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TCEC Season 14 – the 14th Top Chess Engine Championship

Tue, 03/12/2019 - 02:59

Written by Guy Haworth and Nelson Hernandez
Reading, UK and Maryland, USA

Corresponding author: g.haworth@reading.ac.uk

This is the latest in our series of analytical articles on past TCEC events. The main text can be read below on this webpage, and at the bottom you will find a link to the full layouted article in pdf format, including the important tables, graphs and images.

TCEC is very grateful to the authors for their kind permission to publish these substantial and scholarly analyses of its events!

Introduction

TCEC Season 14 started on November 12th 2018 and introduced a number of changes from TCEC 13 (Haworth and Hernandez, 2019b). An enlarged Division 4 featured twelve engines and seven newcomers to accommodate the increasing interest in computer chess and this competition in particular. The other divisions remained eight strong. The five divisions played two or more double round-robins (‘DRR’) each with promotions and relegations following. Tempi gradually lengthened from ‘Rapid’ to ‘Classical’, and the Premier division’s top two engines played a 100-game match to determine the Grand Champion.

The trio of STOCKFISH, KOMODO and HOUDINI have dominated the TCEC medals for several seasons and a key point of interest was whether others would reach the podium. LEELA CHESS ZERO and ETHEREAL were certainly expected to perform well in Division P, having shown remarkable improvement in the previous few months. KOMODO MCTS was a dark horse.

There were a few nudges to TCEC’s adjudication rules. Draw adjudication could be invoked after move 35 (rather than move 40) and the two engines had to both evaluate within ±0.08 (rather than ±0.05) for eight consecutive plies and with plycount≠0. While draw-adjudication requirements were relaxed, win-adjudication requirements were tightened. Engine evaluations had to be outside ±10 (rather than ±6.5) for ten consecutive plies (rather than eight); plycount was not a factor. This change was welcomed by those of us who wanted to see a clearer demonstration of superiority on the board: it will be interesting to see how long it prolongs the decisive games and what mysteries remain.

The common platform for TCEC14 consisted of two computers. One was the established, formidable 44-core server of TCEC11-13 (Intel, 2017) with 64GB of DDR4 ECC RAM and a Crucial CT250M500 240 GB SSD for the EGTs. The ‘GPU server’, a Quad Core i5 2600k, was sporting Nvidia (2019) GeForce RTX 2080 Ti and 2080 GPUs for those engines which could exploit them.

The engines

Season 13 competitors BOBCAT, DEUS X, HANNIBAL and SENPAI rested for this TCEC season. TCEC welcomed first appearances for engines DEMOLITO, KOMODO MCTS, PIRARUCU, ROFCHADE, SCHOONER, SCORPIONN and WINTER, see Fig. 1 and Table 1.

Division 4: 2 DRRs, 4 round robins, 264 games, 30′+10″/m

As for TCEC12/13, each engine played both White and Black from four-ply openings defined by the second author here. The results are as in Table 2: ‘P%’ is the %-score and ‘ELO±’ is the change to the engine’s nominal ELO based on its performance. Generic stats are in Tables 9 and 10.

Online interest naturally focused on the newcomers, especially KOMODO MCTS (Chessdom, 2019), a further innovation from the Lefler/Kaufman camp. The engines had a wide range of ability leading to only 34.1% of games being drawn: those given a default ‘TCEC-entry ELO’ of 2900 ranged across the field. WINTER was always headed for a demotion spot. SCORPIONN clearly was not ready for the contest and even though it disconnected eight times, it did not impact the ranking elsewhere. The bottom three missed TCEC Cup 2 (Haworth and Hernandez, 2019c). The three engines promoted were clearly ahead: KOMODO MCTS, ROFCHADE and NEMORINO.

Division 3: two DRR phases, 14 rounds, 112 games, tempo 30′+10″/m

Again, the eight engines involved played both sides of 14 prescribed four-ply openings. With GPU operating temperatures more stable, LCZERO was expected to do well after its performance in TCEC Cup 1 (Haworth and Hernandez, 2019a) and it did not disappoint, see Table 3. KOMODO MCTS also distanced the rest of the field and continued on up the divisions. Crashes remained a problem: this time, HANNIBAL incurred five. In game 26/7.2, ROFCHADE disconnected in a 7-man tablebase drawn position. In g93, NIRVANA retained the KBNPKRN draw for 101 moves but claimed the 50-move draw with 165. Bd6 – which loses to 165. … Nf7+ 166. K~ Nxd6. Do chess programs do irony?

Division 2: two DRR phases, 14 rounds, 112 games, tempo 30′+10″/m

Game 64/16.4, KOMODO MCTS – LEELA, ended in a rare stalemate on m172. Game 93/24.1, NIRVANA–LEELA, was drawn at position 115b but a mate for Black in 29 moves when the 50-move draw rule intervened. Demoted GULL beat BOOOT and BOOOT beat LEELA which otherwise moved smoothly away to win the division again, see Table 4. The silver medal went to KOMODO MCTS, courtesy of one less loss to LEELA than XIPHOS and one more win to the rest of the field.

Division 1: two DRR phases, 28 rounds, 112 games, tempo 60′+10″/m

The penultimate game 28.3/111 was the longest ever for TCEC Division 1 at 308 moves: ‘new wave’ LEELA versus ‘old guard, oldest brand’ FRITZ 16. The win is routine enough with rook and passed pawn against a half-sighted bishop but endgame solver FINALGEN (Romero, 2012) sees 20 moves before a clear win, a line that results in mate on move 337 at best (Haworth and Hernandez, 2019d).

GINKGO surprisingly crashed four times and was disqualified so the formal results are slightly different from those of Table 5 even if promotions/relegations are otherwise unaffected. FRITZ never saw a win in this company and also was demoted to division 2.

Division P, three DRR phases, 42 rounds, 168 games, tempo 90′+10″/m

The line-up for Division P had only a semi-familiar look. After the TCEC13 podium trio of STOCKFISH, KOMODO and HOUDINI, we had the other survivors FIRE, ETHEREAL and ANDSCACS. Interest however centered on the newcomers LEELA CHESS ZERO and KOMODO MCTS, both bringing MCTS search to the game. The contest was three DRRs rather than the four of TCEC13.

After the first round-robin, STOCKFISH had jumped out into the lead with four wins. After the first DRR, with colour-bias eliminated, STOCKFISH maintained a healthy lead and remained unbeaten, a feat shared with KOMODO and LEELA. Was the TCEC podium about to change? KOMODO MCTS had disconnected and lost twice against KOMODO in drawn positions. A third disconnection would be bad for both engines: disqualification for MCTS and elimination of Komodo’s crash-wins from the table.

Game 64 saw STOCKFISH beat KOMODO, opening the door for LEELA. In game 68 at the foot of the table, ANDSCACS beat ETHEREAL with Black. At the half-way point, LEELA was edging the contest for second place and remained unbeaten. The fourth round-robin saw LEELA consolidate its second place with four straight wins against the tail including one as Black against ETHEREAL. The competition for second place remained open as STOCKFISH finally ended LEELA’s unbeaten run in the last RR4 game, g28.4/112.

The fifth round-robin saw plenty of drama. LEELA lost as Black to both KOMODO and FIRE, the first having serious tie-break significance and the second being seriously unexpected. GPU fan-settings were thought to be a contributory factor but not enough to trigger replays. In game 33.1/129 v HOUDINI, KOMODO MCTS disconnected for a third time, was disqualified and relegated with its games discounted. Hopefully, Mark Lefler will sort out the technical problems for TCEC15. This restored LEELA to second place. With one round-robin to go, adjusted scores at the top were STOCKFISH well clear on 21, LEELA 16.5, KOMODO and HOUDINI 16. The second relegation spot was between ETHEREAL on 11.5 and ANDSCACS on 11.

Every win was now going to be a major event, especially as the last round of 28 games started with seven draws. KOMODO as White lost to STOCKFISH in g37.4/148. Both LEELA and KOMODO beat FIRE. In the penultimate game, KOMODO beat ANDSCACS: ETHEREAL breathed again, having narrowly survived without a single win in this division. In the last game, a cliffhanger, STOCKFISH searched the endgame tables a thousand times more than LEELA and thought it had a feasible advantage, but LEELA held out in KRPPKRP to draw on move 93.

The raw figures of Tables 6 and 7 need adjustment because KOMODO MCTS’ disqualification flipped the ranking at both ends of the table. In fact, STOCKFISH ultimately had 25 points, LEELA 20, KOMODO 19.5, ETHEREAL 14 and ANDSCACS 13.5. The ‘big three’ became the ‘big four’ but the Shannon-AB engine mould was cracked again: the still-improving LEELA had remarkably progressed from Division 3 all the way to the TCEC Superfinal.

As in TCEC13, a knockout event was interposed between this tournament and the Superfinal. Would the LEELA team roll out an improved network in preparation for the big finish? A hint came in a ‘bonus match’ between a more recent ‘LEELA 32585’ and ‘STOCKFISH 8’, the latter having only 12 threads and a 4M hash-table. This was an echo and ‘simulation’ of the ALPHAZERO–STOCKFISH match: LEELA won +24=71-5. We reported on TCEC Cup 2 separately (Haworth and Hernandez, 2019c).

The TCEC14 Superfinal match: 100 games, tempo 120′+15″/m

TCEC’s ELOs suggested a STOCKFISH win by eleven. However, both engines came to the board in new versions: the match was now STOCKFISH v190203 versus LEELA v20.2-32930. There was bound to be a clash of styles occasioned by the different modes of evaluation and use of hardware. This dynamic was eagerly anticipated with viewer numbers often topping 2000. Jeroen Noomen (2019) again created a suitable opening book, aiming as before for at least 20% decisive results. Assaf Wool returned from his ‘TCEC Cup break’ to comment on all the games. GMThechesspuzzler and Kingscrusher were active on Youtube (Wool (2019) picked out positions from games 7, 8, 10-11, 13, 16-17, 20-22, 25, 27, 29, 35, 41, 49, 53, 55, 58, 63, 65-66, 71, 75, 80, 85 and 87. Kingscrusher (2019) commentated on games 7, 10-11, 13, 16, 17, 53, 66 and 85. Games 2, 7-8, 13, 17 20, 29, 49, 65-66, 80, 85 and 100 were covered by GM Thechesspuzzler, 2019). Soren Riis provided the authors with detailed analysis of games 7-8, 20-22, 65-66 and 71 which we provide via our pgn file for reader convenience rather than here. GM Matthew Sadler (2019), having analysed the STOCKFISH–ALPHAZERO games (Sadler and Regan, 2019) has also contributed his own view of this Superfinal.

The play and the results did not disappoint. STOCKFISH opened its account with wins from games 7 and 10 but LEELA replied with wins from games 11 and 13. There were twelve wins in the first thirty games, a hit rate of exactly 40%, see Table 8 and Fig. 2. At this point, the score was 15-15, suggesting that this would be the closest TCEC Superfinal since Season 5 in 2013 even though LEELA had never led. The same situation appertained at 24-24 after a run of 19 draws (not a record: the TCEC8 KOMODO 9.3x – STOCKFISH 021115 Superfinal games 14-37 and 47-71 were all draws). At this point, LEELA dramatically jumped out front with wins in games g49 and g53. This lead held until game 80 which STOCKFISH won. Ultimately, it was the single 0-1 win in another sea of 19 draws that allowed STOCKFISH to retain the title. Each game was closely contested with average length being one ply short of 100 moves – and not just because LEELA was reluctant to visit the draw zone.

Of course, suitably equipped grandmasters could write a book about this entirely gripping match and this would be most welcome. Here, we can only pick out a few chessic highlights which perhaps complement the analyses of the commentators above.

The hints from the evaluations of STOCKFISH suggest that it welcomed LEELA’s 15. Bb2 (g07), 51. … Be3 (g08, a missed win), 34. Kf1?? (g21) and 31. … Qd6 (g22). In game 35, 29. Ke1 rather than h7 seemed to lose LEELA’s winning advantage. Game 58 was adjudicated with a rare ‘mate in one’ on the board: the camera cut away just before the blow was struck. Game 63: LEELA was happy to trade pawns for position as early as eleven moves into the play. STOCKFISH did not see a serious problem until six moves later. LEELA create a passed pawn despite being three pawns down and this led to a crushing 41-move win, the shortest of the match.

If there was a pivotal juncture in this Superfinal, it was games 65-66 – a crucial one or two-point swing to STOCKFISH. In game 65, LEELA missed a KNP(c4)P(d5)KBP(c5) win with the winning capture admittedly 26 moves down the line (de Man, 2018). STOCKFISH clearly saw it was lost and LEELA would have been awarded the win under the TCEC13 ‘6.5+’ win-adjudication rule. LEELA was within 11 ply of winning with 9 ply to go and it is worth speculating as to how soon it would have found the winning idea, K on b5/c6 before Nxc5, had the plycount not intervened. Game 66 had to be restarted after two server crashes before LEELA – lost. Had it been possible to return to the game-state after the last completed move, the temperature of the partisanship in the chat room would have been lower. A minor cost, but transaction-checkpoint/restart might be applicable here.

Game 85 was the final win: the 12-move King’s Indian opening had already defined the major asymmetry of Queen versus BBPP. LEELA went from apparent equality to negative territory by move 25. Ultimately, LEELA’s QR were unable to prevent mate by a BBNNPP team, only five moves away when the referee stepped in. Game 86 was the longest ever TCEC game at 362 moves.

The Bonus 4-way and 2-way Rapid events

TCEC treated us to two bonus events at the Rapid tempo of 12′+3″/move. The first featured the top four - HOUDINI, KOMODO, LEELA CHESS ZERO and STOCKFISH: 20 DRRs, 40 round robins, 120 rounds and 240 games. STOCKFISH had a good first half and was never headed even if pursued closely by LEELA. HOUDINI and KOMODO tailed off, eventually in that order as KOMODO fared poorly in the second half. ELO-predicted net scores were +9/+1/-2/-8 but ‘actuals’ were +12/+6/-7/-11. The longest wins were g116.1 (1-0, 139 moves) and g37.2 (0-1, 125m): the longest draw, g12.1 (318m). Game 18.1 between Leela and Komodo was something of an anti-climax as a 3x-repetition draw after ten played moves. Full details are included with the repository e-version of this note (Haworth and Hernandez, 2019d).

The second event was a 100-game STOCKFISH–LEELA match from the initial position: no prescribed openings. LEELA won 16-4, perhaps by being single-minded about its openings (Wool, 2019).

Summary

The Google DeepMind company in St. Pancras, London have been remarkably open in sharing the core ideas of their intelligence initiative. In the year it has taken for DeepMind’s papers on ALPHAZERO (Silver et al, 2017/18) to mature and satisfy the referees, we have seen TCEC invest in Nvidia GPUs and foster several innovations going beyond the classic Shannon (1950) minimaxing AB model of a chess engine. We have seen a leading chess-engine author, Mark Lefler, move his focus successfully from top engine KOMODO to KOMODO MCTS (Chessdom, 2018). With one less technical break, this engine would have come all the way through the divisions to fully justify its place in Division P at the first attempt.

We have also seen a community come together to support and train the open-source LEELA CHESS ZERO echo of ALPHAZERO. Again, this has been rewarded by success, and how. LEELA edged out KOMODO and HOUDINI to take the challenger’s place in the Superfinal here. It was not expected to beat STOCKFISH but came within one game of drawing the classic phase.

Chess24 and Chessbomb, with its useful colour-coding of moves, covered the TCEC14 Superfinal so we were treated to kibitzing by three different, objective but hardly neutral versions of STOCKFISH. The Twitch TCEC channel claims that viewers’ computers have to date had a window open to TCEC Seasons 10-14 for a total of over half a million hours.

REFERENCES Full article

To read the full article in pdf, click HERE

published March 11, 2019

Categories: Ενημέρωση

TCEC Season 15 – To A/B or NNot to A/B, That is the Question

Tue, 03/05/2019 - 17:14

Season 15 of the Top Chess Engine Championship will begin this March 5th at 20:00 CET. It will feature a record number of engines to accommodate the booming sector and a record ELO of the participants. A total of 44 engines will face off in a division based system to determine the current status quo of strength and the grand champion of TCEC.

Stockfish has dominated the Top Chess Engine Championship for four consecutive seasons or a total of 10 months. It has a chance to expand this dominance in Season 15 for over 1 year (see the analysis of GM Matthew Saddler). Stockfish will have to show its best as significant challenge is coming from DeepMind’s Alpha Zero open source sister Leela Chess Zero. LCZero applied significant pressure in the S14 Superfinal, losing by a narrow margin 49,5-50,5. It also convincingly won its first major title the TCEC Cup and the inter season rapid bonus, thus showing high inspiration and determination for the title. These two engines, however, cannot relax, as Komodo with its innovative MCTS version and all other engines from the higher divisions will also bring in their best. Additionally, a new unique supervised learning neural network Allie+Stein will start from the bottom division and is aspiring to attack the top from its very first season.

Where to follow the Top Chess Engine Championship?

The Top Chess Engine Championship has a dedicated website with games going on 24/7 at http://tcec.chessdom.com . You can enjoy the games with live commentary by BlueFish (Stockfish running on 172 cores, represented by a blue line on the graph), Redmodo (Komodo on 128 cores, represented by a red line on the graph) and chat with engine authors, computer chess experts, and friends in the ever lively TCEC chat.

The previous season was record breaking in audience, including in the video broadcast of the event. A total of 500 000+ viewer hours were registered in the past 30 days, which is #1 position on Twitch among the chess channel, and higher than 50% of the total chess audience viewership altogether. You can follow the alternative video broadcast at TCEC Twitch TV

TCEC is the most watched chess channel and competition by far, according to the official Twitch Metrics

Growth of TCEC session viewers season by season from 2015 to 2019 visualized by Google analytics. S14 was a !boom (click on the image to expand)

TCEC Season 15 participants

Premier Division

1. Stockfish
2. LCZero
3. Komodo
4. Houdini
5. Fire
6. Ethereal
7. Promotion from Div 1
8. Promotion from Div 1

Division 1

1. Andscacs
2. Komodo MCTS
3. Fizbo
4. Chiron
5. Laser
6. Jonny
7. Promotion from Div 2
8. Promotion from Div 2

Division 2

1. Fritz
2. Ginkgo
3. Xiphos
4. Booot
5. Nirvana
6. ChessBrainVB
7. Promotion from Div 3
8. Promotion from Div 3

Division 3

1. Gull
2. Texel
3. Arasan
4. Vajolet
5. Pedone
6. rofChade
7. Promotion from Div 4
8. Promotion from Div 4

Division 4

Division 4 of the Top Chess Engine Championship will evolve this season 15. It will expand to accommodate all engines that are active and have ELO above 3000. It still remains testing ground for new engines and as support for the computer chess field, however, one cannot ignore that from this division have started engines like LCZero, Komodo MCTS, Ethereal, ChessBrainVB, etc.

Division 4 will be with two groups, !division4a and !division4b. Each will contain ten engines that will play a 1xDRR tournament with time control 30 min + 5 sec. The top two engines of the groups will promote to a playoff – !div4playoff. That will be a 2xDRR event which will determine the two engines advancing to Div 3.

Here is the full list of participants

Division 4 A

1. Winter
2. Tucano
3. Topple
4. Rodent III
5. Nemorino
6. The Baron
7. Cheese
8. Igel
9. Minic
10. RubiChess

Division 4 B

1. Pirarucu
2. Allie+Stein
3. Wasp
4. Chess22k
5. Marvin
6. Monolith
7. ScorpioNN
8. Jumbo
9. Bagatur
10. Gaviota

Rules and regulation changes for Season 15

The rules set of TCEC advances one more step this season 15, to resolve specific cases that arose in previous seasons. Besides the expansion of Division 4, here is what will change in all divisions:

* Increment in Div P, Div 1, Div 2, Div 3, and Div 4 will be 5 sec per move. The Superfinal increment is reduced to 10 sec per move

* Black wins will be removed from the tiebreak criteria, due to the usage of advanced books. The order of tiebreak criteria is as follows 1: # of crashes. 2: Direct encounter. 3: # of wins. 4: SB. 5: TD decision

* In case of a server disconnect or other interruption not caused by the engines:
**If the web server crashes, the game continues unaffected, and broadcasting will be resumed as soon as possible;
**If the evaluation of both engines is >=ABS(10) at the moment of game server interruption, the game is scored as a win ;
**If the evaluation of both engines is <=ABS(0.10) at the moment of game server interruption, and both engines have completed 35 moves, the game is scored as a draw;
**If a game interrupts with 7 pieces on the board, position on the board at the instant of game server interruption will be adjudicated according to 7-man EGTB.
** In all other cases the game is restarted from the position that the two engines reached before the disconnect, with time compensation to fill up the cache

* The top 4 engines of !div4a and the top 4 of !div4b, so 8 in total, qualify for the TCEC Cup. The engines in the playoff are seeded by their final standings, the other ones are placed on a random draw seeds 29-32

There will be no change of the 3 strike out rule this season, due to the multiple cases that have to be covered. An engine update during a division will count as a strike.

The engine uniqueness requirement stays intact , as worded in the S14 rules and regulations.

Categories: Ενημέρωση

Allie+Stein, the new neural network entering TCEC S15

Sat, 03/02/2019 - 22:25

The new neural network entering TCEC Season 15

Season 12 of the Top Chess Engine Championship saw the arrival of NN engines, modeled after DeepMind findings Alpha Zero, into public computer chess events. At that season LCZero played with CPU only. In Season 13 it was handed a GPU, and only a season later that neural network won its first major title.

Besides LCZero, one more neural network entered TCEC. It was Scorpio NN by Daniel Shauwl. And even though it did not make it past Div 4, it showed a trend in computer chess: people understood the potential value and advantages of neural networks in chess.

Season 15 is about to start and one more neural network is going to enter TCEC. This is a combined project by Adam Treat and his Allie and Mark Jordan and his Leelenstein. The new engine is called Allie+Stein, a unique engine by the TCEC rules that will start its quest for top positions and climb of the ladder from Division 4.

Here is an extensive interview with the authors Adam Treat and Mark Jordan.

Season 15 of TCEC will start this March 4th, live on the official website of TCEC and the TCEC Chess TV.

Your engine Allie+Stein will be the new neural network in TCEC, making its debut this Season 15. Welcome to the Top Chess Engine Championship!

Adam Treat: Allie is a very new chess engine, but represents a lot of hard work over the last several months, so I’m hoping TCEC can provide an opportunity to see how she stacks up against a host of more established engines. Combining Allie with the Leelenstein network will also be interesting given that both introduce new avenues of research in NN chess engines. I an new to the chess programming community and culture and so I am excited to participate and learn through TCEC.

Mark Jordan: I am excited to see how far an engine that uses supervised learning (SL) exclusively can go and I hope there will be more strong SL networks to compare against for benchmarking average performance and maximum performance of the method.

So far there have been two unique NNs in TCEC – LCZero and Scorpio. What makes your engine the third unique NN engine by the TCEC rules

AT: Like Leela, Allie is based on the same concepts and algorithms that were introduced by Deepmind in the AlphaZero paper(s), but her code is original and contains an alternative implementation of those ideas. You can think of Allie as a young cousin of Leela that can utilize the same networks produced by the Lc0 project or other compatible networks. The Leelenstein network is also a novelty in that it introduces supervised learning into the TCEC competition. Finally, Allie+Stein will be using MCTS for the beginning portions of the tournament, but I’m hoping to switch to AlphaBeta search during later rounds… if she makes it that far :)

MJ: Allie+Stein is a completely new engine and neural network produced, thus easily satisfying 2 out if the 3 conditions for uniqueness. It is possible eventually that I will rewrite the training scripts completely with some more new ideas in the future. Currently, training has some changes to the Leela training scripts.

Can you share more on how is Allie+Stein engine being trained?

MJ: Training started from a random initialized network, and consisted of mostly CCRL computer games (I used all of them available), and some weak Leela t30 games and some games from other experiments I was able to gather. These were were all about 100 elo weaker than t10. I tried several new learning techniques using these same games. My goals have mostly been focused on NN learning experimentation. I compared the learning schedule and optimizer that Leela used to different ones from some academic papers, and it seemed to improve performance, but it was still about 50 elo weaker than the best Leela nets. So I replaced all the weak t30 games with many more recent ones, using all of January’s games, while still keeping the CCRL games in the training window, and continuing on several more of my cyclical learning rate cycles.

And how about search?

AT: To begin the tournament, Allie will perform MCTS based search with absolute fpu where new nodes start off with win pct of -1. The search is modeled after Deepminds paper’s. As I said above, I’m hoping to switch to AlphaBeta for the long term direction of the project. I’ve experimented with many, many ways of doing this with the networks generated by the Lc0 project and I think I’ve hit upon a way to achieve the depths required to maintain ELO level with MCTS based search, but it is not ready yet. In the future, I imagine we’ll see a lot of experimentation with different variations of search (mcts, ab) + eval (handwritten, NN) in computer chess engines. Hoping to be a part of that and to contribute to the shared pool of knowledge.

What is the strength of Allie+Stein? What division do you expect to reach? Do you think stronger versions will come out as the season progresses and thus have a better shot at the Premier Division?

MJ: I think the neural network seems to scale pretty well with more nodes. In bullet testing it loses to Stockfish quite a bit, but seems to hold its own in tournaments with more time. I believe it has potential to get to division 1, but will require some more work to better utilize multiple GPUs and support tablebases. I have some ideas to use tablebases in learning as well that could end up making the neural network Premier Division material. But for this season I will be happy even with just getting to Division 2.

AT: This is a question I get quite often. Most people familiar with chess engines know that it is extremely hard to compare strengths other than through heads up competition with a set of match rules/controls in place. That is exactly what TCEC provides. A levelish playing field and a set of machines/rules agreed upon beforehand to determine the relative strength of different algorithms and their implementations. So with a huge grain of salt I’ll say that on my own rather meager hardware I have experienced heads up matches between Allie and Lc0 at short time controls with the same network with a relative difference of 50-100 elo in Lc0′s favor. Obviously, that is with only one GPU. Throw in the advanced multi-gpu hardware here at TCEC and that is a very big new variable. Add the other engines and we have another large unknown variable. Add in that we’ll be using a Supervised Learning network and yet another big variable. Then we have the fact that Allie will start off the tournament without TB support. Just lots and lots of variables. So, ok I expect she will be able to advance out of Div 4, but anything is possible. I’ll be happy if she is able to get winning positions and mate consistently in them :)

Comparing to the top NN engine now Lc0 , do you expect with your approach to have better future?

MJ: The beauty of my approach using only existing games is I can train whole new networks from scratch in a week or two to try a new idea, something that would take the Lc0 project several months, even with 100x or 1000x more compute than I have. I hope to eventually show that some of my ideas must be good by how strong the network is and Lc0 can try them to become strong as well. And I will also continue to try good ideas from there as well. And the project is a great resource for people who need many millions of strong games, as it already has many more games available than all of CCRL even though it is much younger. And sadly fishtest doesn’t store and host all of its games. So I expect to see some great symbiosis.

AT: I expect that whatever advances are made by one engine will (with time and effort) be incorporated into other engines. As they should be! We are all standing on the shoulders of the pioneers in computer science and chess engine programming that came before. I do think that AlphaBeta is a superior search method and that there is no reason that an AB+(eval method) engine can’t compete favorably with an MCTS+(eval method) regardless the eval method. But this is just my theory and worth very little until proven. Only the future will tell.

What are your thoughts on the current hardware balance at TCEC? Are you happy with the hardware your engine is going to play on?

MJ: There are always debates about hardware balance, and I think a wide range power’s are somewhat fair, and as long as the specifications and NPS numbers are published and maintained throughout the tournament it is a reasonable tournament data point. The balance seems to be within a 2x order of magnitude of fair based on any of purchase price, watts, and total cost of ownership metrics which I think is as close as it can possibly get to please everyone. But it does leave room for future debate and improvement. 2x the power or cost doesn’t translate to 2x the nodes so the real elo difference is probably not enough to change what division any engine will end up in most cases, even if it changes a result or two. The format is not guaranteed to find 20-30 elo differences anyway, so I don’t see it as a big issue except during boring games :)

AT: Considering that I’ve never personally tested Allie on this level hardware, sure I’m happy. I just hope she scales well enough.

Read: Stockfish dominance continues and Analysis by GM Matthew Sadler

Stockfish has been dominant at TCEC for almost 1 year.

AT: Stockfish is the strongest engine until proven (convincingly) otherwise. I have great respect for all the developers who work on Stockfish (and other engines for that matter) and think the community of chess programmers is pretty collegial.

MJ: I very much support non-private engines, so I am glad to see that there has never been a private engine to win the Superfinal. And even more glad that it seems that free and even open-source projects can win. I am glad such excellent chess is truly accessible to all.

Read: interview with Alexander Lyashuk

Alexander Lyashuk from Lc0 shared in an interview that he expects at least 5 NNs to appear and they to dominate computer chess. Do you share this vision? Do you expect one of those NN engines to be Allie+Stein?

AT: I do think it is only a matter of time before NN eval is shown to beat handwritten eval regardless the search method. Right now, if you limit the number of nodes – hands down – any of the NN’s will beat the traditional handwritten eval engines. This is just a fact. Still, I have great respect for the ingenuity of those writing the traditional engines. I hope Allie+Stein will be a meaningful engine in terms of helping to advance the state of art in computer chess programming in the near future.

MJ: As I mentioned above, I am excited to see more projects, and I hope there will be enough of them that we have to pick the most exciting and unique ones. We can use them to develop more tests to determine how unique they are in their ideas of openings and in general play, and which ones are truly beyond average. Of course I hope to have one of these beyond, so the top 5 sounds nice!

Categories: Ενημέρωση

The TCEC14 Computer Chess Superfinal: a perspective

Sat, 03/02/2019 - 02:56

The TCEC14 Computer Chess Superfinal: a perspective
by GM Matthew Sadler
London, UK

Season 14 has been amazing! The clash of styles between STOCKFISH and LEELA produces consistently interesting chess – just like the match between STOCKFISH and ALPHAZERO did. You really hope that this sort of clash of styles can continue for the next few seasons.

Just a few impressions about the games. I was really impressed by LEELA’s handling of the White side of G17, the Budapest. I’ve done a fair amount of analysis on this line and a few good players have got stuck against it. Aronian defeated Ivanchuk in 2013 at the London Candidates but more due to Ivanchuk’s terrible time trouble than due to getting anything out of the opening. Giving the c-pawn back very quickly is a great way of putting the pressure right back on Black. I also liked G45 a lot: a Hedgehog where LEELA generated a huge amount of play with some risky but incisive pawn play on both sides of the board. The LEELA win in G53 was extremely nice too: again, it’s impressive to see Black being stretched so greatly with rook’s pawn thrusts on both sides (18. a4 and 23. h5) then a thrust of the g-pawn (24. g6) followed by returning to the queenside with 28. c4. This sort of whole board vision is what grabbed me so much when I first played through ALPHAZERO’s games – the game ‘exactly how to attack’ (Sadler and Regan, 2019) is the best example of this – and it makes for wonderful chess when you have a player who can execute it so well.

I found G62 incredible: the move 10. … 0-0-0 would never have occurred to me! In some ways, I felt that LEELA was playing like STOCKFISH – grabbing a hot pawn and betting on surviving with a rather dodgy king – and STOCKFISH was playing like LEELA – sacrificing a pawn for open lines against the king. G63 was magnificent: perhaps the most ALPHAZERO-like game of the whole match. Material balance is not important, accurate assessment of an opposite-coloured bishop position, restriction of the opponent’s king, entombing of the Black rook on h8 (a little like the game ‘Python squeeze’ featured in Game Changer). It’s a classic game: it was wonderful to watch and I’ve played through it a few times since with great pleasure. G66 was a wonderful effort from STOCKFISH. It followed a STOCKFISH–ALPHAZERO game until move 16 in which ALPHAZERO was also under great pressure and the power of STOCKFISH’s attack was huge! G81 and G82 (the opening part) was a great pair of games in a sharp Slav gambit. G81 was particularly nice with rook’s pawn thrusts on both sides of the board from LEELA to tie Black up on the queenside – even at the cost of another pawn – while LEELA targets the kingside (it’s another theme you see quite often in ALPHAZERO’s games). G85 and G86 (the opening part) were also fantastic. STOCKFISH handles these positions with so much energy: quite amazing!

REFERENCES
Sadler, M. and Regan, N. (2019). Game Changer, esp. pp 38-43 and 99-100. New in Chess.

Communicating author: https://matthewsadler.me.uk/

Categories: Ενημέρωση

Stockfish continues to dominate computer chess, wins TCEC S14

Fri, 03/01/2019 - 23:05

The collection of Stockfish gold medals – six times winner of TCEC and one time winner of the Cup

Stockfish continues to dominate computer chess after defeating LCZero at the Superfinal of Season 14 of the Top Chess Engines Championship. This is a fourth consecutive title for the open source engine – after winning Season 11 of TCEC last April 2018, Stockfish never let go the title.

This time, however, it was a really close fight. Until the very last game the match could go in any direction. In the end Stockfish won 50,5-49,5 (+10 =81 -9).

Stockfish wins TCEC S11 / Stockfish wins TCEC S12 / Stockfish wins TCEC S13 / Stockfish wins TCEC S14

More about S14: Stockfish wins the Premier Division / LCZero wins the Cup / First major title for Leela / Interview with Alexander Lyashuk / Komodo MCTS – interview / TCEC S14 preview

 

Note: TCEC Season 15 starts this March 4th, you can watch it on the official website or at TCEC Chess TV

Bright start at the Premier Division

Defending its title by Stockfish in Season 14 started in the Premier Division. There Stockfish was merciless – it qualified for the Superfinal as clear first and without losing a single game. Considering this was the strongest Premier Division in the history of TCEC, the achievement of Stockfish may remain a unique feat for many seasons to come.

The Superfinal battle

For the first time in many years, the dominance of the big 3 – Stockfish, Komodo and Houdini – was disturbed this Season 14. The world’s strongest open source neural network LCZero managed to outwit both Komodo and Houdini and grabbed a last minute ticket to the Superfinal by finishing second at the Premier Division.

Few believed that LCZero could put up a serious fight in the Superfinal. The dominant performance of Stockfish in the Premier Division and the shaky play of LCZero were pointing towards a landslide victory for the reigning champion. But every chess fan was in for a surprise – LCZero entered an experimental network , which utilized the latest findings by DeepMind. The result was astounding – the Superfinal turned out to be the most contested TCEC title in the history of computer chess.

In the first three pairs of games – QGD, Tarrasch (von Hennig-Schara gambit), Sicilian, Najdorf (Byrne English attack), and King’s Indian (5.Nf3) – LCZero put up a serious fight and a good understanding of the position. The first decisive blow came in game 9, Stockfish caught LCZero unprepared in a King’s Gambit line.

Replay: Lc0 – Stockfish – King Gambit Accepted, Schallop defence 0-1

Right in the next pair of games, Stockfish converted its game with white in the Catalan opening, increasing the score to 2-0.

Replay: Stockfish – LCZero – Catalan opening

Just as everyone was saying “this is the beginning of the end of the Superfinal”, LCZero returned a game in the French, Tarrasch (Guimard main line) and yet another in Nimzo-Indian, classical (Pirc variation).

Replay: LCZero – Stockfish – French, Tarrasch (Guimard main line) 1-0
Replay: LCZero – Stockfish – Nimzo-Indian, classical, Pirc variation – 1-0

After an exchange of blows in game 16 and game 17 , it was time for Stockfish to speak – 3 consecutive wins!

Replay: Stockfish – LCZero (Ruy Lopez) 1-0
Replay: LCZero – Stockfish (Ruy Lopez) 0-1
Replay: Stockfish – LCZero (English, Bellon gambit) 1-0

One more time the same question, is this the end of the match? No! LCZero needed only 8 games to erase the three points advantage and level the score

Replay: LCZero – Stockfish – QGD, semi-Slav 1-0
Replay: LCZero – Stockfish – Pirc defense 1-0
Replay: LCZero – Stockfish – Dutch 1-0

Nineteen consecutive draws followed in which both engines had chances to score. LCZero was the last one to score before halftime, in a Benoni game

Replay: LCZero – Stockfish – Benoni 1-0

Thus, the two engines finished equal in the first half of the TCEC Superfinal. This was just a virtual mark, but now everyone was convinced – this Superfinal will not resemble anything seen before.

The exchange of blows continued with LCZero taking the lead:

Replay: LCZero – Stockfish – QGD Slav, 4.e3 Bf5 1-0
Replay: Stockfish – LCZero – King’s Indian, Kramer system 1-0
Replay: LCZero – Stockfish – French, MacCutcheon, Janowski variation 1-0

A decisive moment in the match came in games 65. LCZero created a winning position – Stockfish showed +153.1, showing that there is a tablebase win in this position. However, that was a 7 pieces tablebase win and no automatic adjudication happened. Rather the game continued and LCZero did not manage to convert.

Had it been a previous season, the game would have been adjudicated under the tournament rules that if the engines agree on a +6,5 eval for a certain number of moves the game is automatically scored. Under the new rules of Season 14, the engines were forced to show more understanding as to how to convert a given position, triggering the rule after a +10 eval. LCZero’s +8.92 evaluation was not enough and a virtually won game finished in a 50-moves rule draw.

Replay the dramatic game 65

Although this game will remain in the history of computer chess as one of the most dramatic games ever witnessed, the match was far from over as 35% of the games were still to be played. The tension increased game after game – LCZero was building up advantages, but Stockfish as a true “minister of defense” was bringing the games to equal score. What’s more, Stockfish started converting its own advantages and turned the match around.

Replay: Stockfish – LCZero – Queen’s Indian 1-0
Replay: Stockfish – LCZero – Sicilian 1-0
Replay: LCZero – Stockfish – King’s Indian 0-1

With that last win with black Stockfish took the lead in the match and did not let it go until game 100. A very difficult match for both sides which certainly deserved the popular name “first match of the end of an era”. So far the era of Stockfish continues full steam ahead. Season 14 is over with a fourth consecutive title by Stockfish. But there is no time to relax as Season 15 starts this March 4th – with a record number of engines, a new neural network, and the highest ELO ever seen in computer chess.

Follow the action live on the official website of TCEC

Categories: Ενημέρωση

Tiebreak looming at the TCEC Superfinal

Wed, 02/20/2019 - 22:42

Last November, the classical World Chess Championship between Magnus Carlsen and Fabiano Caruana was an amazing adventure of total equality – twelve consecutive draws and a need for a rapid tiebreak. Magnus Carlsen won the World Chess Championship 2018 title and many experts predicted that such an equal match will not be seen in the near future. They have all been proven wrong, as just several months later we are seeing a match for a world title which is more equal and for many fans it is dubbed as more dramatic.

84 games into the final of the Top Chess Engine Championship, the premier event for chess software, the reigning champion Stockfish and the challenger Leela Chess Zero are protagonists in an amazing battle. Despite the frequent exchange of blows between the two participants (a total of 18 decisive games!) the score is equal 42-42. A remainder of just 16 out of the total 100 games is left and the drama ensuing is unseen so far in the history of computer chess.

Leela Chess Zero entered the Superfinal as second in the Premier Division and as a TCEC Cup champion. It is the first neural network to ever reach the final for the highest chess engines title. Yet, in a poll before the match only about 35% of over 1000 people believed that LCZero had a chance, and of those people many admitted they chose the option just to support the engine as fans. When LCZero started winning games the surprise was huge and sent ripples through the chess world.

Only 16 games are left and anything is possible in the first “end of an era” match. Follow them live on the official website

TCEC Superfinal tiebreaks

The equal score after 84 games triggers high expectations for tiebreaks. In case of an equal score after game 100, there will be a rapid match of 16 games with a time control of 25′ + 10″ with random openings selected from earlier in the same Season. In case it is still tied there will be a Blitz match of 8 games with a time control of 3′ + 2″.

Bonus rapid match ?

There is also the possibility that one of the engines will prevail in the remaining classical games. In such a case, TCEC has prepared a bonus event for those fans that want to see a rapid event. It will be a one week event between the end of the Superfinal and the start of Season 15 Div 4 and will have the following rules:

* Four engines will be invited – Stockfish, LCZero, Komodo, and Houdini
* A total of 20 double round robins will be played
* The time control will be 12 min + 3 sec
* The first two engines in the standings progress to a 100 games rapid final

The rapid tournament will be played just for bonus purposes and fun. The real high quality chess happens only at long time controls, which allows the engines to show their best. Yet, it will be a fun event that many of the fans that enjoy the Superfinal would like to see.

Categories: Ενημέρωση

TCEC Cup 2 report

Wed, 02/13/2019 - 00:46

Written by Guy Haworth and Nelson Hernandez
Reading, UK and Maryland, USA

This is the third in a new series of analytical articles on past TCEC events. The main text can be read below on this webpage, and at the bottom you will find a link to the full layouted article in pdf format, including the important tables, graphs and images.

TCEC is very grateful to the authors for their kind permission to publish these substantial and scholarly analyses of its events!

Introduction

The knockout format of TCEC Cup 1 (Haworth and Hernandez, 2019a/b) was well received by its audience and was adopted as a regular interlude between the TCEC Seasons’ Division P and Superfinal. TCEC Cup 2 was nested within TCEC14 (Haworth and Hernandez, 2019c/d) and began on January 17th 2019 with 32 chess engines and only a few minor changes from the inaugural Cup event. The ‘standard pairing’ was again used, with seed s playing seed 26-r-s+1 in round r if the wins all go to the higher seed. Thus, seed s1 plays s32, s16, …, s2 if all survive long enough. STOCKFISH was top seed as the TCEC Cup holder but would have been anyway because of its TCEC14 placing as used for the other engines. It is worth noting that the TCEC14 discounting of HANNIBAL’s games because of ‘technical breaks’ affected others’ seeding. PEDONE was s23 rather than s21: ARASAN and VAJOLET stepped up one, given the residual points and tiebreaks. Fig. 1 depicts the logos of the engines in seed order. Basic engine details have been published elsewhere (CPW, 2019; Haworth and Hernandez, 2019d) but some fourteen engines as indicated in Fig. 2 were upgraded for the Cup, again a testimony
to the energy and enthusiasm of their authors.

The format was of 8-game matches at the Rapid tempo of 30′+5″/m rather than the ‘+10″/m’ of TCEC Cup 1. This time, all eight games were played whatever the running score. Openings were repeated with colours reversed after every odd-numbered game. The first few ply in all games were randomly selected from two sets of openings created by the second author here, their relative frequency reflecting that seen in human play: over 200 four-ply openings constituted the repertoire for the opening round of 32 and over 300 twelve-ply openings served thereafter. Tiebreaks were resolved, this time at end of round, by further pairs of games with openings after game 16 from 232 TCEC Superfinal 9-13 options. There was no Armageddon backstop even though the longest TCEC Cup 1 match went to 20 games. Adjudications were as for TCEC14.

As in TCEC Cup 1, interest focused on actual performance ‘%P’ compared with expected performance ‘E%P’ implied by TCEC ELO difference ‘ELO Δ’. The accuracy of the TCEC ELOs, the upgrades to nearly half the field and the character of the random openings would be the main influences.

Round 1

As expected, STOCKFISH opened its campaign with an 8-0 salvo. ‘LC0’ LEELA CHESS ZERO also achieved this feat but was notably more cautious in securing its wins, preferring the gentle ascent of sunlit uplands to a knife-edge scramble up a slippery mountain ridge with its greater risks. A newly refreshed ETHEREAL also scored the whitewash that three higher seeds did not. KOMODO, HOUDINI (twice), FIRE, CHIRON, LASER, FRITZ, GINKGO and remarkably, middling seeds XIPHOS and BOOOT qualified without losing a game. JONNY staged the one ‘come from behind’ victory at the last gasp, winning games seven and eight against ARASAN. The only upset of the seedings came in the third match, new-version ROFCHADE scoring 4½ rather than an expected 1½ and furthermore, ensuring that TCEC14 Division 3 would be represented in the second round.

Surprisingly, there were no ‘Act II’ tie-breaks to play out, perhaps because of the halved 5 move-increment. However, Round 2 was delayed by the setup and replay of the HOUDINI match, this time featuring the submitted WASP 3.54 which had, in error, not made it to the board in the normal course of events. Both matches are included in Table 1. The openings used were different but the end result was the same and even more in HOUDINI’s favour.

Round 2

Eleven of the sixteen victorious engines were sporting new versions for this event so TCEC’s ELO ratings were going to get a more severe examination. Only FIZBO was missing from the fancied half of the line-up. At this point, the second author here drew on his bank of 12-ply rather than 4-ply openings, arguably to the disadvantage of LC0 according to its proponents.

STOCKFISH opened the round as befits the Cup holder – 7-1, the ELO prediction. Game five ended in repetition after only ten calculated moves when the engines bit on a Pringle, a saddle-shape in their joint evaluation surface. GINKGO scored two firsts, one bad one good: the first ‘disconnect’ of the event and the first round two win by the underdog, albeit after the match was decided. The team of unfancied seeds did better than par but still, they all lost: there were no ‘come back’ wins or tiebreaks.

The quarter-finals, semi-finals, small final and final

The locker room for the quarter-finals therefore had the look of a Division P reunion, the top eight seeds perhaps thinking of negotiating their own TV contract. Who knows where AI may lead. STOCKFISH came through easily enough and again without loss but just short of ‘ELO expectations’. HOUDINI and FIRE also came to their match without a loss: something had to give. In their last 22 TCEC games, HOUDINI was +2=19-1 but FIRE came in a new version. The result was the first 4-4 tiebreak, indeed a deadlock of 8 draws – an echo of Carlsen-Caruana, 2018. The tiebreak was played after the other two matches, with the engines unfortunately not able to consider their positions meanwhile.

KOMODO–ETHEREAL was on next. The drawfest continued with the exception of the fourth game in which KOMODO emerged three pawns to the good in the ending. The TCEC adjudication pre-empted an interesting demonstration of technique here. ‘LC0’ LEELA began confidently enough with a win as Black against ANDSCACS: it is as well that engines do not get discouraged. Two more draws followed: it is tough at the top, defences are strong and, though the odd result may go one way or the other, there is little to choose between these engines. ANDSCACS however was notably devoid of the EGT support that LC0 enjoyed. With the advantage of two connected passed pawns and a neat R-v-BN demonstration, LC0 won the ending of game 4: match-score 3-1. LC0 continued undefeated and even won the last game to return arguably the most impressive performance of the quarter-final. The HOUDINI-FIRE tiebreak finished the round with, surprisingly, a 0-1 win for HOUDINI after just two more games. In this way with some suspense, the top four seeds went forward to the semi-finals.

The semi-finals opened with a remarkable nineteen draws: eight by STOCKFISH–HOUDINI and three more after the eight by LC0–KOMODO. Has this ever happened before in computer chess? The deadlock was broken when HOUDINI took control of the open d-file on move 58, eventually lined up its Alekhine’s gun (Chessgames, 2019a/b) on move 80, cramped up Black’s position, created a passed-pawn with a neat tactic, and pushed that pawn to the seventh rank on move 100. STOCKFISH may have seen the advantage before HOUDINI but even so, it was too late to counter. With STOCKFISH a minor piece down, the ‘TCEC win’ adjudication followed quickly. Maybe not the biggest-shock result in TCEC history but certainly the biggest shock-result, especially given that HOUDINI had not been updated for some eighteen months. HOUDINI can beat STOCKFISH in a short match even if this is odds-against. ‘Kingscrusher’ (2019a) covered this game well on the day.

And so to the tiebreaker face-off between KOMODO and LEELA CHESS ZERO, the latter not an engine to rush its pleasures or its recognition of the TCEC deci-pawn ‘draw-zone’. This would be a tight match, KOMODO having beaten LC0 +1=5-0 in their recent head-to-head but LC0 was in a new version here, improving on even the LC0 that earned a place in the TCEC14 Superfinal. Sad that psychology does not play a part in computer chess. Eight draws took us into the second phase of the tiebreak, featuring Jeroen Noomen’s TCEC 9-13 Superfinal Opening book. This, by design, includes more volatile opening positions than other TCEC opening books, thus promoting a higher proportion of decisive games. Even so, LC0 surprisingly did the double immediately to qualify for the final. TCEC at this point introduced a bronze medal ‘small final’ between STOCKFISH and KOMODO which STOCKFISH duly won +2=5-1 sustaining only its second loss of the tournament. That game was the second half of a 1-0/1-0 pair so perhaps the opening handed too big a carrot to White. Apart from that game, KOMODO did not seem to build advantage.

The contest opened with seven draws and we pass quickly over to the game in which LC0 as White scored the decisive win. The evaluation, depth and EGT-support curves of Fig. 2 tell a tale. LC0 dramatically revised its expectations on finding 27. h5, Figs. 2 and 3a. Its situational awareness was clearly superior: it was significantly ahead of HOUDINI which only grew alarmed after 29. f4! and 32. … Nbd7, Fig. 3b: it was even ahead of the mega-threaded and 7-man-EGT-armed STOCKFISH, usually the leading prophet of doom. There is hope for humans yet: the audience had been saying for some time that the optics were at least dramatic – White with two bishops eyeing the black king’s h8-corner, relatively developed pieces and more freedom. LC0 was notably less dependent on depth of search as

the game went on and consulted the EGTs far less than HOUDINI did. After 35. Nxe5, Fig. 3c, LC0’s confidence increased again and after 39. … Rb8 as in Fig. 3d, remarkably the best option, HOUDINI was the exchange down and clearly in trouble at ‘-3’. With 54. Rb3 as in Fig. 3e, LC0 gave up a rook for a knight and converted pawn but by this time both engines knew the game was over. LEELA superfan ‘Kingscrusher’ (2019b) covers this game in detail, indicating some even less attractive byways for Black.

So, this special moment took on extra significance. An engine based on an artificial neural network and ‘MCTS’ Monte-Carlo Tree Searching had taken top step on a TCEC podium. Congratulations must go to Gian-Carlo Pascutto, Gary Linscott, Alexander Lyashuk (Chessdom, 2019) and the choir of angels ‘in the cloud’ who contributed to its self-play training.

A summary

Clearly, the Shannon (1950) mould, now over sixty years old, has been badly cracked if not completely broken. How this has been done is only semi-clear and even then, only to a few. Many will want to do their homework on the new paradigm, the ‘DCNN’ deep convolutional neural network architecture as exemplified by ALPHAZERO and LEELA CHESS ZERO. The ‘zero’ indicates that neither has been trained on human games but there is human input in the adoption of the DCNN approach and, of course, in the definition of the game domain and of what constitutes learning. We hope that further reading of the available sources (Sadler and Regan, 2019; Silver et al, 2017/18) will demystify the magic of these new machines.

Advised by Sadler (2018), what can we say about LEELA’s style of play? Compared to what we have seen before, it seems to be more strategic and less tactical, more interested in space and movement than in material, more interested in the prophylactic reduction of its opponent’s options. Questions remain about LEELA’s tactical ability where one would expect minimax to be more effective, where a narrow ‘study like’ path has to be found despite the presence of serious dangers.

MCTS has changed the game in several domains as evidenced by past articles in this journal and results at past ICGA Computer Olympiads. Was TD-GAMMON (Tesauro, 1995) the first demonstration of the new way? The combination of two concepts, MCTS and DCNN, has clearly been key: the future may combine further sets of ideas, e.g., MCTS and minimax-search. When should resources be shifted from one towards the other? We can expect to see new types of computer-chess engine in the future.

On a broader canvas, it appears that once again computer chess has been the Drosophila melanogaster fruit fly vehicle of choice for artificial intelligence research, showing the way forward for new kinds of analysis and insight. Improved early-detection in the medical field, driven by better computer vision, is a laudable priority with potential impact rivalling Hopkins’ invention of the fibrescope and his contribution to medical optics (Hopkins and Kapany, 1954/5; McCombie and Smith, 1998).

Wrapping up this report, we give the usual generic statistics on the defined openings and game-lengths, plus a selection of interesting endgames that arose, see Tables 6-8. Fuller data and the somewhat annotated pgn files of TCEC Cup 2 are available (Haworth and Hernandez, 2019c). Congratulations to the winning and unbeaten LEELA CHESS ZERO team (Linscott, 2018), also focusing on their TCEC14 Superfinal against STOCKFISH (Haworth and Hernandez, 2019d). Special thanks should also go to all the semi-finalists who produced such close matches: there is little between them. Once again, let us point out that this event would not be the same without the administrators’ efforts, the participation of the entire field of thirty-two engines and the audience in the ‘online lounge’ who contribute an enjoyable mix of questions and information, leavened by interspersed jokes and off-topic comments.

References
  • Chessdom (2019). https://tinyurl.com/icgaj048. Interview with Alexander Lyashuk, core member of the LEELA CHESS ZERO team.
  • Chessgames (2019a). https://tinyurl.com/icgaj041. The ‘Alekhine’s Gun’ game against Nimzovitsch.
  • Chessgames (2019b). https://tinyurl.com/icgaj052. Lagno–Wenjun, WWCC 2018, Alekhine’s Gun.
  • CPW (2019) https://tinyurl.com/icga046. Biographies of chess engines, authors and developers.
  • Haworth, G. McC. and Hernandez, N. (2019a). http://centaur.reading.ac.uk/80284/. TCEC Cup 1. This note plus annotated statistics and pgn files. Submitted to the ICGA Journal.
  • Haworth, G. McC. and Hernandez, N. (2019b). http://centaur.reading.ac.uk/78820/. TCEC13: the 13th Top Chess Engine Championship. Submitted to the ICGA Journal.
  • Haworth, G. McC. and Hernandez, N. (2019c). http://centaur.reading.ac.uk/81390/. TCEC Cup 2. This note plus annotated statistics and pgn files. Submitted to the ICGA Journal.
  • Haworth, G. McC. and Hernandez, N. (2019d). http://centaur.reading.ac.uk/82052/. TCEC14: the 14th Top Chess Engine Championship. To be submitted to the ICGA Journal.
  • Hopkins, H. H. and Kapany, N. S. (1954). A Flexible Fibrescope, using Static Scanning. Nature 173, 39-41.
  • Hopkins, H. H. and Kapany, N. S. (1955). Transparent Fibres for the Transmission of Optical Images. Optica Acta, 1(4), 164-170.
  • ‘Kingscrusher’ (2019a). http://tinyurl.com/icgaj039. HOUDINI-STOCKFISH, semi-final game 12.
  • ‘Kingscrusher’ (2019b). https://tinyurl.com/icgaj040. LC0-HOUDINI, final game 5.
  • Konoval, Y. (2019). Private communication of DTC(onversion) depths for some positions.
  • Linscott, G. (2018). https://github.com/LeelaChessZero/lc0/wiki LC0 on Github.
  • McCombie, C. W. and Smith, J. C. (1998). Harold Horace Hopkins. 6 December 1918 – 22 October 1994. Biographical Memoirs of Fellows of the Royal Society, 44, 239–252.
  • Sadler, M. (2018). https://tinyurl.com/icgaj045. Sadler on ALPHAZERO’s play.
  • Sadler, M. and Regan, N. (2019). Game Changer: AlphaZero’s Groundbreaking Chess Strategies and the Promise of AI. New in Chess. ISBN-13: 978-9056918187.
  • Shannon, C. E. (1950). Programming a Computer for Playing Chess. The London, Edinburgh and Dublin Philosophical Magazine, 41(314), 256-275. doi: 10.1080/14786445008521796.
  • Silver, D. et al (2017). Mastering Chess and Shogi by Self-Play with a General Reinforcement Learn-ing Algorithm. arXiv: 1712.01815.
  • Silver, D. et al (2018). A general reinforcement learning algorithm that masters chess, shogi, and Go through self-play. Science, 362(6419), 1140-1144. doi: 10.1126/science.aar6404.
  • Tesauro (1995). Temporal Difference
Full article

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Categories: Ενημέρωση

Interview with Alexander Lyashuk about the recent success of Lc0

Wed, 02/06/2019 - 14:51

Lc0 qualified for the Superfinal of the TCEC Championship and also won the TCEC Cup

The neural network chess engine Lc0 (aka Leela Chess Zero) is making the headlines with its performance in the Top Chess Engine Championship. First it qualified to the Superfinal of the competition by finishing second in the Premier Division, and a few weeks after it conquered its first major computer chess title by winning the TCEC Cup.

Live now: Follow the Superfinal of TCEC Stockfish vs Lc0

Chessdom spoke to one of the head admins and leading developers of the project Alexander Lyashuk about the history of the engine, its road in competitive chess, development details, and the future of computer chess in general.

 

Congratulations! Lc0 has finally conquered its first major title by winning the TCEC Cup

Indeed, a first major title for Lc0. That does feel really good, although I have to admit that this time it did not happen without some luck. :) Stockfish was eliminated before Leela had a chance to meet it, and that obviously helped a lot.

Anyway, it’s a great achievement for the team, and I’d like to mention that it’s not just the developers who made that progress possible. The main driver of the effort is actually the community, which contributes their computing power to help Leela learn, the people who do lots of strength testing, and the ones who run youtube videos and twitch streams, or just keep the morale up by being active in chat and forum.

Also, a big thanks to TCEC for providing a platform to showcase our progress and get the community excited about the Lc0 project. It’s indisputable that without TCEC Leela would be much less popular.

Lc0 is a very young project. It has been active for about an year. Is this the most meteoric rise to the top that computer chess has witnessed

There are two major dates which can be thought as a project start. The first one is Gary’s [Gary Linscott] official project announcement and start of a GitHub repository. That happened around 2-7 January 2018. Others think, that the actual start of the Leela training pipeline should be counted as the real start. That happened somewhere in the beginning of March 2018.

No matter which date we take as a start of the project, it is indeed probably the fastest rise of a chess engine. Although one can argue whether it’s a fair comparison in terms of developers achievement. Traditionally, developing a chess engine needed lots of chess expertise and trial and error. The developer has to fight with his bare hands for every 3 Elo points. If a developer takes a vacation, Elo growth stops. With Leela we of course do development and infrastructure maintenance work too, but all in all we just wait and Leela becomes stronger. We can go on a vacation, return in 1 week — and Leela magically learnt something new by itself.

Also, I’d like to remind that major part of Leela’s ideas come from DeepMind’s paper. Only recently we started to experiment with neural network architecture ideas which differ from what was written there. But all along the way, AlphaZero was the guide of our project.

Ed. note: Read about the entrance of Leela into competitive chess

The first time Lc0 appeared in a competition was in S12 of TCEC. Back then there was no GPU, it was just running on CPU. But that was also a time when the fanbase !boom began. Looking back at this moment, what are your thoughts?

It is good that TCEC now has GPUs. :) But back then I didn’t really expect TCEC to to make that serious investment in GPUs. For S13 I tried to urgently write a Leela backend to be able to parallelize work to 47 CPU cores, but then it was announced that the competition will have GPUs, so I could relax.

Yes, community growth really exploded with Leela entering TCEC, and we actually always have had a problem (a good problem to have!) that development couldn’t keep up with the number of contributors. It’s still kind of like this: there are lots of people contributing, there are lots of good ideas, too little time to implement.

Now from the look of history, what do you think about the technical difficulties experienced along the way?

That GPU overheating was a good source of burrito memes and jokes about poor Leela’s thermal management. :) Technical difficulties are unavoidable when you try something new. Maybe Leela didn’t show its real strength there, but it allowed her to play more games in the next season 14 (all the way through Div3).

More importantly, it led to changes in Leela’s time management, so now it’s more robust when run on stable hardware.

Currently Test30 net is triumphing. Test 40 is in developing and testing phase. Do you expect it to surpass Test 30? If yes, when? And how much ELO will that mean for Lc0?

Actually I didn’t have time to follow test 40 for the last 2 weeks, and 2 weeks for Leela is an eternity! But from other devs I heard a secret plan of keeping Leela play only draws in TCEC Cup for some weeks in order to delay TCEC Superfinal and send test 40 there. :)

So there is a hope that test 40 will take the lead soon.

A new paper was released by A0 recently, was it helpful in Lc0′s success this year?

It was really helpful as it filled in the remaining parts of a puzzle that we had. (Our findings are summarized here).

For some missing parts, we felt that there is something to be fixed, but didn’t dare to contradict the words of DeepMind’s pre-print. For example, we had an observation that Leela hardly ever changes the best move after 1 million nodes or so. There were different ideas to encourage more exploration as search goes, but in the end, it turned out that so-called “puct constant” was not a constant.

The Superfinal is coming. Lc0 has decisive games against every opponent this season except Stockfish. Is the Superfinal a chance to do that?

Beating Stockfish in S14 is not the most probable result, but it’s surely possible. I’m sure there will be interesting wins and maybe a bit of a drama as usual. It will be the most entertaining TCEC superfinal in recent years, and I hope lots of people will enjoy it.

And what what do you expect from Lc0 in S15?

If you search through our Discord server chat history, I did a prediction early in May there that Leela will win S15. I still hold this prediction. :)

Well, as a side note, I expected S15 to start around October 2018, so to be fair, I was a bit overly optimistic regarding the growth of Leela’s skills… Or maybe it’s vice versa, Leela noticed that there’s still a long time until S15 and relaxed. :)

Do you think the computer chess world is moving towards an era where the NNs will dominate over the AB engines?

First let’s clarify a terminology. There is a search algorithm (AB vs MCTS), and there is evaluation function (handwritten vs NN-based). Leela uses MCTS+NN, Stockfish uses AB+handwritten, but any combination is possible. For example, Komodo MCTS uses MCTS+handwritten, and Scorpio NN uses (as far as I heard) AB+NN.

I’m sure, that purely NN-driven chess engines will take over the Top-5 pretty soon. Currently the main drawback of NN-based evaluation function is it’s slowness compared to handwritten ones, but evaluation of neural networks will speed up and improve.

Classical engines with fast handwritten eval functions also don’t stay at one place though. Stockfish keeps the growth momentum really well, for example. It’s also nice to see that Leela also helps with that growth, providing ideas for Stockfish patches.

There was another NN engine participating this season – Scorpio NN. What do you think of the project of Daniel Shawul?

DeepMind’s publication demonstrated a new area to explore in chess engine world and I’m happy to see that another engine also picked that idea to try. I will be really curious to see its progress and wish it all the best in gaining ELO.

But I would also like to see other NN-based engines appear! Because to fill Top-5 with NN engines, we need at least 5 NN engines!

Categories: Ενημέρωση

Stockfish wins the Premier Division, Lc0 qualifies for the Superfinal

Mon, 02/04/2019 - 15:00

Stockfish, winner of the Premier Division of TCEC S14

The dominance of Stockfish in the Top Chess Engine Championship continues full steam ahead. The open source engine by Marco Costalba, Joona Kiiski, Gary Linscott and a huge community of contributors, won the Premier Division of Season 14 convincingly, not losing a single game along the way. With the victory Stockfish qualifies for the Superfinal, where it will be looking for a 4th consecutive and 6th overall TCEC title.

Stockfish wins TCEC S11
Stockfish wins TCEC S12
Stockfish wins TCEC S13

For the first time in history Stockfish will be in a situation where the “big 3″ of computer chess in not existent anymore. Lc0 aka Leela Chess Zero – the Neural Network built as an open source adaptation of DeepMind’s recent Alpha Zero artificial intelligence demonstration project – has broken the dominance the “big 3″ and has taken second position in the Premier Division ahead of Komodo (3rd) and Houdini (4th).

Live now: TCEC Superfinal at the official website

This is going to be the first match of Stockfish and Lc0 on the highest level of computer chess. The two could not meet in the recently concluded the TCEC Cup, due to a shocking loss of Stockfish to Houdini. In a mid-division test it was demonstrated that Lc0 is highly superior to Stockfish 8, mimicking the conditions and results of the SF8 – Alpha Zero match. However, Stockfish 10 is going to play the Superfinal, and it is much superior to the Stockfish 8 version, which makes the task for Lc0 exponentially more difficult.

This sentiment is shared among the computer chess fans. Out of the over 1000 (and counting) votes in the poll, 65% expect a Stockfish win in the Superfinal, while 35% expect Lc0 to be victorious. However, both Stockfish and Lc0 are going to line-up new versions compared to the TCEC Cup and anything can happen.

About the TCEC Superfinal

The Superfinal is a match between the winner of the Premier Division – Stockfish – and the second placed in the Premier Division – Lc0. It is a 100 games match, which is played with 50 different openings so that each engine plays both black and white of the same position. The match will be presented with opening 1 used in games 1 and 2, then opening 2 used in games 3 and 4 etc. If the match is theoretically won for one side before game 100, the match will still continue until all 100 games have been played. In the case of a drawn match there will be a rapid match of 16 games with a time control of 25′ + 10″ with random openings selected from earlier in the same Season. In case it is still tied there will be a Blitz match of 8 games with a time control of 3′ + 2″. When the Superfinal is over, the current Season ends. The winner is crowned the Grand Champion of TCEC.

Categories: Ενημέρωση

First major title for a Neural Network in chess: LC0 wins TCEC Cup

Mon, 02/04/2019 - 14:59

Neural Network chess fans around the world are celebrating as the first major computer chess title for the self-learning engine Lc0 (Leela Chess Zero) is a fact. Lc0 conquered the golden medal of the TCEC Cup in a 32 player knockout against the best engines in the world. The only NN playing in the competition emerged victorious after knocking out consecutively Tucano (8-0), Xiphos (6-2), Andscacs (5,5-2,5), the three time TCEC champion Komodo at the semi-final (10-8), and the three time TCEC champion Houdini at the final (4,5-3,5). Thus, Lc0 received the TCEC Cup gold medal, ahead of Houdini and the defending champion Stockfish.

Replay: Lc0 – Houdini , the decisive game

It seems that a knockout format with 30 min time control is the favorite of the world’s top NN engine. Lc0 won its first major medal in the same competition last year, while just three months later it is able to win the gold medal, going all the way undefeated.

Final standings (click on the image for full view)

Click on the image for full size view

Houdini – Stockfish (semi-final) by Kingscrusher

The match that forced Lc0 to play direct matches against all champions in TCEC history, analysed by Kingscrusher

First “end of an era” match?

Ever since Lc0 entered the Top Chess Engine Championship back in S12, the Neural Network believers were excited that an “end of an era” is coming. This expression originates in the fact that Stockfish has been dominating the computer chess world as the strongest AB chess engine, and that Leela as a Neural Network has the highest chance of changing the status quo.

Lc0 did not have a direct match against Stockfish in the TCEC Cup this year. However, it defeated in the final Houdini – a version that has won the TCEC Championship and that eliminated Stockfish at the semi-final. At its own semi-final Lc0 defeated another multiple times TCEC champion – Komodo – thus confirming that the second place in the Premier Division was a deserved one. This second place will finally give the chance to Lc0 to face Stockfish for the highest title of computer chess. It will happen at a 100 games long time control head-to-head match, the Superfinal of TCEC, that starts this February 4th at 15:00 CET.

The Superfinal is a chance for Lc0 to conquer yet another pinnacle. The TCEC Cup is the first time this TCEC season that LCZero did not lose a game – it did lose games in the lower Div3, Div2, and Div1. However, Lc0 has a win against every engine that it met this season. Except one – Stockfish.

Is the Superfinal going to be the “end of an era” or just another episode of a long lasting battle to come? Follow Stockfish – Lc0 Superfinal match live at the official website.

Categories: Ενημέρωση

TCEC Season 12 – the 12th Top Chess Engine Championship

Thu, 01/31/2019 - 15:02

Written by Guy Haworth and Nelson Hernandez
Reading, UK and Maryland, USA

This is the second in a new series of analytical articles on past TCEC events. The main text can be read below on this webpage, and at the bottom you will find a link to the full layouted article in pdf format, including the important tables, graphs and images.

TCEC is very grateful to the authors for their kind permission to publish these substantial and scholarly analyses of its events!

Introduction

After the successes of TCEC Season 11 (Haworth and Hernandez, 2018a), the Top Chess Engine Championship moved straight on to Season 12, starting April 18th 2018 with the same divisional structure if somewhat evolved.
Five divisions, each of eight engines, played two or more ‘DRR’ double round robin phases each, with promotions and relegations following. Classic tempi gradually lengthened and the Premier division’s top two engines played a 100-game match to determine the Grand Champion. The strategy for the selection of mandated openings was finessed from division to division. The revised TCEC engine line-up is illustrated and listed in Fig. 1 and Table 1.

Besides using FIDE’s 3x-repetition and 50-move drawing rules, TCEC terminated a game at move 40 or later if both engines had |eval| < 0.05 for ten consecutive plies in the current phase, i.e., since the last pawn-advance and/or capture. TCEC12 fell in line with most of the participating engines by adjudicating endgames using the Syzygy DTZ50″ EGTs rather than the Gaviota DTM EGTs which do not recognise the 50-move rule. 5-man EGTs were used for the divisions and 6-man EGTs were used for the Superfinal. Games which were apparently decisive were terminated by TCEC if both engines consistently agreed for the last eight plies that the evaluation is at least 6.5 or at most -6.5.
ELO ranged from 2714 to 3554, averaging 3143. Four new engines joined the fray this time:

  • LEELA CHESS ZERO, a new-architecture UCT/NN engine from a large community,
  • RODENT by the Polish chess programmer Pawel Koziol,
  • TUCANO by the Brazilian professional software developer/programmer Alcides Schulz, and
  • XIPHOS by the Serbian mathematician and computer scientist Milos Tatarevic.

The formidable 44-core server of TCEC11 was used unchanged in TCEC12.

Division 4, two DRR phases, 28 rounds, 112 games, tempo 30′+10″/m

A principal focus was the participation of the exciting LEELA CHESS ZERO, a neural-network-architecture engine inspired by the innovations of Deep Mind’s ALPHAZERO (Silver et al, 2017). The 14 most common two-move openings in the second author’s CATOBASE (Hernandez, 2018) were allocated to rounds 1-7 and 15-21, and with colours reversed for rounds 8-14 and 22-28, see Table 2.

The results, as played, are as in Table 3 though a rule introduced in TCEC11 required that the participation of SCORPIO be scratched as it had three technical crashes. The seven connection breaks with the server were thought to be caused by deadlock conditions in the engine. These losses in fact made no difference to the final ranking on this occasion. LC0 did not in fact progress but will be greatly helped by GPU assistance in a future season. The generic statistical review of TCEC12 results and terminations is given for each phase of TCEC12 in Table 11.

For division 4, all rounds have four games so game r.n is game 4r-4+n in the pgn files (Haworth and Hernandez, 2018b) and the colour-flipped pairings of engines are 28 games apart. This division had 10.8% of its wins below the diagonal of the eventual x-table. ETHEREAL alone was much improved, undefeated and a strong first while XIPHOS kept RODENT III in a distant third place, beating it 4-0.

Division 3, two DRR phases, 28 rounds, 112 games, tempo 30′+10″/m

In this division, the same fourteen openings were mandated as for Division 4 and used in the same order. This time however, the colour-reversed game followed immediately rather than 28 games later, giving an earlier balanced view on the bilateral contests. Rounds were therefore of eight games rather than four and were numbered from 1 to 14.

Draws under the 50-move rule are very rare in TCEC, less than 1% of terminations. This is because most engines seem to monitor the ply-count, zero their evaluations as they see it reaching 100, and allow TCEC draw-adjudication to take its course. Game 13.1/97, CHESSBRAINVB-WASP, was however a 50m-rule draw: CHESSBRAINVB retained hopes of a win to the end, despite being a pawn down.

CHESSBRAINVB was a clear winner but the race for the second promotion-spot was close. XIPHOS pulled off its second promotion this season, despite having lost its head-to-head matches with fellow candidates ETHEREAL and PEDONE. ETHEREAL more than justified its promotion to Division 3.

Division 2, two DRR phases, 28 rounds, 112 games, tempo 30′+10″/m

Fourteen of the most frequent 100 two-move openings in CATOBASE were allocated to rounds 1-14 with, again, the colour-reversed games being played immediately.

This time, FRITZ and TEXEL won promotion but the newly promoted XIPHOS and CHESSBRAINVB took the next two places. There were 10 technical crashes in the division, and both ARASAN and HANNIBAL were disqualified and relegated for disconnecting from the server: a pity as they had both scored wins against FRITZ. VAJOLET no doubt counted itself lucky to survive.

Division 1, two DRR phases, 28 rounds, 112 games, tempo 60′+10″/m

The normalised Sonneborn-Berger scores suggest that this was the most closely-contested division of TCEC12. Eventually, GINKGO and JONNY triumphed though FIZBO and BOOOT kept the result in doubt until almost the end. Thankfully, we did not see another rash of engine-disconnect fails, the one ultimately irrelevant incident being g8.8/64, FRITZ–JONNY. FRITZ as Black had beaten JONNY in their first, g1.7/7, encounter and hung on to its recent promotion: TEXEL did not.

Division P, four DRR phases, 56 rounds, 224 games, tempo 90′+10″/m

STOCKFISH was the only unbeaten engine but was still second with a Performance ELO of 3443, 121 down on its nominal 3554. KOMODO lost its eight-game match against STOCKFISH but had a better harvest of wins against the bottom three engines. HOUDINI made up the three engines that stretched away from the others. CHIRON crashed three times in the first round and was pulled from the event.

The TCEC12 Superfinal match: 100 games, tempo 120′+15″/m

The Superfinal between STOCKFISH and KOMODO surprised in two ways. First, it was not close and secondly, the win-rate was high. STOCKFISH won 29-9, 23/6 as White and 6/3 as Black so White also dominated Black 29-9. In terms of the fifty two-game pairs, STOCKFISH won 22 pairs 1½-½ and the g71-72 pair 2-0: KOMODO won 4 pairs 1½-½. GM Thechesspuzzler (2018) created a Youtube stream for the TCEC12 Superfinal. Wool (2018) provided some useful chessic insight on TCEC12 as a whole.

Summary

We gather together some generic statistics for the Divisions and Superfinal in Tables 11 and 12. These will help aficionados and analysts of computer chess to identify the particular games of interest to them later. The pgn files and further data are included with the e-repository version of this note (Haworth and Hernandez, 2018). Our congratulations go once again to the TCEC audience who made for a lively discussion forum, to all participants, particularly to those who gained promotion and to the TCEC12 Grand Champion, STOCKFISH and all its supporters.

REFERENCES
  • CPW (2018). https://tinyurl.com/icga046. Biographies of programs and authors.
  • de Man, R. (2018). http://tablebase.sesse.net/syzygy/. Site providing 5- and 6-man DTZ50 EGTs.
  • ‘GM Thechesspuzzler’ (2018). https://tinyurl.com/icgaj036. TCEC video playlists.
  • Haworth, G. McC. and Hernandez, N. (2018a). TCEC11: the 11th Top Chess Engine Championship. ICGA Journal 40(3). See also http://centaur.reading.ac.uk/75899/ for supporting data – results, statistics and pgn files.
  • Haworth, G. McC. and Hernandez, N. (2018b). http://centaur.reading.ac.uk/76985/. TCEC12: the 12th Top Chess Engine Championship. This article plus supporting data – results, statistics and pgn files.
  • Silver, D. et al (2017) https://arxiv.org/abs/1712.01815 Mastering Chess and Shogi by Self-Play with a General Reinforcement Learning Algorithm.
  • TCEC (2018) http://tcec.chessdom.com. Current and past TCEC tournaments.
  • Twitch (2018). https://www.twitch.tv/. A video/chat platform and community for gamers.
  • Wool, A. (2018) http://mytcecexperience.blogspot.co.uk/ TCEC blog.
Full article

To read the full article in pdf, click HERE

Categories: Ενημέρωση

Vladimir Kramnik ends his chess career

Tue, 01/29/2019 - 14:30

Former world champion Vladimir Kramnik (43) has just announced that he will end his career as a professional chess player. Kramnik was world champion from 2000 until 2007. He dethroned Garry Kasparov by beating him 8.5 – 6.5 in 2000. Kramnik didn’t lose a single game during this world championship match. He has won virtually all top tournaments, most notably ten clear of shared victories in Dortmund.

Kramnik: “I already decided to finish my professional chess career a couple of months ago and now, after having played my last tournament, I would like to announce it publicly.”

“The life of a professional chess player was a great journey and I am very thankful to chess for all it has given me. It has sometimes been difficult, sometimes more successful than I could ever imagine, but in any case it has been a priceless human experience for me. I have always tried my best to give it all from my side, being fully involved in it while working and playing chess.”

Vladimir Kramnik (photo by A.Karlovich)

“But I have also expressed in interviews before that I would like to try doing something else one day, and since my chess player motivation has dropped significantly in recent months, it feels like the right moment for it. I would like to concentrate on projects which I have been developing during the last months especially in the field of chess for children and education. I will soon provide more detailed information about those.”

Vladimir Kramnik developed a training program for the chess section of Sirius Educational Center in Sochi, the elite Russian establishment for talented children.

“I might still like to play a rapid or blitz chess tournament at times, or do a simultaneous like the Tata Steel Chess simultaneous in the Dutch parliament building this afternoon and will participate in various events connected with chess, popularising this great game.”

Jeroen van den Berg, director of the Tata Steel Chess Tournament: “I am honoured that Vladimir Kramnik has picked the Tata Steel Chess Tournament to be his last. I would have liked to see him to take leave with a better result, though. Vladimir is a great player. He is dynamic, all-round and a great fighter with a very keen insight. But above all he is a wonderful and warm person, with a great sense of humour. I will miss his presence in the top of the chess world, as will many chess aficionados all over the world. I wish him all the best with everything he is going to undertake and am sure our paths will cross again many more times.”

In the past weeks Kramnik participated in the Tata Steel Chess Tournament. This afternoon he will play the Tata Steel Chess simultaneous (Torentje Schaak) Tata Steel has organised for members of parliament and journalists in the parliament building in The Hague. This simultaneous is always the last event of the Tata Steel Chess Tournament.

Kramnik was recently appointed member of FIDE Planning and Development Commission (PDC).

Categories: Ενημέρωση

Pantsulaia emerges Chennai Open 2019 Champion

Mon, 01/28/2019 - 02:27

GM Pantsulaia Levan (Georgia) with 8.5 points emerged the Champion after the tenth and final round in the 11th Chennai Open International Grandmaster Chess tournament 2019 for Sakthi Group Dr N Mahalingam Trophy at Novotel IBIS OMR Hotel, Sholinganallur, Chennai on Friday 25th January, 2019.

In the crucial final round, Pantsulaia drew with top seed GM Predke Alexandr of Russia, moving to 8.5 points. The draw propelled the Georgian to clear first. This follows Pantsulaia’s title triumph at Delhi Open last fortnight, giving him back-to-back titles, a great start for 2019. The Georgian would take home the winner’s cheque of Rupees 300000 (Euros 3714) along with the handsome Sakthi Group Dr N Mahalingam Trophy.

Pantsulaia Levan (Georgia)

Sharing the second spot with 8.0 points were five Grandmasters viz., Popov Ivan (Russia), Aleksandrov Aleksej (Belarus), Paichadze Luka (Georgia), Megaranto Susanto (Indonesia) and Rozum Ivan (Russia). The top seeds had their say in the final round, as all the decisive games in the top ten boards went in favor of the higher rated player.

The Rupees 15 lakhs (Euros 18573) prize money tournament came to a glittering end, as the trophies and cash prizes were handed over to he winners’ by the Chief Guest India’s first International Master Manuel Aaron.

Present in the dais were Mr D V Sundar, Vice President, FIDE, Mr Stephen Balasamy P, Gen. Secretary, Tamil Nadu State Chess Association, International Arbiter R Anantharam, Mr B Murugavel, Vice President, Tamil Nadu State Chess Association and Chief Arbiter Manjunatha M.

Pantsulaia receiving the trophy from Chief Guest Manuel Aaron

Final Placings:
1. Pantsulaia Levan (Georgia) 8.5,
2-6. Popov Ivan (Russia), Aleksandrov Aleksej (Belarus), Paichadze Luka (Georgia), Megaranto Susanto (Indonesia), Ivan Rozum (Russia) 8.0,
7-14. Lugovskoy Maxim (Russia), Karthik Venkataraman (India), Predke Alexandr (Russia), Girish A Koushik, Vignesh N R (both India), Tran Tuan Minh (Vietnam), Czebe Attila (Hungary), Khusenkhojaev Muhammad (Tajikistan) 7.5 points (286 players)

R R Vasudevan
Press Officer
Chennai Open 2019

Categories: Ενημέρωση

Chennai Open: Akash among leaders, Harshavardhan stuns GM Rozum

Mon, 01/21/2019 - 17:39

Former National Champion International Master G Akash shared the lead with 4.0 points after the fourth round of the 11th Chennai Open International Grandmaster Chess tournament 2019 for Sakthi Group Dr N Mahalingam Trophy at Novotel IBIS OMR Hotel, Chennai here today.

GM Norm holder Akash scored over Grandmaster Ziatdinov Raset of USA. In the top board GM Paichadze Luka of Georgia scored over defending Champion, Grandmaster Laxman R R of India.

Sharing the lead at 4.0 points with Paichadze Luka (Georgia) were Tran Tuan Minh, Nguyen Van Huy (both Vietnam), Lugovskoy Maxim (Russia), Akash G, Karthik Venkataraman, Shyamnikhil P, Harikrishnan A Ra and Girish A Koushik (all India). Half a point behind at 3.5 points were 11 players including GMs Popov Ivan (Russia) and Aleksandrov Aleksej (Belarus) among others.

Top seeded Russian Grandmaster Alexandr Predke shed his second half a point, against Chennai based International Master T U Navin Kanna and remains at 3.0 points.

Top seed GM Alexandr Predke, P Stephen Balasamy, Gen Secy, TNSCA, B Murugavel, Vice President, TNSCA, GM Elect D Gukesh, D V Sundar, Vice President, FIDE, Frederic Friedel, Co-founder, ChessBase, IM Manuel Aaron

GM Norm holder Akash put it across GM Ziatdinov Raset of USA in a Ruy Lopez game that lasted 46 moves. An early exchange sacrifice showed the Indian’s will to go all out for win. Shattering both sides of the board, Akash kept the Ziatdinov’s king in the centre and finished the game in a flourish giving his rook thereby forcing the queening of his pawn.

Earlier, IM Norm holder G B Harshavardhan (Velammal School, Chennai) scored the biggest win of his career defeating third seeded Russian Grandmaster Rozum Ivan (ELO 2589) in the third round that concluded late yesterday. Rozum side stepped a draw by repetition on the 20th move, but went into an inferior rook ending that Chennai boy fully used to his advantage securing the win after 56 moves. Further, Harsha came up with a steady show today holding International Master N R Vignesh to a draw and is scheduled to meet Grandmaster Stupak Kirill (Belarus) in the next round.

IM Norm holder Harshavardhan G B

The third round also witnessed upset wins for Sai Vishwesh C and Senthil Maran K over Grandmasters Deviatkin Andrei and Sundararajan Kidambi respectively. Six rounds remain in this Rupees 15 lakhs (Euros 18460) prize money tournament that concludes on Friday, 25th January, 2019.

Earlier, the inauguration was preceded by a felicitation for the achievement of second youngest Grandmaster title in the history of chess by Chennai boy D Gukesh (DOB 29th May, 2006). Achieving the final GM Norm in the recently concluded Delhi Open, Gukesh, who is our current World Under 12 Champion, made it on his 12th year, 7th month and 17th day. The Velammal School boy fell short of world record holder Russian Sergey Karjakin by 17 days. Karjakin (DOB 12th Jan, 1990) had completed the GM title in 12 years and 7 months in 2002.

Mr S Kailasanathan, CEO, Microsense, GM Elect D Gukesh, International Master Manuel Aaron, Mr D V Sundar, Vice President, FIDE

Speaking on the felicitation of GM Elect Gukesh, Mr D V Sundar, Vice President FIDE said, “This boy, Gukesh, is bound to go far, bringing more laurels to himself and the country”.

Mr Frederic Friedel, Co-founder, ChessBase added, “Gukesh shows profound understanding for chess and I see the rising of another Magnus Carlsen in him”.

Mr S Kailasanathan, CEO of Microsense – official sponsor of Gukesh – added, “We could see the talent in Gukesh and were too happy to be of support to him during his great achievement”. M/s Microsense gave a cash award of Rs. 100000 (Rupees one lakh only) to the young achiever.

A cash award of Rs 30000 (Rupees thirty thousand only) was awarded to Master Gukesh on behalf of Tamil Nadu State Chess Association. Also present in the dais were, International Master Manuel Aaron, the Chief Guest, Shri P Stephen Balasamy, Gen. Secretary, TNSCA, Shri B Murugavel, Organising Secretary, Shri Rohan, General Manager, Novotel IBIS OMR Hotel, Shri V Hariharan, former Secretary AICF & TNSCA.

Manik Mikulas (Slovakia) playing Aleksandrov Aleksej (Belarus)

World Under 12 Girls Champion Savitha Shri B

Round 4 results (Indians unless specified) : Paichadze Luka (Geo) 4 bt Laxman R R (3), Manik Mikulas (Svk) 3.5 drew with Aleksandrov Aleksej (Blr) 3.5, Girish A Koushik (4) bt Deepan Chakkravarthy J (3), Stupak Kirill (Blr) 3.5 drew with Muthaiah A L (3.5), Rathanakaran K (3) lost to Tran Tuan Minh (Vie) 4, Tran Minh Thang (Vie) 3 lost to Karthik Venkataraman (4), Vignesh N R (3.5) drew with Harshavardhan G B (3.5), Akash G (4) bt Ziatdinov Raset (USA) 3, Sai Vishwesh C (3) lost to Nguyen Van Huy (Vie) 4

Round 3 results (Indians unless specified) : Pantsulaia Levan (Geo) 2 lost to Tran Minh Thang (Vie) 3, Harshavardhan G B (3) bt Rozum Ivan (Rus) 2, Popov Ivan (Rus) 2.5 drew with Saravanan V (2.5), Srihari L R (2) lost to Paichadze Luka (Geo) 3, Aleksandrov Aleksej (Blr) 3 bt Ameir Moheb (Egy) 2, Ziatdinov Raset (USA) 3 bt Erigaisi Arjun (2), Deepan Chakkravarthy J (3) bt Konguvel Ponnuswamy (2), Suvrajit Saha (2) lost to Stupak Kirill (Blr) 3

Round 2 Results (Indians unless specified) : Saranya J (1) lost to Pantsulaia Levan (Geo) 2, Rozum Ivan (Rus) 2 bt Rajarishi Karthi (1), Rathneesh R (1) lost to Popov Ivan (Rus) 2, Paichadze Luka (Geo) 2 bt Shiva Pavan Teja Sharma U (1), Bala Kannamma P (1) lost to Aleksandrov Aleksej (Blr) 2, Erigaisi Arjun (2) bt Md. Abzid Rahman (Bdesh) 1, Dahale Atul (1) lost to Deepan Chakkravarthy J (2).

Round 1 Results (Indians unless specified) Sathish Chandra G drew with Predke Alexandr (Rus), Pantsulaia Levan (Geo) bt Adireddy Tarun, Dharani Kumar M S lost to Rozum Ivan (Rus), Popov Ivan (Rus) bt Adarsh Tripathi, Evrin Selvam lost to Paichadze Luka (Geo), Aleksandro Aleksej (Blr) bt Aakash G, Badri Narayan B lost to Erigaisi Arjun, Deepan Chakkravarthy J bt Niharika Ch, Divyan T lost to Stupak Kirill (Blr), Tran Tuan Minh (Vie) bt Tejes Suresh Kumar, Giri Abhishek lost to Megaranto Susanto (Ina), Karthik Venkataraman bt Chirag Mudraje.

R R Vasudevan
Press Officer
Chennai Open 2019

Categories: Ενημέρωση

TCEC Cup 2 brackets and rules

Sat, 01/19/2019 - 14:51

The second edition of TCEC Cup, the minor trophy of the Top Chess Engine Championship, is going to start this January 21st. It will be a knockout competition involving the 32 world’s best chess engines. See the announcement article here.

TCEC Cup 2 consists of a total of 32 matches divided into sixteenth-final (aka round of 32), eighth-final, quarter-final, semi-final and final. For an engine to reach the TCEC Cup gold medal it must win a total of five matches. Both participants that lose the semi final will be awarded a bronze medal.

Brackets

Here are the brackets of the upcoming TCEC Cup 2:

Official brackets for TCEC Cup 2

Rules for TCEC Cup 2 Event

The TCEC Cup 2 is a knockout format played in TCEC, including all qualifying participants, seeded according to their respective final results in this season’s divisions. The 32 qualifying engines consist of the participants of Premier, 1st, 2nd and 3rd Division, plus the top 9 engines in 4th Division: because Deus X dropped out due to the uniqueness rule, the top 9 engines from Div4 are in the Cup this time (also three engines advanced from Div4 to Div3 this Season 14).

TCEC Cup knockout matches format

The TCEC Cup 2 will take place right after the Premier Division and before the Superfinal, starting on 21 January 2019. It will be a knockout championship with the 32 participants divided into brackets. Each participant will be seeded according to its final standing in the TCEC league event with the #1 seed meeting the #32 seed, #2 meeting #31, etc.

The TCEC Cup 2 will consist of a total of 32 matches divided into sixteenth-finals, eighth-finals, quarter-finals, semi-finals and final. For an engine to win the TCEC Cup gold medal it must win a total of five matches. The two losing semifinalists will play a match for 3rd and 4th place (`small final’).

Three openings books

All matches are played with a book exit from one of the three books in use: A, B or C. No bookless games will be played in the TCEC Cup.
Alternating match games will begin from a randomly selected starting position contained within an opening book created by Nelson Hernandez (aka Cato the Younger) with a large number of unique starting positions derived from human games. Engines will play both sides of each position selected. Openings chosen will roughly approximate human games in terms of their frequency. A new opening should thus occur every other game, then the reverse game is played, so two games in a row from the same starting book position. Because each engine will thus play both sides of every opening, fairness is guaranteed.

Two such books created by Nelson Hernandez will be used, one consisting of 2 move positions exclusively for the first round (sixteenth finals) hereafter referred to as BOOK A, and one consisting of 6 move positions (used from the eighth finals to the finals) hereafter referred to as BOOK B.
Furthermore a third book will be used in case tiebreaks do not lead to a decisive result within 16 games. This is an opening positions compilation by Nelson Hernandez with unique positions from the former Superfinal books TCEC Season 9-13, created by Jeroen Noomen for a higher level of decisiveness, hereafter referred to as BOOK C.

All three books will be used randomized.

Matches and tiebreaks

Each of the matches will at least consist of 4 pairs of games (8 games, every second with reversed colors and the same opening). These 8 games will always be played out in full, even if a decisive match result is reached before the full 8 games have been played.
In case of an equal score after these 8 games, tiebreakers will be played out at the end of the Cup round. First the 4 pairs of games will be played out for a round, before playing out the tiebreakers therefore.

Tiebreakers will be played according to the following rules:

  1. If a match is tied after its scheduled regular 8 games, pairs using the same book exit for both sides will be played until a decisive pair occurs. The book exits will be from the randomized book used in that phase of the CUP (A or B), up to a maximum of 4 pairs of games.
  2. If after playing in this way, no winner ensues, more pairs of games will be played, after each of which a match winner may ensue. From this point on, so from game 17 onwards, BOOK C will be used (the Superfinal book) with each playing both sides of the openings, for a maximum of 8 pairs of games, so a maximum of a further 16 games to decide a winner, with a new book.
  3. If even after these 32 games, a match is still drawn, further pairs of games will be played with BOOK C to determine a winner, but the time control (TC) will be shorter with each pair of games, according to the following steps (always indicated as minutes base time + seconds increment per move completed, so e.g. 30+5 means 30 minutes base time per game plus an increment of 5 seconds per move completed): 16+4, 8+3, 4+2, 2+1, 1+1. If even after this sequence of pairs of games with shorter TC the match is tied, the increment will remain at 1 second, but the base time will then become even shorter than one minute, in the following manner: 32s+1, 16s+1, 8s+1, 4s+1, 2s+1 and finally 1s+1 will be played until a decisive pair is reached.
Time control

Time control will be 30 mins + 5 secs increment per move for the normal games in a match, as well as for the tiebreakers up to and including game 32. If an engine loses on time, that result will not be changed nor the game replayed. If the TCEC game server locks up at any time during a game (BSOD, freeze etc), that game will be restarted unless the last position was a 6-man or less tablebase position, then it will be manually adjudicated. Whether a game is immediately restarted or played rather at the end of the round will be decided by the responsible TCEC staff.
As described in the section on tiebreaks, time control will change as of game 33 in tiebreakers.

Game adjudication

A game can be drawn by the normal 3-fold repetition rule or the 50-move rule. However, a game can also be drawn at move 35 or later if the eval from both playing engines are within +0.08 to -0.08 pawns for the last 5 moves, or 10 plies. If there is a pawn advance, or a capture of any kind, this special draw rule will reset and start over. In the website this rule is shown as “TCEC draw rule” with a number indicating how many plies there are left until it kicks in. It will adjudicate as won for one side if both playing engines have an eval of at least 10.0 pawns (or -10.00 in case of a black win) for 4 consecutive moves, or 8 plies – this rule is in effect as soon as the game starts. In the website this rule is shown as “TCEC win rule” with a number indicating how many plies there are left until it kicks in. Cutechess will also adjudicate 6-men or less endgame positions automatically with Syzygy tablebases.

Critical Engine Bugs

In the case of a serious, play-limiting bug (like crashing or interface communication problems, not including losses on time) not discovered during the pre-Cup testing, the engine might have the number of cores reduced, have the hash size reduced or have the tablebase access disabled – these changes will then remain for the rest of the Cup.

Engine Updates

Under no circumstances are updates to engines allowed once the Cup competition has started.

Engine Ratings

Because the TCEC Cup works with a different time control, TCEC ratings are not affected by the engines’ results in the Cup. A separate rating list may in time be created for this event and time control.

TD clause

In situations not covered by the rules, the tournament director decides.

TCEC Hardware

GPUs: (2): 1 x 2080 ti + 1 x 2080, CPU: Quad Core i5 3570k, RAM: 16gb DDR3-2133, SSD: Samsung 840 Pro 256gb, Battery backup: CP1350PFCLCD PFC Sinewave UPS System, Temperature: testing showed <=73C

CPUs: 44 Cores -> 2 x Intel Xeon E5 2699 v4 @ 2.8 GHz Motherboard: Supermicro X10DRL-i RAM: 64 GB DDR4 ECC SSD: Crucial CT250M500 240 GB Chassis: Supermicro OS: Windows Server 2012 R2

RAM: 15GB
SSD: 20GB + 165GB for TB

TCEC Cup starts 21 January 2019

Categories: Ενημέρωση

TCEC Cup 2 to start 17 January 2018

Sat, 01/12/2019 - 18:01

TCEC Cup is coming, with the top 32 engines in a knockout competition

The second edition of TCEC Cup, the minor trophy of the Top Chess Engine Championship, is going to start this January 17th. It will be a knockout competition involving the 32 world’s best chess engines.

TCEC Cup 2 consists of a total of 31 matches divided into sixteenth-final, eighth-final, quarter-final, semi-final and final. For an engine to reach the TCEC Cup gold medal it must win a total of five matches. Both participants that lose the semi final will be awarded a bronze medal.

Each of the matches will consist of 4 pairs of games (8 games, every second with reversed colors and the same opening) with time control 30 mins + 5 sec. In case of an equal score after these games, pairs of tiebreak games with the same time control will be held until a winner is determined.

Format and pairings

The first edition of TCEC Cup was played for the first time in 2018. It generated genuine hype and the refreshing new format was welcomed by the chess fans. As a result, the TCEC team has decided to maintain this knockout format competition and to make it a traditional one accompanying every season.

The winner of the TCEC Cup from last edition, Stockfish, will be the top seed in the knockout brackets. All the other engines will receive their pairing according to the final standings of the regular TCEC season. Awaiting the conclusion of the Premier Division (currently live, you can follow it here), the pairings for the first round of the upcoming TCEC Cup 2 are as follows:

Stockfish – Rodent
Tucano – 2nd place Div P
3rd place Div P – Demolito
Wasp – 4th place Div P
5th place Div P – Pirarucu
Schooner – 6th place Div P
7th place Div P – Hannibal
Nemorino – 8th place Div P

Fizbo – rofChade
Chiron – Pedone
Vajolet – Laser
Jonny – Arasan
Texel – Fritz
Ginkgo – Gull
ChessBrainVB – Xiphos
Booot – Nirvana

TCEC Cup 1 and TCEC Cup 2 differences

- TCEC Cup 1 pairings followed entirely the standings of the regular season. TCEC Cup 2, and subsequent cups, will have the winner of the previous Cup seeded as #1, while all the other participants will be seeded according to the regular season.

- Matches will once more consist of 8 games, however this time all 8 games of a given match will be played, even if an engine advances before game 8.

- Time control is changed from 30 min + 10 sec to 30 min + 5 sec , shortening the increment

Matches and tiebreaks

Each of the matches will consist of 4 pairs of games (8 games, every second with reversed colors and the same opening). In case of an equal score after these 8 games, pairs of tiebreak games with the same time control will be held until a winner is determined.

Time control

Time control will be 30 mins + 5 secs increment per move. If an engine loses on time, that result will not be changed nor the game replayed. If the TCEC game server locks up at any time during a game (BSOD, freeze etc), that game will be restarted unless the last position was a 6‐man or less tablebase position, in which case it will be manually adjudicated.

Openings books

Alternating match games will begin from a randomly selected starting position contained within special openings books by Nelson Hernandez (aka Cato the Younger). Engines will play both sides of each position selected. Openings chosen will roughly approximate human games in terms of their frequency. A new opening should thus occur every other game, then the reverse game is played, so two games in a row from the same starting book position. Because each engine will thus play both sides of every opening, fairness is guaranteed.

Round 1 will have all matches using a 2-move book, the rest of the rounds will use a 6-move book. These are chosen from a large openings book at random, ensuring reverse games to be played every next game. There will be no bookless games.

Game adjudication

A game can be drawn by the normal 3‐fold repetition rule or the 50‐move rule. However, a game can also be drawn at move 35 or later if the eval from both playing engines are within +0.08 to ‐0.08 pawns for the last 5 moves, or 10 plies. If there is a pawn advance, or a capture of any kind, this special draw rule will reset and start over. In the website this rule is shown as “TCEC draw rule” with a number indicating how many plies there are left until it kicks in. It will adjudicate as won for one side if both playing engines have an eval of at least 10.00 pawns (or ‐10.00 in case of a black win) for 5 consecutive moves, or 10 plies ‐ this rule is in effect as soon as the game starts. In the website this rule is shown as ”TCEC win rule” with a number indicating how many plies there are left until it kicks in. Cutechess will also adjudicate 6‐men or less endgame positions automatically with Syzygy tablebases.

Critical Engine Bugs

In the case of a serious, play‐limiting bug (like crashing or interface communication problems, not including losses on time) not discovered during the pre‐Cup testing, the engine might have the number of cores reduced, have the hash size reduced or have the tablebase access disabled ‐ these changes will then remain for the rest of the Cup.

Engine Updates

Engine authors can submit an updated version for the TCEC Cup. The deadline for submission is the last move of the Premier Division. Under no circumstances are updates to engines allowed once the Cup competition has started.

Categories: Ενημέρωση

FIDE bank account in Spanish Caixa Bank

Fri, 01/11/2019 - 12:40

In a brief post FIDE announced that a bank account is opened with Caixa Bank, one of the largest banks in Spain.

The normal operation is resumed 11 months after the Swiss bank UBS closed the FIDE accounts due to then FIDE President Kirsan Ilyumzhinov being on the US sanctions list. Kirsan Ilyumzhinov refused to resign from the post to save FIDE the trouble, and even announced he would be running for re-election, famously with a fake American person on the ticket.

After Chessdom.com revealed the scandal, the Russian government introduced a new candidate Arkady Dvorkovich, who eventually became FIDE President. The bank account is opened three months after his election.

Categories: Ενημέρωση

Tata Steel 2019

Thu, 01/10/2019 - 08:39

Tata Steel Chess 2019 is going to take place 11 – 27 January in Wijk aan Zee. The traditional tournament is going to feature once more two groups of 14 players.

The Tata Steel Chess Tournament is one of the most prestigious events in the international chess calendar. Often refered to as the “Wimbledon of Chess”, Tata Steel Chess Tournament celebrates its 81st year.

Group A consists of the World Champion Magnus Carlsen, Shakhriyar Mameedyarov, Ding Liren, Anish Giri, Vladimir Kramnik, Viswanathan Anand, Ian Nepomniachtchi, Teimour Radjabov, Jan-Krzysztof Duda, Richard Rapport, Samuel Shankland, Vladimir Fedoseev, Vidit Santosh Gujrathi, and Jordan Van Foreest. The average ELO of the group is 2753, which makes it a category 21 event.

Live games with analysis Tata Chess 2019 Masters

The Challengers group consists of Anton Korobov, Parham Maghsoodloo, Vladislav Kovalev, Evgeny Bareev, Erwin L’Ami, Benjamin Gledura, Maxim Chigaev, Andrey Esipenko, R Praggnanandhaa, Vincent Keymer, Lucas Van Foreest, Elizabeth Paehtz, Dinara Sadukassova, and Stefan Kuipers. The average ELO of the Challengers is 2582 and the category of the tournament 14.

Live games with analysis Tata Chess 2019 Challengers

 

Tata Steel 2019 official website players presentation

 

Magnus Carlsen

Magnus Carlsen will play his 15th Tata Steel Chess Tournament in 2019. It proves the special bond between the World Champion and his favourite tournament, where he started his impressive career in 2004, winning with the fantastic score of 10,5 – 13 at the age of 13 in the former Grandmastergroup C of our tournament. He has won all three events in Wijk aan Zee (A-, B- and C-group) and since 2018 he is the sole record holder. In our 80th tournament the then both record holders participated (Carlsen and Anand), but it was Carlsen who won in 2018, after a thrilling tiebreak against Anish Giri (1,5-0,5 for Magnus). It will be interesting to see how Magnus did recover from his tensed WC-match against Fabiano Caruana in London (November 2018), which he won – as against Anish – after a tiebreak (3-0). Will we see him winning the Tata Steel Chess Tournament for the 7th time?

Country: Norway

Photo: Alina l’Ami Shakriyar Mamadyarov

2017 was the year of Shakhriyar Mamedyarov. At the start of that year, Mamedyarov was ranked 13th on the FIDE Rating listand exactly one year later we found him back on the third place, with just behind Carlsen and Caruana. It has happened more than once that players have difficulties maintaining such a high position, but not so for Shakh! On the contrary, he kept on playing very well in 2018 with a highlight in Biel, where he won the traditional tournament with the impressive score of 7,5-11. He ended 1,5 points ahead of Nr. 2 Magnus Carlsen, whom he beat 1,5-0,5 in their mutual encounter. The two times World Junior Champion will play for the 5th time in the Masters. His best result in Wijk aan Zee was in 2018, when he shared 3rd place with Vladimir Kramnik. With his attacking style and huge self-confidence he is definitely one of the favourites again in the 81st  edition. The secret of his run to the top? ‘A more stable life’, Shakh said in an interview. He got married in 2017 and became a father in 2018.

Country: Azerbaijan

Photo: Alina l’Ami Ding Liren

Chinese Top-player Ding Liren comes back to Wijk aan Zee after a short absence of two years. It will be his 3rd appearance in Wijk aan Zee. Ding played his last Tata Steel Chess Tournament in 2016, finishing shared second with Fabiano Caruana. Both of them had 8 points, finishing 1 point behind winner Magnus Carlsen.  In his first Tata Steel Chess Tournament, one year earlier, Ding also shared second place, together with Giri, Vachier-Lagrave and So. Remarkable was the way he built up his score then: 7 wins, 3 losses and 3 draws.

The three times Chinese champion, ranked no. 4 in the world, made a remarkable record in 2017 and 2018: he stayed undefeated in 100 games (29 victories and 71 draws) on the highest level. Ding has more records: he is the highest ranked player from China ever, and also the first Chinese player to have broken the barrier of 2800-rating, meaning a place among the absolute elite-players.

It is obvious that Ding Liren, with his uncompromised style of play, is one of the top-favourites in the 81st Tata Steel Masters. Winning this year’s tournament will automatically lead to a new record, since no Chinese player has won the Tata Steel Masters before.

Country: China

Photo: New in Chess Anish Giri

Young Dutch superstar Anish Giri came to Holland in his early teens, and mastered the language fluently in no time. The Tata Steel Chess Ambassador led a ‘normal life’ in high school, not far away from his hometown Rijswijk, where he used to live with his parents. Meanwhile he managed to become a top grandmaster, which proves his huge talent and intelligence. After having finished his school, Giri became a professional. Wijk aan Zee has no secrets for Anish. He will play for the 11th time in a row in our tournament, having participated in all three groups (A, B and C). Since 2011 Anish has played in the Masters, with three second places and one fourth place as his best achievements so far. Actually his best result ever was last year, when he shared first place with no one less than Magnus Carlsen. Only after the tiebreak (1,5-0,5 in favour of Carlsen), Giri had to accept that he became second in the tournament. Giri  is still known as one of World’s best prepared opening players, while he is also known as practically unbeatable. After 2016 and 2017 did not bring him the successes he was hoping for, the 80th Tata Steel Chess Tournament was a kind of turning point, because in 2018 his results were just great. It brought Giri back in the World Top-5.

Country: Netherlands

Photo: Alina ‘Ami Vladimir Kramnik

Before last year, it had been quite a while since ‘Big Vlad’ played in our tournament: 2011 was the last time, before he came back to Wijk aan Zee in 2018. It will be his 13th appearance. His first tournament was in 1998, where he shared first place with his friend and rival Viswanathan Anand. It has been his only tournament victory so far. It is always a pleasure to have Kramnik around, so we are glad that he accepted the invitation to come back in 2019! The former World Champion (2000 – 2007) is still very active as a player, despite the fact that the now 43 years old once ‘threatened’ to quit chess at the age of 40… Kramnik is still difficult to beat, all his opponents respect him a lot, also the ones from the new generation. Obviously he has lots of fun playing chess nowadays. His games are always full of energy and he produces lots of fighting chess, which is great news for his huge number of chess fans. Kramnik shared 3rd place in 2018, with the fantastic score of six wins, two losses and only five draws. When in the same form, Vladimir is automatically top candidate again to fight for first place in 2019!

Country: Russia

Photo: Alina l’Ami Viswanathan Anand

The great Vishy Anand already played 18 times in Wijk aan Zee, including his Candidates match against Arthur Jusupov in 1994. Anand made his debut in 1989, the period when his nickname was still ‘Speedy Gonzales’, as it was his habit the to think between 30 and 60 minutes about an entire game. It proved his exceptional talent for the game. Anand had just turned 19 then when he shared first place in our tournament with Sax, Ribli and Nikolic at his first appearance in Wijk aan Zee. Later, Anand won again in 1998, 2003, 2004 and 2006. Together with Carlsen he was record holder till the year 2018, winning the Tata Steel Chess Tournament 5 times. In 2018 though, it was Carlsen who won his 6tht Tata Steel Chess Tournament, making the Norwegian World Champion the sole record holder now. Vishy himself however, also made 6 second places and 3  third places. So Wijk aan Zee and Viswanathan Anand go together quite well! Not only in results; Vishy has said more than once that he likes the particular atmosphere in the coastal village. In 2018 Anand shared 5th place with Wesley So.

Of course there is more than Wijk aan Zee on his record list: the tiger from Madras (now Chennai) was World Champion, Junior World Champion and he won practically all important tournaments  all over the world (Tilburg, Linares, Madrid, Monaco, Dortmund, Mainz, Leon…. only to name a few…). As it is for legends as Kasparov, Fischer and Karpov it is also not easy to write a small biography about Anand, because his list with successes is simply too long to name them all. It is our pleasure that the modest chess giant from India is back in Wijk aan Zee, now for the second year in a row, after a few years of absence before 2018.

Country: India

Photo: Alina l’Ami Ian Nepomniachtchi

The super GM from Russia, Ian Nepomniachtchi, has a particular record in his hands: he is the only top player who never lost a game to his friend and rival Magnus Carlsen in classical chess. He defeated Carlsen already four times, while they drew four times as well. Both players already met when they were very young, being born in the same year (1990). ‘Nepo’ was ranked in the top-5 in both Rapid and Blitz, but in Classical Chess he never made it into the top-10 though. The 11th place in January 2017 was his highest position ever.

‘Nepo’  won several strong tournaments, which proves that he should be capable of getting into the top-10. His aggressive style brings certain risks, which leads to minor results from time to time as well. See for instance the last Tata Steel Chess Tournament he played: in 2017, after a superb year in  2016, ‘Nepo’ did not come further that a score of 5 – 13, finishing 12th. Will he now finish in the first half of the final ranking list? It should be possible, we all know this!

Country: Russia

Photo: New in Chess Teimour Radjabov

31-year old Teimour Radjabov is a former chess prodigy. He was already quite strong at a very young age, in a period when this was less customary than nowadays. Radjabov gained the GM-title in 2001, at the age of 14. Radjabov has a long and impressive list with tournament victories, among others the shared 1st place in Wijk aan Zee 2007, together with Levon Aronian and Veselin Topalov. Radjabov, who will play his 7th Tata Steel Masters, is known for his solid style and it is very difficult to beat him. He knows a lot about opening theory and at the highest level he still is a fan of the Kings-Indian, a sharp opening that used to be popular but somehow lost its popularity during the last years. Radjabov is less active since he got married and became a father, but still he is a world class player, which is proved by his current position on the world ranking list (14th). We are happy that Teimour comes back to Wijk aan Zee, the village where he gained his first international  successes as a young boy!

Photo: New in Chess

Country: Azerbaijan Jan-Krzysztof Duda

Reading all 14 portraits of the 2019-edition of the Tata Steel Masters, will lead to a high number of the word ‘prodigy’. As many others in this group, Duda gained the Grandmaster title at an early age: 15 years and 21 days. The reigning Polish Champion has already an impressive list with career highlights, a.o. the shared 1st place in the Junior World Championship in 2015, taking silver behind winner Antipov on tiebreak.

2018 became Duda’s year of his international breakthrough.  Besides winning the strong national championship (before Wojtaszek) he finished 4th in Dortmund and performed very well at the Chess Olympiad in Batumi, where he drew on first board against the elite players Levon Aronian, Viswanathan Anand, Fabiano Caruana, Shakhriyar Mamedyarov and Sergey Karjakin. In 2014 Duda finished with 7-13 in the Challengers, his only Tata Steel Chess appearance so far. It is now time to see him perform at the highest level in Wijk aan Zee! In the World Championship Blitz in St. Petersburg (29 and 30 December 2018) Duda proved that he is ready, finishing second behind winner Magnus Carlsen with an incredible score of 16,5-21, which would normally would be enough for victory, but Carlsen is – of course – Carlsen and he won with 17-21.

Country: Poland

Photo: New in Chess Richard Rapport

Richard Rapport is one of the many chess prodigy’s in the world of chess. The now 22 years old Rapport became Grandmaster at the age of 13 years, 11 months and 6 days. He started to play chess at the age of four.

Richard is not only known for his huge talent for the game, but perhaps even more for his approach: he is considered as one of the most original top players of his time. When Tournament Director Jeroen van den Berg told the news on his local club in Amsterdam that Rapport was the 14th player in the Tata Steel Masters, most of the members reacted incredibly happy. It proves how many fans Richard has, all over the world and not only in Hungary, where he was national champion in 2017.

It will be Rapport’s 4th appearance in Wijk aan Zee. In 2013 he was co-winner of the Challengers, while in 2014 and 2017 he finished in the bottom part in the Masters. It is clear that Rapport wants to prove that he can not only play originally, but also make points with his style. And we all know he can, since he beat no one less that Magnus Carlsen in their first encounter in 2017, in Wijk aan Zee!

Country: Hungary

Photo: New in Chess Sam Shankland

27-year old Sam Shankland had a great year in 2018. Especially in the first part it seemed that everything he touched, turned into gold. He won three tournaments in a row: the Us Championship, the Capablanca Memorial and the American Continental Chess Championship. In all three events he stayed undefeated and with these results he broke the 2700-rating barrier for the first time in his life. It also brought him to the best 30 players in the world.

For the current US Champion (which title he won ahead of the top Americans Caruana, So and Nakamura!) it will be his first appearance in an elite tournament. Shankland has a aggressive style of play, it will be interesting to see how he will perform against the best players in the world. Or, as he tweeted himself in November: “Excited to be playing with the big boys!”

It is not his first appearance in Wijk aan Zee. Shankland played in the Tata Steel Challengers in 2015, finishing 3rd behind Wei Yi (1) and Navara (2), with a score of 9 – 13. Shankland stayed undefeated in that event as well.

Country: USA

Photo: New in Chess

  Vladimir Fedoseev

23-year old Vladimir Fedoseev  is the only ‘real debutant’ in this year’s edition of the Tata Steel Masters. Where other newcomers in the Masters played earlier in the Challengers, Fedoseev never played in Wijk aan Zee before. The Super GM from Saint Petersburg booked some remarkable results in 2017, such as winning the Aeroflot Open, the second place in the Sparkassen Chess-Meeting in Dortmund, shared 1st place in the European Championship but finishing 3rd on tiebreak, 3rd place in the Russian Championship and runner-up in the  World Rapid Chess Championship in Riyadh, after losing the play-off to Anand. With all these results Fedoseev climbed up to the Top-30 of the FIDE-World Ranking List. In 2018 his results were more or less consistent, so that he maintained his high position. It is now time to see this original and creative player in Wijk aan Zee!

Fedoseev is known for his ambition to win every game, either with White or Black. This makes him a very attractive player for any tournament. It is interesting to see what result Fedoseev will reach with his optimistic style in an elite Tournament with 13 rounds. That he will play some creative games and cause some surprising results,  is likely to be a fact!

Photo: New in Chess

Country: Russia Vidit Gujrathi

Vidit is one of the many young talents from India. The 24 year old GM already was in Wijk aan Zee for the first time in 2017, being the second of Anish Giri. One year later he played in the Challengers, which group he won with 9 points out of 13 and one point ahead of Anton Korobov from Ukraine. It gave him the right to play in  the Masters of this year. Vidit is one of the five young debutants. With his dynamic style and great knowledge of the game, plus his self-confidence, it is obvious that he is ready for his first elite tournament. However, as for all debutants, playing on this level with 13 rounds to come, is not an easy task. It will be interesting to see how the open minded youngster from Nasik will perform this year. Vidit is the number-3 ranked player in India, after Anand and Harikrishna.

Country: India

Photo: Alina l’Ami Jorden van Foreest

Jorden van Foreest will make his 4th consecutive appearance in the Tata Steel Chess Tournament. And still he is only 19 years old! Jorden played very well in his first Tata Steel Chess Tournament in 2016, scoring 50% with only three draws, which is typical for his fighting spirit, but the year 2017 was a disappointment (4 points) for him. In 2018 Jorden played his best Challengers Tournament so far, finishing shared 3rd with a score of 7,5 – 13. One of his highlights in his career is winning the Dutch Championship in 2016, at the age of 17. But he also won the individual European Championship Under-14 in 2013. At the age of 16 he became international Grandmaster. According to a long tradition in Wijk aan Zee, such strong, young Dutch Grandmasters will automatically get a chance to compete with the strongest players in the world, meaning a place in the Masters. Now it is time for Jorden! It will be a tough test for Jorden, but he is at least certain that 17.000.000 people will root for him!

Country: The Netherlands

Photo: Alina l’Ami

Categories: Ενημέρωση

Tata Steel Chess 2019 LIVE!

Thu, 01/10/2019 - 08:37

Tata Steel Chess 2019 is going to take place 11 – 27 January in Wijk aan Zee. The traditional tournament is going to feature once more two groups of 14 players.

The Tata Steel Chess Tournament is one of the most prestigious events in the international chess calendar. Often refered to as the “Wimbledon of Chess”, Tata Steel Chess Tournament celebrates its 81st year.

Group A consists of the World Champion Magnus Carlsen, Shakhriyar Mameedyarov, Ding Liren, Anish Giri, Vladimir Kramnik, Viswanathan Anand, Ian Nepomniachtchi, Teimour Radjabov, Jan-Krzysztof Duda, Richard Rapport, Samuel Shankland, Vladimir Fedoseev, Vidit Santosh Gujrathi, and Jordan Van Foreest. The average ELO of the group is 2753, which makes it a category 21 event.

Live games will be daily on Chessdom with analysis by Komodo, Houdini, and Stockfish. Games start at 13:30 CET.

More live: TCEC Premier Division

Watch live video from TCEC_Chess_TV on www.twitch.tv

Categories: Ενημέρωση

Open de Portugal 2019

Thu, 01/10/2019 - 00:00

The Portuguese Chess Federation will hold the Portugal Open from 2-10th February 2019 at the Pavilhão Casal Vistoso in Lisbon.

The tournament will be a 9-round Swiss system, rated for FIDE, and valid for title norms. The tournament is included in the national Classical Chess Circuit.

On 10 February, there will be an (optional) rapid tournament, included in the national Rapid Chess Circuit.

Top prizes are 2500€ / 1600€ / 1000€ / 800€ / 700€ / 600€ / 500€ etc

Currently 132 players from 32 federations are registered to take part in the event. Among them are 15 Grandmasters and 14 International Masters.

Official website

Participants:

1. GM Motylev Alexander RUS 2644
2. GM Iturrizaga Bonelli Eduardo VEN 2637
3. GM Petrov Nikita RUS 2585
4. GM Xu Xiangyu CHN 2567
5. GM David Alberto ITA 2559
6. GM Bernadskiy Vitaliy UKR 2550
7. GM Jakubowski Krzysztof POL 2516
8. GM Stefansson Hannes ISL 2514
9. GM Spraggett Kevin Barry CAN 2513
10. GM Galego Luis POR 2508
11. IM Bilguun Sumiya MGL 2471
12. GM Miezis Normunds LAT 2469
13. IM Iniyan P IND 2456
14. IM Butkiewicz Lukasz POL 2444
15. IM Damaso Rui POR 2438
16. FM Srinath Rao Sankrantipati Venkata IND 2433
17. Mu Ke CHN 2431
18. WGM Ni Shiqun CHN 2427
19. GM Thorhallsson Throstur ISL 2425
20. GM Campora Daniel ARG 2417
21. IM Rajesh V A V IND 2410
22. IM Kaasen Tor Fredrik NOR 2409
23. FM Haug Johannes NOR 2402
24. IM Sukandar Irine Kharisma INA 2397
25. IM Low Zhen Yu Cyrus SGP 2385
26. IM Carrasco Martinez Juan M. ESP 2380
27. IM Miedema David NED 2370
28. FM Martin Duque Jesus ESP 2365
29. IM Rocha Sergio POR 2360
30. FM Aguera Naredo Javier ESP 2345
31. FM Tryggestad Andreas Garberg NOR 2333
32. IM Sergienko Sergey RUS 2331
33. FM Pantzar Milton SWE 2331
34. WGM Gu Xiaobing CHN 2326
35. Fus Jakub POL 2326
36. FM Godzwon Iwo POL 2323
37. FM Kowalski Igor POL 2312
38. IM Ilic Zoran S SRB 2302
39. Chinguun Sumiya MGL 2286
40. FM Risting Eivind Olav NOR 2281
41. FM Pacan-Milej Kosma POL 2273
42. FM Storme Isak SWE 2271
43. FM Chylewski Patryk POL 2268
44. WFM Li Yunshan CHN 2246
45. FM Nordquelle Daniel NOR 2235
46. CM Garcia Dorado Alberto ESP 2235
47. FM Ranaldi Lucas NOR 2230
48. FM Rego Pedro POR 2228
49. FM Nielsen Andre NOR 2211
50. Lindbol Aleksander NOR 2204
51. Costa Paulo Jorge Lopes POR 2200
52. FM Ermeni Avni KOS 2194
53. Li Xueyi CHN 2194
54. Tscharotschkin Michael GER 2178
55. NM Paiva Henrique POR 2174
56. Borges Guilherme Deola BRA 2171
57. WIM Newrkla Katharina AUT 2162
58. Lisowski Krzysztof POL 2135
59. FM Pascoal Eduardo A ANG 2132
60. Pirola Claudionor Alcides Lima BRA 2130
61. Dias Ricardo Pedro Cruz POR 2128
62. Bruaset Eivind NOR 2124
63. WFM Cholleti Sahajasri IND 2122
64. FM Thompson Ian D ENG 2121
65. Bub Volker GER 2108
66. Hodovsky Jiri CZE 2106
67. WFM Froewis Annika AUT 2100
68. Barbier Wim BEL 2086
69. Fernandez Montero Francisco M. ESP 2070
70. Golecki Jan POL 2064
71. Fernandez Vallejo Luis ESP 2063
72. Huse Sigurd Kjelsbol NOR 2060
73. Romano Joao Manuel Pereira POR 2055
74. Soares Luis F Almeida M Sousa POR 2036
75. Fernandes Ricardo Paulos POR 2020
76. Kocian Miroslav CZE 2013
77. Slovak Pavel CZE 2007
78. Cavaleiro Daniel Filipe Costa POR 2000
79. Thibault Pierre-Olivier FRA 1994
80. Myrheim Hakon Abeland NOR 1993
81. WFM Skogvall Martina GER 1992
82. Rionda Medio Angel Arturo ESP 1992
83. Rogers Tim L ENG 1981
84. Bouton Christophe FRA 1964
85. Archambault Serge CAN 1959
86. Fossan Aleksander NOR 1949
87. Barbier Astrid BEL 1945
88. Roque Armando Filipe Da Silva POR 1941
89. Woithe Daniel GER 1908
90. Damasceno Jorge Manuel Cardos POR 1895
91. Marques Rui Filipe Pereira POR 1890
92. Sandhya Goli IND 1890
93. Nikula Mikko FIN 1889
94. Morejko Wojciech GER 1879
95. Marcos Herrero Francisco ESP 1855
96. Jarve Edvin NOR 1829
97. Nass Sara NOR 1822
98. Aguiar Carlos Alberto Branco POR 1817
99. Taylor Robert Graham WLS 1809
100. Elias Ruben Joel Monteiro POR 1797
101. Iasman Inna FRA 1794
102. Skjolingstad Sverre NOR 1782
103. Sa Nuno Baltazar POR 1767
104. Le Gall Eric FRA 1758
105. Calzada Cruz Osvaldo CUB 1754
106. Hestvik Elias NOR 1740
107. Haisma Henk NED 1727
108. Avelino Camila Biscaya POR 1689
109. Haynes Noah NOR 1658
110. Goncalves Carlos M Marques POR 1639
111. Almeida Rui Pedro Albergaria POR 1583
112. Marques Gilles FRA 1581
113. Cavadas Jose Manuel Goncalves POR 1577
114. Oliveira Fernando Alves POR 1575
115. Dias Jose De Oliveira Gaspar POR 1560
116. Gaudin Bruno FRA 1558
117. Antunes Andre Rafael Maissa POR 1521
118. Almeida Jose Antonio Ferreira POR 1507
119. Florissi Aldo ITA 1502
120. Dong Fabio Yingfan POR 1493
121. Funk Guenther Matthias Andrea POR 1492
122. Correia Pedro Mourao Soares POR 1472
123. Reis Angelica Mufato BRA 1465
124. Voges Guilherme Lopes Jesus POR 1458
125. Machado Carlos Augusto POR 1415
126. Dong Rafael Yufan POR 1377
127. Paragliola Gennaro ITA 1367
128. Fonseca Rene Gil Bakker POR 1355
129. Maissa Susana Flora Cesana POR 1302
130. Anfinsen Marius NOR 1113
131. Ferreira Cristina Isabel POR 1011
132. Wang Cong CHN 0

Categories: Ενημέρωση

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