Author: Tim Foden
Date: 01:33:04 03/05/02
Go up one level in this thread
On March 04, 2002 at 22:55:30, Dann Corbit wrote:
>On March 04, 2002 at 17:43:29, Albert Silver wrote:
>
>>The following position occurred in Spassky-Beliavsky, Reykjavik, 1988
>>
>>[D]2b1qrk1/5p1p/pBn3p1/1p2p3/4P2N/bBP1Q3/P4PPP/3R2K1 w - -
>>
>>Spassky found a tremendous move 25.Nxg6!! and won the game. I don't think any
>>engines will have much luck with it but feel free to try it. I've analyzed it in
>>detail and can verify that it is the strongest move and correct, so as a further
>>challenge, see if you can find the *strongest* continuation after the possible
>>defense: 25...hxg6 26.Qh6 Be6!?
>
>The new GLC says this:
>>epd 999 \nxg6.epd
> Line 001: Test [Nxg6]...
> Generating internal KP-K end-game table...
> Done (0.311 secs)
> Game stage: Middle game
> Current eval: 0.276
> Ply Time Score Nodes Principal Variation
> 4 0.02 +0.053 5730 Bd5 Ne7 2. Bb3 Bb7
> 4 0.03 +0.053 13473 Bd5 Ne7 2. Bb3 Bb7
> 5 0.05 +0.051 21854 Bd5 Bg4 2. Nf3 Qd7 3. c4
> 5 0.11 +0.121 64153 c4 Qe7 2. cxb5 axb5 3. Qh6 Bb7
> 5 0.13 +0.121 74296 c4 Qe7 2. cxb5 axb5 3. Qh6 Bb7
> 6 0.15 +0.070 91419 c4 Qe7 2. cxb5 axb5 3. Qh6 Be6 4. Bxe6 Qxe6
> 6 0.27 +0.070 171617 c4 Qe7 2. cxb5 axb5 3. Qh6 Be6 4. Bxe6 Qxe6
> 7 0.36 +0.046 238211 c4 Qe7 2. cxb5 axb5 3. Qh6 Be6 4. Bxe6 Qxe6 5. Rd2
> 7 0.72 +0.221 449451 Bd5 Bb7 2. Nf3 Qe7 3. Ng5 Bd6 4. f3
> 7 0.83 +0.221 529585 Bd5 Bb7 2. Nf3 Qe7 3. Ng5 Bd6 4. f3
> 8 1.73 +0.089 1046198 Bd5 Ne7 2. c4 b4 3. Ba8 Qa4 4. Rd6 Be6
> 8 2.26 +0.342 1393452 c4 Qe7 2. cxb5 axb5 3. Nf3 Bg4 4. Rd5 b4 5. Ng5
> 8 2.51 +0.342 1570209 c4 Qe7 2. cxb5 axb5 3. Nf3 Bg4 4. Rd5 b4 5. Ng5
> 9 4.41 +0.324 2789434 c4 Bb4 2. cxb5 axb5 3. Nf3 Be6 4. a3 Bxb3 5. Qxb3
> Be7 6. Qe3
> 9 5.98 +0.324 3858858 c4 Bb4 2. cxb5 axb5 3. Nf3 Be6 4. a3 Bxb3 5. Qxb3
> Be7 6. Qe3
> 10 10.31 +0.413 6654866 c4 Qe7 2. Nf3 Bb7 3. cxb5 axb5 {ht}
> 10 12.04 +0.413 7904690 c4 Qe7 2. Nf3 Bb7 3. cxb5 axb5 {ht}
> 11 29.56 +0.321 19057k c4 Bg4 2. f3 Bc8 3. cxb5 axb5 4. Bxf7+ Rxf7 5. Qxa3
> g5 6. Nf5 Bxf5 7. exf5 Rxf5
> 11 51.66 +0.367 33187k Nf3 Bg4 2. Bd5 Qd7 3. h3 Bxf3 4. Qxf3 Bb2 5. Rb1
> Ba3 6. c4 Bb4 7. cxb5 axb5
> 11 55.95 +0.367 35932k Nf3 Bg4 2. Bd5 Qd7 3. h3 Bxf3 4. Qxf3 Bb2 5. Rb1
> Ba3 6. c4 Bb4 7. cxb5 axb5
> 12 1:31 +0.461 57301k Nf3 Bg4 2. Bd5 Qd7 3. c4 Bd6 4. h3 Bxf3 5. Qxf3
> bxc4 6. Bxc4 Qb7 7. Qe3 Rb8
> 12 2:26 +0.461 93675k Nf3 Bg4 2. Bd5 Qd7 3. c4 Bd6 4. h3 Bxf3 5. Qxf3
> bxc4 6. Bxc4 Qb7 7. Qe3 Rb8
> 13 5:23 +0.617 200462k Nf3 Bg4 2. c4 Be7 3. cxb5 axb5 4. h3 Bxf3 5. Qxf3
> Qb8 6. Qe3 Qb7 7. Bd5 Rc8 8. f3
> 13 7:50 +0.617 298258k Nf3 Bg4 2. c4 Be7 3. cxb5 axb5 4. h3 Bxf3 5. Qxf3
> Qb8 6. Qe3 Qb7 7. Bd5 Rc8 8. f3
> 14 11:52 +0.534 446732k Nf3 Bg4 2. c4 Be7 3. cxb5 axb5 4. h3 Bxf3 5. Qxf3
> Qb8 6. Qe3 Bg5 7. Qxg5 Qxb6 8. Rd7 Qc5
> local: t=16:39 nps=638782.3 n=638153773 (18.0% / 82.0%) fh=89.1%
> total: t=16:39 nps=638782.3 n=638153773 draws=416196
> trans: probes=114468411 hits=14489233 (12.66%) draft=9787234 (8.55%)
> tcuts: exact=1219 (0.00%) upper=6641525 (5.80%) lower=2411588 (2.11%)
> tstor: exact=1748 (0.00%) upper=43586187 (72.25%) lower=16741263 (27.75%)
> ext: check=37626828 recap=1761032 ppush=80439 1rep=2657617 thrt=0
> q-moves: gen=440786013 tested=217181268 made/un=86757959 max-dep=14
> max eval diff: part-1=3.296 part-2=2.346
> !m Nh4-f3 534 5166 Bd5 >
>move h4f36 3/48 Bd5 >
> time left 10.00
> -> Score=534 PV=Nf3 Bg4 2. c4 Be7 3. cxb5 axb5 4. h3 Bxf3 5. Qxf3 Qb8 6. Qe3
>Bg5 7. Qxg5 Qxb6 8. Rd7 Qc5
> Game finished test: 0
>>
> --------------------------------------------
> 2b1qrk1/5p1p/pBn3p1/1p2p3/4P2N/bBP1Q3/P4PPP/3R2K1 w - - bm Nxg6;
> Line 001: Test [Nxg6]: failed [Nf3; score=0.534]
>
> Passed 0 out of 1 (0 invalid)
Hi Dann...
With some more hash (I'm guessing you just used the default 6MB), and a faster
processor, GLC manages to find Nxg6 in less than your 999 seconds :)
900MHz?, 6MB: not found in 999 seconds (638153773 nodes),
1.47GHz, 48MB: found after 16:28 (912270000 nodes),
1.47Ghz, 96MB: found after 13:34 (740192000 nodes).
Analysis follows.
48MB Hash, Athlon XP 1.47GHz:
Game stage: Middle game
Current eval: 0.276
Ply Time Score Nodes Principal Variation
4 0.04 +0.053 5730 Bd5 Ne7 2. Bb3 Bb7
4 0.06 +0.053 13473 Bd5 Ne7 2. Bb3 Bb7
5 0.07 +0.051 21854 Bd5 Bg4 2. Nf3 Qd7 3. c4
5 0.11 +0.121 64153 c4 Qe7 2. cxb5 axb5 3. Qh6 Bb7
5 0.13 +0.121 74296 c4 Qe7 2. cxb5 axb5 3. Qh6 Bb7
6 0.15 +0.070 91419 c4 Qe7 2. cxb5 axb5 3. Qh6 Be6 4. Bxe6 Qxe6
6 0.23 +0.070 171617 c4 Qe7 2. cxb5 axb5 3. Qh6 Be6 4. Bxe6 Qxe6
7 0.30 +0.046 238211 c4 Qe7 2. cxb5 axb5 3. Qh6 Be6 4. Bxe6 Qxe6 5. Rd2
7 0.54 +0.221 449463 Bd5 Bb7 2. Nf3 Qe7 3. Ng5 Bd6 4. f3
7 0.62 +0.221 529549 Bd5 Bb7 2. Nf3 Qe7 3. Ng5 Bd6 4. f3
8 1.23 +0.089 1045224 Bd5 Ne7 2. c4 b4 3. Ba8 Qa4 4. Rd6 Be6
8 1.59 +0.342 1392147 c4 Qe7 2. cxb5 axb5 3. Nf3 Bg4 4. Rd5 b4 5. Ng5
8 1.76 +0.342 1568627 c4 Qe7 2. cxb5 axb5 3. Nf3 Bg4 4. Rd5 b4 5. Ng5
9 3.04 +0.324 2786465 c4 Bb4 2. cxb5 axb5 3. Nf3 Be6 4. a3 Bxb3 5. Qxb3
Be7 6. Qe3
9 4.08 +0.324 3853981 c4 Bb4 2. cxb5 axb5 3. Nf3 Be6 4. a3 Bxb3 5. Qxb3
Be7 6. Qe3
10 6.94 +0.413 6619849 c4 Qe7 2. Nf3 Bb7 3. cxb5 axb5 {ht}
10 8.11 +0.413 7855251 c4 Qe7 2. Nf3 Bb7 3. cxb5 axb5 {ht}
11 19.66 +0.321 18402k c4 Bg4 2. f3 Bc8 3. cxb5 axb5 4. Bxf7+ Rxf7 5. Qxa3
g5 6. Nf5 Bxf5 7. exf5 Rxf5
11 33.37 +0.367 31103k Nf3 Bg4 2. Bd5 Qd7 3. h3 Bxf3 4. Qxf3 Bb2 5. Rb1
Ba3 6. c4 Bb4 7. cxb5 axb5
11 35.90 +0.367 33419k Nf3 Bg4 2. Bd5 Qd7 3. h3 Bxf3 4. Qxf3 Bb2 5. Rb1
Ba3 6. c4 Bb4 7. cxb5 axb5
12 59.01 +0.461 54054k Nf3 Bg4 2. Bd5 Qd7 3. c4 Bd6 4. h3 Bxf3 5. Qxf3
bxc4 6. Bxc4 Qb7 7. Qe3 Rb8
12 1:23 +0.461 77813k Nf3 Bg4 2. Bd5 Qd7 3. c4 Bd6 4. h3 Bxf3 5. Qxf3
bxc4 6. Bxc4 Qb7 7. Qe3 Rb8
13 2:29 +0.572 135881k Nf3 Bg4 2. Bd5 Qd7 3. c4 Bd6 4. h3 Bxf3 5. Qxf3 Qb7
6. cxb5 axb5 7. Qe3 Rc8 8. f3
13 4:13 +0.572 236743k Nf3 Bg4 2. Bd5 Qd7 3. c4 Bd6 4. h3 Bxf3 5. Qxf3 Qb7
6. cxb5 axb5 7. Qe3 Rc8 8. f3
14 7:47 +0.534 427941k Nf3 Bg4 2. c4 Be7 3. cxb5 axb5 4. h3 Bxf3 5. Qxf3
Qb8 6. Qe3 Bg5 7. Qxg5 Qxb6 8. Rd7 Qc5
14 16:28 +0.544 912270k Nxg6 hxg6 2. Qh6 Be6 3. Rd3 Ne7 4. Bxe6 fxe6 5. c4
Bb4 6. Rh3 Kf7 7. Qh7+ Kf6 8. Rf3+ Nf5 9. exf5
exf5 10. cxb5 Qxb5
14 17:13 +0.544 956923k Nxg6 hxg6 2. Qh6 Be6 3. Rd3 Ne7 4. Bxe6 fxe6 5. c4
Bb4 6. Rh3 Kf7 7. Qh7+ Kf6 8. Rf3+ Nf5 9. exf5
exf5 10. cxb5 Qxb5
15 18:11 +0.808 1013m Nxg6 hxg6 2. Qh6 Be6 3. Rd3 Ne7 4. Bxe6 fxe6 5. Rh3
Kf7 6. Qh7+ Kf6 7. Be3 Nf5 8. exf5 exf5 9. Bg5+
Ke6 10. Rd3
15 19:31 1/48 Nf3 >exit
local: t=19:40 nps=929521.0 n=1096719505 (18.3% / 81.7%) fh=88.7%
total: t=19:40 nps=929521.0 n=1096719505 draws=785261
trans: probes=200125712 hits=28654489 (14.32%) draft=19063560 (9.53%)
tcuts: exact=1612 (0.00%) upper=12071230 (6.03%) lower=4532855 (2.27%)
tstor: exact=2227 (0.00%) upper=75586719 (71.85%) lower=29619087 (28.15%)
ext: check=66673640 recap=2913070 ppush=150583 1rep=5403673 thrt=0
q-moves: gen=721824844 tested=355714766 made/un=139421024 max-dep=15
max eval diff: part-1=4.219 part-2=2.471
And with 96MB Hash:
Game stage: Middle game
Current eval: 0.276
Ply Time Score Nodes Principal Variation
4 0.02 +0.053 5730 Bd5 Ne7 2. Bb3 Bb7
4 0.04 +0.053 13473 Bd5 Ne7 2. Bb3 Bb7
5 0.05 +0.051 21854 Bd5 Bg4 2. Nf3 Qd7 3. c4
5 0.11 +0.121 64153 c4 Qe7 2. cxb5 axb5 3. Qh6 Bb7
5 0.12 +0.121 74296 c4 Qe7 2. cxb5 axb5 3. Qh6 Bb7
6 0.13 +0.070 91419 c4 Qe7 2. cxb5 axb5 3. Qh6 Be6 4. Bxe6 Qxe6
6 0.23 +0.070 171617 c4 Qe7 2. cxb5 axb5 3. Qh6 Be6 4. Bxe6 Qxe6
7 0.29 +0.046 238211 c4 Qe7 2. cxb5 axb5 3. Qh6 Be6 4. Bxe6 Qxe6 5. Rd2
7 0.52 +0.221 449463 Bd5 Bb7 2. Nf3 Qe7 3. Ng5 Bd6 4. f3
7 0.61 +0.221 529549 Bd5 Bb7 2. Nf3 Qe7 3. Ng5 Bd6 4. f3
8 1.22 +0.089 1045220 Bd5 Ne7 2. c4 b4 3. Ba8 Qa4 4. Rd6 Be6
8 1.58 +0.342 1392143 c4 Qe7 2. cxb5 axb5 3. Nf3 Bg4 4. Rd5 b4 5. Ng5
8 1.74 +0.342 1568623 c4 Qe7 2. cxb5 axb5 3. Nf3 Bg4 4. Rd5 b4 5. Ng5
9 3.03 +0.324 2786473 c4 Bb4 2. cxb5 axb5 3. Nf3 Be6 4. a3 Bxb3 5. Qxb3
Be7 6. Qe3
9 4.08 +0.324 3853992 c4 Bb4 2. cxb5 axb5 3. Nf3 Be6 4. a3 Bxb3 5. Qxb3
Be7 6. Qe3
10 6.95 +0.413 6619737 c4 Qe7 2. Nf3 Bb7 3. cxb5 axb5 {ht}
10 8.12 +0.413 7854794 c4 Qe7 2. Nf3 Bb7 3. cxb5 axb5 {ht}
11 19.35 +0.321 18387k c4 Bg4 2. f3 Bc8 3. cxb5 axb5 4. Bxf7+ Rxf7 5. Qxa3
g5 6. Nf5 Bxf5 7. exf5 Rxf5
11 32.73 +0.367 30994k Nf3 Bg4 2. Bd5 Qd7 3. h3 Bxf3 4. Qxf3 Bb2 5. Rb1
Ba3 6. c4 Bb4 7. cxb5 axb5
11 35.18 +0.367 33256k Nf3 Bg4 2. Bd5 Qd7 3. h3 Bxf3 4. Qxf3 Bb2 5. Rb1
Ba3 6. c4 Bb4 7. cxb5 axb5
12 57.74 +0.461 53719k Nf3 Bg4 2. Bd5 Qd7 3. c4 Bd6 4. h3 Bxf3 5. Qxf3
bxc4 6. Bxc4 Qb7 7. Qe3 Rb8
12 1:20 +0.461 75743k Nf3 Bg4 2. Bd5 Qd7 3. c4 Bd6 4. h3 Bxf3 5. Qxf3
bxc4 6. Bxc4 Qb7 7. Qe3 Rb8
13 2:21 +0.572 129371k Nf3 Bg4 2. Bd5 Qd7 3. c4 Bd6 4. h3 Bxf3 5. Qxf3 Qb7
6. cxb5 axb5 7. Qe3 Rc8 8. f3
13 3:32 +0.572 197857k Nf3 Bg4 2. Bd5 Qd7 3. c4 Bd6 4. h3 Bxf3 5. Qxf3 Qb7
6. cxb5 axb5 7. Qe3 Rc8 8. f3
14 6:43 +0.534 366445k Nf3 Bg4 2. c4 Be7 3. cxb5 axb5 4. h3 Bxf3 5. Qxf3
Qb8 6. Qe3 Bg5 7. Qxg5 Qxb6 8. Rd7 Qc5
14 13:34 +0.590 740192k Nxg6 hxg6 2. Qh6 Be6 3. Rd3 Ne7 4. Bxe6 fxe6 5. c4
Bb4 6. Rh3 Kf7 7. Qh7+ Kf6 8. Rf3+ Kg5 9. Be3+
Rf4 10. Bxf4+ exf4 11. cxb5 Qxb5
14 15:44 +0.590 858525k Nxg6 hxg6 2. Qh6 Be6 3. Rd3 Ne7 4. Bxe6 fxe6 5. c4
Bb4 6. Rh3 Kf7 7. Qh7+ Kf6 8. Rf3+ Kg5 9. Be3+
Rf4 10. Bxf4+ exf4 11. cxb5 Qxb5
15 16:33 +0.808 905376k Nxg6 hxg6 2. Qh6 Be6 3. Rd3 Ne7 4. Bxe6 fxe6 5. Rh3
Kf7 6. Qh7+ Kf6 7. Be3 Nf5 8. exf5 exf5 9. Bg5+
Ke6 10. Rd3
15 28:36 8/48 Qh6 >exit
local: t=28:44 nps=914734.1 n=1577230254 (18.8% / 81.2%) fh=88.7%
total: t=50:20 nps=917347.2 n=2770372839 draws=1298081
trans: probes=295112890 hits=47263845 (16.02%) draft=30542628 (10.35%)
tcuts: exact=1751 (0.00%) upper=20515177 (6.95%) lower=7145289 (2.42%)
tstor: exact=2231 (0.00%) upper=115980721 (72.48%) lower=44032417 (27.52%)
ext: check=110731856 recap=4367307 ppush=229280 1rep=8314320 thrt=0
q-moves: gen=998346416 tested=483364135 made/un=187711410 max-dep=15
max eval diff: part-1=4.219 part-2=2.471
Cheers, Tim.
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