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Subject: Re: A crafty try with a crafty question

Author: blass uri

Date: 01:16:50 06/07/00

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On June 06, 2000 at 15:10:07, pete wrote:

>On June 05, 2000 at 19:18:56, Pete R. wrote:
>
>>Here is the diagram Mr. Uri posted last week:
>>
>>[D]r2qr3/pb3pk1/np3b1N/2pp3Q/3P4/1PR1P1P1/P4PBP/5RK1 w - - 0 1
>>
>>I let Fritz 5.32 run the weekend on it, and after a great deal of
>>thought it decided the best move is...1. e4!!.
>>
>>Analysis by Fritz 5.32:
>>
>>-+  (-2.94) 1.dxc5 Bxc3 2.Nxf7   00:00:00
>>=  (-0.25) 1.Nxf7   00:00:00
>>²  (0.31) 1.Nxf7   00:00:00
>>=  (0.25) 1.Nxf7 Qe7   00:00:00
>>³  (-0.47) 1.Nxf7 Qe7 2.Ne5   00:00:00
>>³  (-0.44) 1.Rfc1   00:00:00
>>³  (-0.41) 1.Rfc1 Qd7 2.Nf5+ Kg8   00:00:00
>>³  (-0.37) 1.Rd3   00:00:00
>>³  (-0.34) 1.Rd3 Qd7 2.dxc5 Nxc5 3.Nf5+ Kg8   00:00:00
>>³  (-0.31) 1.Qxf7+   00:00:00
>>²  (0.50) 1.Qxf7+ Kxh6 2.Qxb7 Nb4   00:00:00
>>=  (0.06) 1.Qxf7+ Kxh6 2.Qxb7 Nb4 3.a3   00:00:00
>>=  (0.09) 1.Nxf7   00:00:00
>>²  (0.44) 1.Nxf7 Qd7 2.Ne5 Bxe5   00:00:00
>>²  (0.53) 1.Nxf7 Qe7 2.Nh6 Rh8 3.Nf5+ Kf8   00:00:00
>>²  (0.56) 1.Nxf7 Qd7 2.Nh6 Kf8 3.Nf5 Rac8   00:00:00
>>²  (0.47) 1.Nxf7 Qe7 2.Nh6 Bc8 3.Qxd5 Nc7 4.Nf5+ Bxf5 5.Qxf5 cxd4   00:00:00
>>²  (0.69) 1.Nxf7 Qc7 2.Nh6 Rf8 3.Nf5+ Kg8 4.f4 Rae8 5.Nh6+ Kg7   00:00:03
>>±  (0.75) 1.Nxf7 Qc7 2.Nh6 Rh8 3.Nf5+ Kf8 4.Qg6 Bg7 5.Rd1 Rd8   00:00:08
>>²  (0.69) 1.Nxf7 Qc7 2.Nh6 Rad8 3.Nf5+ Kf8 4.a3 Qf7 5.Qxf7+ Kxf7   00:00:24
>>±  (0.81) 1.Nxf7 Qc7 2.Nh6 Rh8 3.Nf5+ Kf8 4.Qg6 Bg7 5.Bxd5 Bxd5   00:01:27
>>±  (0.81) 1.Nxf7 Qc7 2.Nh6 Rf8 3.g4 Kh8 4.Nf7+ Kg8 5.Qg6+ Bg7   00:03:49
>>±  (0.84) 1.g4   00:28:08
>>±  (1.06) 1.g4 Rh8 2.Qxf7+ Kxh6 3.f4 Rg8 4.g5+ Bxg5 5.Qxb7 Nc7   01:22:25
>>±  (1.00) 1.g4 Rh8 2.Qxf7+ Kxh6 3.f4 Rg8 4.Qxb7 Nc7 5.h3 Bg7   01:41:17
>>²  (0.50) 1.g4 Rh8 2.Qxf7+ Kxh6 3.f4 Rg8 4.Qxb7 Nb4 5.g5+ Bxg5   04:56:05
>>²  (0.53) 1.Nxf7   05:04:04
>>²  (0.69) 1.Nxf7 Qd7 2.Ne5 Bxe5 3.dxe5 Qe6 4.f4 Rh8 5.Qg5+ Kf7   09:27:46
>>±  (0.72) 1.e4   16:27:07
>>±  (0.78) 1.e4 dxe4 2.g4 Rh8   22:38:47
>>±  (0.84) 1.e4 dxe4 2.g4 Rh8 3.Qxf7+ Kxh6 4.Qxb7 Nc7 5.Rh3+ Kg7   37:03:44
>>
>>Final depth reached is 16 ply.  As you can see it took 16.5 hours on a PII
>>400 to decide on 1.e4!!.  According to my analysis (although not completely
>>exhaustive) I do think this is the best move and white likely wins in all
>>lines:
>>
>>1. e4!! dxe4 2. g4 Rh8
>>
>>other tries:
>>
>>  A) 2...Bc8 3. Qxf7+ Kxh6 4. Rh3+ Bh4 5. Qh5+ Kg7 6. Rxh4 Qf6
>>     7. Qxe8 Qxh4 8. Re1 +-.
>>
>>  B) 2...Bh4 3. Nf5+ Kg8 4. g5 Qd7 5. g6 fxg6 6. Qxg6+ Kf8 7. Rg3 +-.
>>
>>  C) 2...Bg5 3. Nf5+ Kf6 4. f4 exf3 5. h4 Bd2 6. Bxf3 Rh8 7. g5+ Ke6
>>     8. Re1+ Bxe1 9. Re3+ +-.
>>
>>3. Qxf7+ Kxh6 4. Rh3+ Bh4 5. Qxb7 and white wins:
>>
>>       a) 5...Nc7 6. dxc5 bxc5 (...Kg7 7. cxb6 axb6 8. Rc3 Rc8
>>            9. Rfc1 Bxf2+ 10. Kxf2 +-) 7. Rxh4+ Qxh4 8. Qc6+ Kg7
>>          9. Qxc7+ Kg8 10. h3 +-.
>>
>>       b) 5...cxd4 6. f4 Nc7 7. Qxe4 Kg7 8. Qe5+ Bf6 9. Rxh8 Kxh8
>>          10. Qh5+ Kg8 11. Qg6+ Kf8 12. g5 +-.
>>
>>       c) 5...Qg5 6. Qxa6 Qxg4 (...Rag8 7. f3 cxd4 8. Qc4 e3 9. Rc1 Rg6
>>            10. Qxd4 Rd8 11. Qe4 +-) 7. f3 exf3 8. Rfxf3 Rae8 9. Qf1 +-.
>>
>>So black is dead meat after 1...dxe4. Black's only serious alternative is
>>
>>1....Rh8, leading to the line 1. e4 Rh8 2. Qxf7+ Kxh6 3. Rf3 Rf8
>>4. Qxb7 and now Nb4 appears best for black.  I've analyzed a number of
>>continuations and have not been able to prove an ironclad win for white
>>in all of them, but white definitely has the upper hand and black is
>>merely defending.
>
>I think your analysis is quite convincing ; e4 seems to be the best move and
>requires a very deep search . Here some output from Crafty17.10 :
>
>12    15:51   0.06   1. g4 Qd7 2. g5 Bd8 3. Bh3 Qc7 4. Nf5+
>                                    Kg8 5. Qh6 f6 6. gxf6 Re6 7. Ne7+ Rxe7
>                                    8. Qg6+ Rg7 9. fxg7 Qxg7 10. Qxg7+
>                                    Kxg7 11. dxc5 bxc5
>               12->  19:05   0.06   1. g4 Qd7 2. g5 Bd8 3. Bh3 Qc7 4. Nf5+
>                                    Kg8 5. Qh6 f6 6. gxf6 Re6 7. Ne7+ Rxe7
>                                    8. Qg6+ Rg7 9. fxg7 Qxg7 10. Qxg7+
>                                    Kxg7 11. dxc5 bxc5
>               13    37:59     --   1. g4
>               13    42:36  -0.48   1. g4 Rh8 2. Qxf7+ Kxh6 3. Qxb7 Nb4
>                                    4. f4 Rg8 5. g5+ Bxg5 6. fxg5+ Qxg5
>                                    7. Rf2 Raf8 8. e4 Qg4 9. Rg3 Qd1+ 10.
>                                    Rf1 Rxf1+ 11. Bxf1 Rxg3+ 12. hxg3 Qxd4+
>               13    72:19  -0.22   1. e4 dxe4 2. g4 Bc8 3. Qxf7+ Kxh6
>                                    4. Rh3+ Bh4 5. Rxh4+ Qxh4 6. Qxe8 Kg7
>                                    7. Qe5+ Kf8 8. Qf4+ Kg8 9. Bxe4 Rb8
>               13   111:18   0.00   1. Nxf7 Qd7 2. Nh6 Kf8 3. Qf3 Ke7 4.
>                                    Qf4 Qc7 5. Qf5 Qd7 6. Qf4
>         (4)   13-> 137:08   0.00   1. Nxf7 Qd7 2. Nh6 Kf8 3. Qf3 Ke7 4.
>                                    Qf4 Qc7 5. Qf5 Qd7 6. Qf4
>         (3)   14   141:49  -0.03   1. Nxf7 Qd7 2. Nh6 Kf8 3. Ng4 Bg7 4.
>                                    Nh6 Rab8 5. h3 cxd4 6. exd4 Bf6 7.
>                                    Nf5 Rbc8 8. Rfc1
>         (2)   14   264:24   0.30   1. e4 dxe4 2. g4 Bc8 3. Qxf7+ Kxh6
>                                    4. Rh3+ Bh4 5. Qh5+ Kg7 6. Rxh4 Rb8
>                                    7. Bxe4 Qxh4 8. Qxh4 Rxe4 9. Qg5+ Kh7
>                                    10. Qh5+ Kg7
>
>
>I didn't want to wait longer and stopped here but I'd expect a fail high on e4
>at ply 15 .
>
>What is strange to me is that Dr Hyatt has posted that Crafty17.11 sticks to
>Nxf7 right from the start until end of ply 14 . This is really a major change to
>17.10 and the result seems to be not too good .

I do not know if this is a major change.
The question is if parallel crafty 17.10 get the same results.

I am also not sure if e4 is the best move and it is possible that Nxf7 is the
best move.

Uri



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