29..Qxd5 30.Rb6 a5 31.Qe3 Rc8 32.Bxc8 Rxc8
33.Rxf6 Rxc2 34.Kxc2
00:02:09 15.00 -3.05 29..Qxd5 30.Rb6 a5 31.Ra6 Ra8 32.Qe3 Rxa6
33.Kb2 axb4
Pro Deo 1.1 Vulcan {9k16hj}
00:01:17 14.00 0.41 29..Qxd5 30.Qc3 Qc4 31.Qxf6 Rd1 32.Kb2 Ra8
33.Qb6 Qd4 34.Qxd4 Rxd4 35.Rxf7 Rd6 36.Rxh7
Rad8
00:03:39 15.00 -0.47 29..Qxd5 30.Rb6 a5 31.Qe3 Qd1 32.Kb2 Rd3 33.Qxd3
Qxd3 34.cxd3 Nd5 35.Rd6
Gandalf 6.01
00:02:04.3 0,00 15 80611156 Qxd5 Qc3 Qc4 Qxf6 Rd1+ Kb2 Ra8 Qb6 Qd4+ Qxd4 Rxd4
Rxf7 Rd6 Rxh7 Re8 Rd7 Rxd7 Bxd7 Re3 f4 Rxa3
00:03:59.6 -0,03 16 152679971 Qxd5 Qc3 Qc4 Qxf6 Rd1+ Kb2 Ra8 Qb6 Qd4+ Qxd4 Rxd4
Rxf7 Rd6 Rxh7 Re8 f4 Re2 Bg4 Re3 Ra7 Rxa3
00:08:36.2 -0,03 17 322507677 Qxd5 Qc3 Qc4 Qxf6 Rd1+ Kb2 Ra8 Qb6 Qd4+ Qxd4 Rxd4
Rxf7 Rd6 Rxh7 Re8 f4 Re2 Bg4 Re3 Ra7 Rxa3
Fruit 2.1
00:00:04.1 0,00 11 4100481 Qxd5 Qxf6 Qxb7 Qc3 Qd5 Qc7 Qd1+ Ka2 Qd5+ Kb1
00:00:10.3 -0,25 12 10748647 Qxd5 Qc3 Qc4 Qxf6 Rd1+ Kb2 Ra8 Qb6 Qd4+ Qxd4 Rxd4
Rxf7 a5 bxa5 Kxa5 Rxh7 Re8
00:00:18.4 -0,31 13 19493843 Qxd5 Qc3 Qc4 Qxf6 Rd1+ Kb2 Ra8 Qb6 Qd4+ Qxd4 Rxd4
Rxf7 a5 bxa5 Rd2 Be6 Rxh2
00:00:31.9 -0,56 14 34272847 Qxd5 Qc3 Qc4 Qxf6 Rd1+ Kb2 Ra8 Qb6 Qd4+ Qxd4 Rxd4
Rxf7 a5 Be6 axb4 Bb3+ Ka5 axb4+ Kb6 Kc3 Rd1 Rxh7
00:01:03.5 -0,56 15 68258223 Qxd5 Qc3 Qc4 Qxf6 Rd1+ Kb2 Ra8 Qb6 Qd4+ Qxd4 Rxd4
Rxf7 a5 Be6 axb4 Bb3+ Ka5 axb4+ Kb6 Kc3 Rd1 Rxh7
00:02:34.2 -0,46 16 164746410 Qxd5 Qc3 Qc4 Qxf6 Rd1+ Kb2 Ra8 Qb6 Qd4+ Qxd4 Rxd4
Rxf7 a5 Be6 axb4 Bb3+ Ka5 axb4+ Kb6 Rxh7 Rd2 Be6 Kc6
Spike 1.0
00:00:19.6 0,00 12 17899082 Qxd5 Qxf6 Qxb7 Qc3 Qd5 Qc7 Qd1+ Ka2 Qd5+ Kb1
00:00:27.8 -0,30 13 25754347 Qxd5 Qxf6 Qxb7 Qc3 Qd5 Qc7 Qd1+ Ka2 Qd5+ Kb1
00:00:35.0 -0,30 13 32976203 Qxd5 Qxf6 Qxb7 Qc3 Qd5 Qc7 Qd1+ Ka2 Qd5+ Kb1
00:00:47.7 -1,55 13 45302934 Qxd5 Rb6 a5 Ra6 Ra8 Qe3 Rxa6 Kb2 axb4 axb4 Qa2+
Kxa2 Kxb4+ Kb2 Ka5 Qa3+ Kb6 Qd6+ Ka7 Qc7+ Ka8 Qxf7
00:01:04.4 -1,55 13 61419679 Qxd5 Rb6 a5 Ra6 Ra8 Qe3 Rxa6 Kb2 axb4 axb4 Qa2+
Kxa2 Kxb4+ Kb2 Ka5 Qa3+ Kb6 Qd6+ Ka7 Qc7+ Ka8 Qxf7
00:01:13.4 -1,85 14 70128264 Qxd5 Rb6 a5 Ra6 Ra8 Qe3 Rxa6 Kb2 axb4 axb4 Qa2+
Kxa2 Kxb4+ Kb2 Ka5 Qa3+ Kb6 Qd6+ Ka7 Qc7+ Ka8 Qxf7
00:01:52.8 -1,85 14 107982158 Qxd5 Rb6 a5 Ra6 Ra8 Qe3 Rxa6 Kb2 axb4 axb4 Qa2+
Kxa2 Kxb4+ Kb2 Ka5 Qa3+ Kb6 Qd6+ Ka7 Qc7+ Ka8 Qxf7
00:02:00.4 -1,55 14 115768886 Qxd5 Rb6 a5 Ra6 Ra8 Qe3 Rxa6 Kb2 axb4 axb4 Qa2+
Kxa2 Kxb4+ Kb2 Ka5 Qa3+ Kb6 Qd6+ Ka7 Qc7+ Ka8 Qxf7
00:02:00.4 -1,55 14 115768921 Qxd5 Rb6 a5 Ra6 Ra8 Qe3 Rxa6 Kb2 axb4 axb4 Qa2+
Kxa2 Kxb4+ Kb2 Ka5 Qa3+ Kb6 Qd6+ Ka7 Qc7+ Ka8 Qxf7
00:02:15.9 -1,85 15 131135852 Qxd5 Rb6 a5 Ra6 Ra8 Qe3 Rxa6 Kb2 axb4 axb4 Qa2+
Kxa2 Kxb4+ Kb2 Ka5 Qa3+ Kb6 Qd6+ Ka7 Qc7+ Ka8 Qxf7
00:02:54.2 -1,85 15 167899182 Qxd5 Rb6 a5 Ra6 Ra8 Qe3 Rxa6 Kb2 axb4 axb4 Qa2+
Kxa2 Kxb4+ Kb2 Ka5 Qa3+ Kb6 Qd6+ Ka7 Qc7+ Ka8 Qxf7
00:03:17.0 -1,89 15 190978182 Qxd5 Rb6 a5 Ra6 Ra8 Qe3 Rxa6 Kb2 axb4 axb4 Qa2+
Kxa2 Kxb4+ Kb2 Rc6 Qa3+ Kc4 Bf1+ Kd5 Qd3+ Kc5 Qxb5+ Kd6
00:03:28.7 -1,89 15 201557736 Qxd5 Rb6 a5 Ra6 Ra8 Qe3 Rxa6 Kb2 axb4 axb4 Qa2+
Kxa2 Kxb4+ Kb2 Rc6 Qa3+ Kc4 Bf1+ Kd5 Qd3+ Kc5 Qxb5+ Kd6
00:04:11.2 -2,19 16 242567591 Qxd5 Rb6 a5 Ra6 Ra8 Qe3 Rxa6 Kb2 axb4 axb4 Qa2+
Kxa2 Kxb4+ Kb2 Rc6 Qa3+ Kc4 Bf1+ Kd5 Qd3+ Kc5 Qxb5+ Kd6
(Not bad from Spike!)
Eelco
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