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101-534: Double Wing Attack, which has been played since the Edo period, has been known as a strategy prone to fierce battles due to the lack of a well-developed joseki . However, with the development of computer shogi in the late 2010s including programs such as AlphaZero adopting Double Attack, there has been further progress in the josekis for this opening, which has led to its adoption in most professional title games in 2021 highlighting its importance. The Double Wing Attack

202-472: A Side Pawn Capture opening (where the pawn on 34 or 76 are captured by a rook) instead an open bishop diagonal variation of Double Wing. This a major change from past centuries where Side Pawn Capture openings were uncommon as they were considered to be inferior strategies. In the second half of the 20th century, Side Pawn Capture was recognized as a sound opening – eventually becoming one of the most popular Double Static Rook opening among professional players in

303-447: A "blunder" rather than a normal mistake is somewhat subjective. A weak move from a novice player might be explained by the player's lack of skill, while the same move from a master might be called a blunder. In chess annotation , blunders are typically marked with a double question mark ("??") after the move. Especially among amateur and novice players, blunders often occur because of a faulty thought process where players do not consider

404-498: A Bishop handicap . In 2012, a retired professional lost a match with computer publicly first, and in 2013, active shogi professionals too. The Japan Shogi Association (JSA) gave reigning Ryuo Champion Watanabe permission to compete against the reigning World Computer Shogi Champion Bonanza on 21 March 2007. Daiwa Securities sponsored the match. Hoki Kunihito wrote Bonanza. The computer was an Intel Xeon 2.66 GHz 8 core with 8 gigabytes of memory and 160-gigabyte hard drive. The game

505-474: A Japan Shogi Association professional 5 dan played shogi against a computer. The game was played at the 29th Hokkoku Osho-Cup Shogi Tournament in Komatsu, Japan. The Matsue National College of Technology developed the computer program Tacos. Tacos played first and chose the static rook line in the opening. Professional Hashimoto followed the opening line while changing his bishop with the bishop of Tacos. Tacos had

606-554: A blunder of their own and potentially missing the key vulnerability of the first blunder. Played at the USSR Chess Championship in 1937, held in Tbilisi , this game featured a double blunder. Ragozin was planning to trade rooks with 40...Rc7 41.Rxc7 Bd6+ as this would transpose the game into a winning bishop versus knight endgame for Black. Therefore, Ragozin played 40...Rc7?? , not realizing that after 41.Rxc7,

707-469: A draw, Kramnik, playing Black, was generally considered in a comfortable position in Game 2, and he thought so himself apparently, as he refused a draw by avoiding a potential threefold repetition on 29...Qa7. Kramnik's troubles began when he decided to play for a win and pushed his a-pawn, 31...a4. Commentators, including American grandmaster Yasser Seirawan , voiced concerns about Kramnik's intentions and

808-431: A forked version of Winboard. Included engines are: Shokidoki, which can play the smaller variants with drops (i.e. Minishogi ); and HaChu, a large Shogi variant engine designed for playing Chu Shogi and has improved in strength over time. 将棋ぶらうざQ (Shogi Browser Q) is a free cross-platform (Java) GUI, that can run USI engines and compete on Floodgate. Since v3.7 both Japanese and English languages are available. BCMShogi

909-520: A gold can't be used for this purpose because that gold would come between the rook and the silver on rank 2 allowing Black to take the silver for free. Therefore, the suggested move is to use the rook to defend both 63 and 22. Black now drops a pawn to put the king in check. This move tries to force White's rook to capture the pawn at 52 with White's rook (Rx52), which will allow Black to successfully promote their bishop at 63 and attack White's rook (Bx63). Kitao considers this position uncertain compared to

1010-519: A good development with some advantages in the opening and middle game even until move 80. Many amateur players expected Tacos to win. However, professional Hashimoto defended and Tacos played strange moves. Tacos lost. On 14 October 2005, the Japan Shogi Association banned professional shogi players from competing against a computer. The Japan Shogi Association said the rule is to preserve the dignity of its professionals, and to make

1111-399: A key square. Instead, White blundered with 69.Kc3?? and after 69...Kc5 White resigned, as he loses his last pawn: 70.Kb3 Kd4 or 70.Kd3 Kb4 71.Ke3 Kc4 72.Kf3 Kd4 73.Kg3 Kxe4. Thus, the position after 69.Kc3?? Kc5 is reciprocal zugzwang: if Black were to move, it would be a draw, while if White were to move, Black wins. During the ninth game between Ian Nepomniachtchi and Magnus Carlsen in

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1212-487: A loss for the blunderer, but led to an embarrassing draw for the British GM Murray Chandler . In the diagram position, Chandler is completely winning. His opponent, Susan Polgar , played the wily trap 53...Ng8–h6 !? . Chandler realized that after 54.gxh6+ Kxh6 he will be left with the considerable material advantage of a rook pawn and bishop against a bare king . However, since the bishop

1313-411: A loss of material, checkmate, or anything similar. It is usually caused by some tactical oversight, whether due to time trouble , overconfidence, or carelessness. Although blunders are most common in beginner games, all human players make them, even at the world championship level. Creating opportunities for the opponent to blunder is an important skill in over-the-board chess. What qualifies as

1414-464: A network of 169 computers. The 4 engines voted on the best moves. Akara selects the move with the most votes. If there is a tie vote then Akara selects Gekisashi's move. Researchers at the University of Tokyo and the University of Electro-Communications developed Akara. Shimizu moved first and resigned in 86 moves after 6 hours and 3 minutes. Shimizu said she was trying to play her best as if she

1515-428: A pawn and giving Carlsen winning positions that he converted to win the match. Chess players and commentators widely believed that Nepomniachtchi's mental state was significantly impacted by the nearly 8-hour long game 6 , and that the blunder in game 11 might have been him giving up on the match to get it over with. Following a blunder, the opponent might not expect the move to be made and might overlook it, committing

1616-439: A pawn down, and to hold the draw, he either needs to preserve his last pawn, or (if Black decides to play Ke6 followed by f5) bring the king close enough to the e-file and stop the king from reaching any key squares. The correct move to draw is 69.Kd2!, when 69...Kc5 70.Kc3 keeps the opposition and prevents Black from penetrating, while 69...Ke6 70.Ke3 f5 71.exf5+ Kxf5 72.Kf3 prevents the king from advancing any further and reaching

1717-436: A rating equivalent to first or third dan. Bonanza was a little stronger than before due to program improvements and a faster computer. Watanabe prepared for a weaker Bonanza as Watanabe studied old Bonanza game records. Bonanza moved first and played Fourth File Rook Bear-in-the-hole as Watanabe expected. Watanabe thought some of Bonanza's moves were inferior. However, Watanabe deeply analyzed these moves thinking that maybe

1818-523: A robotic arm to move the pieces for the computer. Ōshō and Kiō champion Akira Watanabe wrote in his blog that "a human cannot think of some of Ponanza's moves such as 60.L*16 and 88.S*79. I am not sure they were the best moves or not right now, but I feel like I'm watching something incredible." Kisei , Ōi and Ōza champion Yoshiharu Habu told The Asahi Shimbun , "I felt the machines were extraordinarily strong when I saw their games this time." On Saturday 19 July 2014, Tatsuya Sugai once again got

1919-401: A second game. Tsutsukana was the same version that beat Funae on 6 April 2013. The computer was one Intel processor with 6 cores. Funae won. In 2013, the Japan Shogi Association announced that five professional shogi players would play five computers from 15 March to 12 April 2014. On 7 October 2013, the Japan Shogi Association picked the five players. The professional shogi players played

2020-411: A team of two amateurs. One amateur, Mr. Kosaku, was a Shoreikai three Dan player. The other amateur, Mr. Shinoda, was the 1999 Amateur Ryuo. The allotted time for the amateurs was main time 1 hour and then 3 minutes per move. The allotted time for the computer was main time 25 minutes and then 10 seconds per move. On 21 December 2011, computer program Bonkras crushed retired 68-year-old Kunio Yonenaga ,

2121-414: A user interface. USI was designed by Norwegian computer chess programmer Tord Romstad in 2007. Tord Romstad based USI on Universal Chess Interface (UCI). UCI was designed by computer chess programmer Stefan Meyer-Kahlen in 2000. Shogidokoro can automatically run a tournament between two programs. This helps programmers to write shogi programs faster because they can skip writing the user interface part. It

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2222-483: A way to go, but now we have to recognize that they've reached the point where they are getting to be a match for professionals." Watanabe further clarified his position on computers playing shogi in the Yomiuri Shimbun on 27 June 2008 when he said "I think I'll be able to defeat shogi software for the next 10 years". Another indication Bonanza was far below the level of professional Watanabe came 2 months after

2323-587: A win. Sometimes players, including strong grandmasters, resign in a won position instead of a lost position. Chess historian Tim Krabbé calls this kind of mistake "the ultimate blunder". In this 1902 game between Ignatz von Popiel and Georg Marco , the black bishop on d4 is pinned to the rook on d7, and there are no additional friendly pieces to come to its defense. Seeing no way to save his bishop, Black resigned, missing 36...Bg1!, threatening ...Qxh2# and leaving no way for White to save both his queen and rook while staving off checkmate. Tim Krabbé called this

2424-538: Is 15 minutes per player, sudden death. From 2011 to 2018, the Floodgate's number one program increased by 1184 points, an average of 169 points per year. The annual computer vs computer world shogi championship is organized by the Computer Shogi Association (CSA) of Japan. The computers play automated games through a server. Each program has 25 minutes to complete a game. The first championship

2525-611: Is about to fall. Fischer played the blunder 30...Nd6?? cutting the game short. After Najdorf played 31.Nxd6, Fischer resigned because he realized after Najdorf's response that 31...Qxd6 32.Nxb7 wins a piece because 32...Rxb7 33.Qc8+ is a fork that wins the rook on b7, so White wins at least a minor piece . Najdorf commented on Black's 29...Rb8: "There is no satisfactory defense. If 29...Ba8 then 30.Nb6 or 30.Qf5 would win. ... I had to win minor material (the pawn at f4) but this [30...Nd6 ? ] decides immediately. Fischer, demoralized because of his inferior position, did not notice

2626-487: Is also useful for testing changes to a program. Shogidokoro can be used to play shogi by adding a shogi engine to Shogidokoro. Some engines that will run under Shogidokoro are the following: The interface can also use tsumeshogi solver-only engines like SeoTsume (脊尾詰). The software's menus have both Japanese and English language options available. XBoard /WinBoard is another GUI that supports shogi and other chess variants including western chess and xiangqi. Shogi support

2727-687: Is an English language graphical user interface for the USI protocol and the WinBoard shogi protocol. It is no longer developed and currently is unavailable from the author's website. Floodgate is a computer shogi server for computers to compete and receive ratings. Programs running under Shogidokoro can connect to Floodgate. The GPS team created Floodgate. Floodgate started operating continuously in 2008. The most active players have played 4,000 games. From 2008 to 2010, 167 players played 28,000 games on Floodgate. Humans are welcome to play on Floodgate. The time limit

2828-505: Is from game 23 of the 1892 World Championship in Havana, Cuba . Chigorin , playing White, is a piece up ( Steinitz lost a knight for a pawn earlier in the game), but his bishop is forced to stay on d6 to protect both the rook on e7 and the pawn on h2. If he won, Chigorin would have tied the match and sent it to a tiebreaker game. After 31...Rcd2, he played 32.Bb4?? . Steinitz replied 32...Rxh2+ and Chigorin immediately resigned (in light of

2929-481: Is harder in shogi than in chess because of the larger number of possible moves. A program will stop searching when it reaches a stable position. The problem is many positions are unstable because of the drop move. Finally, the "endgame" starts when the king is attacked and ends when the game is won. In chess, there are fewer pieces which leads to perfect play by endgame databases; However, pieces can be dropped in shogi so there are no endgame databases. A tsumeshogi solver

3030-434: Is known as the 5-Move Bomb (五手爆弾 go-te bakudan ). If Black continues advancing their rook pawn for an attack at 23 instead of defending with a gold as recommended by joseki, after a pawn exchange on the second file involving the rook, White can start a counterattack by advancing their pawn on the eighth file. Once Black captures White's pawn at 86, rather than recapturing Black's pawn with their rook (as happens in

3131-469: Is one of the most traditional openings dating back to over 250 years ago. Originally, unlike the Yagura (Fortress) openings , in which piece positioning advances by blocking the bishop diagonals, all ways in which the piece positioning proceeds without closing the bishop diagonals received the name aigakari (lit. 'mutual attack'), which has been traditionally translated to English as Double Wing Attack. Later,

Double Wing Attack - Misplaced Pages Continue

3232-528: Is the first Denou-sen match. The game had 113 moves. Time allowed was 3 hours and then 1 minute per move. Bonkras moved first and used a ranging rook opening. Yonenaga made the same second move, K-6b, as in the previous game he lost. Bonkras ran on a Fujitsu Primergy BX400 with 6 blade servers to search 18,000,000 moves per second. Yonenaga used 2 hours 33 minutes. Bonkras used 1 hour 55 minutes. Bonkras evaluated its game with Yonenaga in January 2012. Denou-sen

3333-400: Is to advance the side or edge pawn allowing the bishop to escape, which leads to a different set of josekis. Another alternative is for Black to play a Floating Rook strategy and prevent White from making a pawn exchange, although Black's Rook becomes somewhat exposed. 4. P-24 Px24, 5. Rx24. Next, Black initiates a pawn attack on the second file leading to a pawn exchange involving

3434-416: Is unable to control the promotion square h8, Black will draw if she is able to get her king to control h8 due to the wrong rook pawn fortress . But Chandler calculates further, and realizes that it is he who will win control over the h8 square after 55.Kf6, and thereby win the game. Therefore, Chandler played 54.gxh6+?? , but instead of the expected 54...Kxh6, Polgar played 54...Kh8, leading to almost

3535-500: Is used to quickly find mating moves. In the 1980s, due to the immaturity of the technology in such fields as programming , CPUs and memory , computer shogi programs took a long time to think, and often made moves for which there was no apparent justification. These programs had the level of an amateur of kyu rank. In the first decade of the 21st century, computer shogi has taken large steps forward in software and hardware technology. In 2007, top shogi player Yoshiharu Habu estimated

3636-515: The Edo period (1603-1868) the common joseki for Double Wing Attack consisted of advancing the rook pawn after opening the bishop diagonals, and after exchanging pawns, retreating the rook without capturing the side pawn. At the beginning of the Heisei era (1989-2019), the main line became to advance the rook pawns without opening any of the bishop diagonals, and then to retreat the rook after exchanging

3737-760: The World Chess Championship 2014 in Sochi between Magnus Carlsen and Viswanathan Anand also featured a double blunder. Carlsen adopted the space-gaining Maróczy Bind setup against the Kan Variation of the Sicilian Defence , and accepted a set of isolated doubled pawns in return for active play. After an early queen exchange he soon developed a commanding position and appeared to have excellent winning chances. On his 26th move Carlsen played 26.Kd2?? , immediately realizing after making

3838-541: The World Chess Championship 2021 , the game was equal until Nepomniachtchi played 27.c5?? . This move handed the advantage to Carlsen, since after 27...c6, the White bishop on b7 is trapped and the knight on b3 cannot move to c5 to defend it. The game followed with 28.f3 Nh6 29.Re4 Ra7 30.Rb4 Rb8 31.a4 Raxb7, leaving Carlsen a bishop up. Nepomniachtchi resigned eight moves later. Nepomniachtchi had previously blundered in game 8 and would do so again in game 11, both times losing

3939-534: The blind swine mate 33.Kg1 Rdg2#), losing the match. This game between Ernst Gruenfeld and Alexander Alekhine is from Karlsbad tournament in 1923, round 2. In position on the diagram, White is to make his 30th move. Gruenfeld played 30.f3?? which immediately loses to 30...Rxd4 because 31.exd4 is impossible: after 31...Bxd4+ 32.Kf1 Nf4 33.Qxe4 Qc4+ 35.Ke1 Nxg2+ 36.Kd2 Be3+ and White will at least lose his queen. The game ended shortly afterwards: 31.fxe4 Nf4 32.exf4 Qc4 33.Qxc4 Rxd1+ 34.Qf1 Bd4+ and he resigned due to

4040-495: The grandmaster level. However, in 2005 the International Chess Federation ( FIDE ) banned it, instead requiring that the move be made before being written down. The US Chess Federation also implemented this rule , effective as of January 1, 2007 (a change to rule 15A), although it is not universally enforced. Strong players, even grandmasters, occasionally make critical blunders. This position

4141-413: The opening book , the search algorithm and the endgame . The "opening book" helps put the program in a good position and saves time. Shogi professionals, however, do not always follow an opening sequence as in chess, but make different moves to create good formation of pieces. The "search algorithm" looks ahead more deeply in a sequence of moves and allows the program to better evaluate a move. The search

Double Wing Attack - Misplaced Pages Continue

4242-501: The tokin with the rook, which is defended by a silver. (Hosking suggests a variant in which the silver captures the tokin. See below.) From here, Black may exchange rooks. But, White is in a better position. Kitao suggests that taking the tokin with White's silver after move 17 is an inferior move. The reason is because Black will drop their bishop to 45 threatening to promote at 63 and further attack White's camp. At this point, White needs to defend 63. However,

4343-469: The tokin with the silver, Black can now use their newly obtained bishop in the next move. Black can drop their bishop to 45 (or 36) attacking 63. Computer shogi Computer shogi is a field of artificial intelligence concerned with the creation of computer programs which can play shogi . The research and development of shogi software has been carried out mainly by freelance programmers, university research groups and private companies. By 2017,

4444-458: The "earliest, most famous, and clearest example" of resigning with a winning position. In this game played in Budapest in 1955 between György Négyesy and Károly Honfi , Black saw that White's c3-knight is stopping ...Rd1#. Therefore, Black played 19...Qxa2+??, deflecting the knight. White agreed and resigned. Both players overlooked that after 20.Nxa2 Rd1+, the deflected knight can still stop

4545-474: The 1993 Meijin. They played 85 moves in 1 hour, 3 minutes 39 seconds on Shogi Club 24. Each player started with 15 minute time limit and an additional 60 seconds are added to each player's time limit per move. Yonenaga was gote (white) and played 2. K-62. This move was to confuse the computer by playing a move not in Bonkras's joseki (opening book). On 14 January 2012, Bonkras again defeated Yonenaga. This match

4646-522: The 21st century. Thus, a presentday Double Wing opening typically arises when the rook pawns are traded off the board first and only after this are the bishop diagonals opened (if they are opened at all), which prevents the Side Pawn Capture opening possibility. Consequently, the open bishop diagonal variations of Double Wing (without captured side pawns) are not commonly played by professional players (although they are occasionally seen). During

4747-580: The CSA tournament with five wins out of seven games. Bonkras ran on a computer with three processors containing 16 cores and six gigabytes of memory. Bonanza won second place on a computer with 17 processors containing 132 cores and 300 gigabytes of memory. Shueso won third place. The 2010 CSA winner, Gekisashi, won fourth place. Ponanza won fifth place. GPS Shogi won sixth place on a computer with 263 processors containing 832 cores and 1486 gigabytes of memory. In 2012, GPS Shogi searched 280,000,000 moves per second and

4848-474: The Double Wing Attack to threaten each opponent's bishop and to exchange the rook pawns activating the rook. From the start of the game, the pawn at the head of each bishop (23 for White, 87 for Black) is undefended. By advancing each player's rook pawn (at 83 for White, at 27 for Black), each player aims for their opponent's bishop head. Then, the initial strategy involved is to provide the head of

4949-414: The advantage by a move like 36.Qc7. However, he overlooked that the queen was en prise , played 36.Ng5?? and resigned after 36...Nxd6. This game between Miguel Najdorf and Bobby Fischer from the 1966 Piatigorsky Cup is an example where a player in a bad position breaks under the pressure. According to Mednis , Fischer's decisive error came earlier in the game, and here the black pawn on f4

5050-492: The average search depth was 22.2 moves ahead. Hiroshi Yamashita, the author of YSS, maintains a list of all shogi programs that played in World Computer Shogi Championship by year and winning rank. Some commercial game software which play shogi are Habu Meijin no Omoshiro Shōgi for Super Famicom , Clubhouse Games for Nintendo DS and Shotest Shogi for Xbox . On 18 September 2005

5151-399: The bishop with adequate defense and/or give the bishop an escape route from the advancing pawn. 1. P-26 P-84, 2. P-25 P-85. Following the joseki, both sides advance their rook pawns to the middle rank 5. 3. G-78 G-32. Then, golds are moved to defend each bishop's head. Note that the head of the bishop should be defended. (See: § Protecting the bishops below.) An alternative option

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5252-404: The bishop would be pinned to the king, and would therefore be a full blunder of a rook. Ebralidze started to calculate, not wanting to be in a lost endgame. He, too, had not realized that after 41.Rxc7 the bishop would be pinned. After Ebralidze had thought for around 15 minutes, according to Adrian Mikhalchishin , "the crowd went literally crazy." Someone in the audience shouted "Archil, take

5353-512: The bishop's head with a gold rather than immediately pushing their rook pawns again. If either player ignores protecting the bishop after move 4 (a blunder ), their bishop may get trapped by a pawn drop according to the famous josekis explained below. (A similar issue occurs in a Bishop Exchange opening where if bishop's head is not protected by a gold, then a pawn drop can occur.) 2. P-25   P-85 4. Rx24   P-86 5.P-24. This sequence of moves (1.P-26 P-84 2.P-25 P-85 3.P-24)

5454-407: The board to the screen and back, hardly able to believe that he had input the correct move. Fritz was displaying mate in one, and when Mathias executed it on the board, Kramnik briefly grasped his forehead, took a seat to sign the score sheet and left for the press conference." During it, he stated that he had planned the supposedly winning move 34...Qe3 already when playing 29...Qa7, and had rechecked

5555-517: The chance to play against Shueso in what was billed as the "Shogi Denou-sen Revenge Match". Sugai had already been beaten by Shueso four months earlier in game one of Denou-sen 3, so this was seen as his chance to gain revenge for that loss. The game was sponsored by both the Japan Shogi Association and the telecommunications and media company Dwango and was held at the Tokyo Shogi Kaikan (the Japan Shogi Association's head office). Although

5656-412: The choices for Black's rook are to either retreat or attack White's bishop. (Ignoring the bishop attack may lead to losing the rook.) If Black's rook retreats to rank 8 (as shown in the diagram), then White can promote their bishop to a horse at 57. From here, Black can finally capture White's bishop. After move 17, White must remove the threat of Black's tokin on 22. Aono and Kitao recommend taking

5757-457: The computer saw something that Watanabe did not see. Watanabe commented after the game that he could have lost if Bonanza had played defensive moves before entering the endgame. But the computer choose to attack immediately instead of taking its time (and using its impressive endgame strategies) which cost it the match. Bonanza resigned after move 112. After Bonanza's loss Watanabe commented on computers in his blog, "I thought they still had quite

5858-554: The fastest ways to win were 54.h4 and 54.Bf5 according to the Shredder tablebase . This example, from a game played in Linares in 2002, is one of the very rare circumstances where a grandmaster makes the worst move possible, the only one allowing checkmate on the next move. In this queen endgame , White has some advantage after 69.fxg6+ fxg6 70.Kf4 due to Black's weak pawn on c6. Beliavsky played 69.Kf4?? , however, overlooking

5959-496: The forced checkmate after 40.gxf3 Rg6+ 41.Kh1 Nf2# or 40.Kh1 Nf2#. Karpov went on to win the match and later beat Korchnoi again in 1981 in the " Massacre in Merano ". In this position, Black offered a draw. White asked Black to make a move first. According to the rules of chess (see draw by agreement ), Black must make a move in response to this request, and the draw offer cannot be retracted. Black played 28...Qxb2+!, which wins on

6060-460: The game, Miura said that "he should not have prepared for the game the way he did. He should have prepared for the game with a genuine sense of urgency, if only he knew, the computer was so strong." Miura expressed disappointment and said he had yet to figure out where he went wrong. The evaluation of the game by GPS is on the GPS Shogi web site. On 31 December 2013, Funae and Tsutsukana played

6161-435: The game. Aronian had seen 27...R8xf4, but playing quickly to avoid time trouble, he thought that White could strike back with 28.gxf4 Nxf4 29.Ra8+ since both 29...Kf7 and 29...Kh7 lose to the knight fork 30.Ng5+. He had missed, however, that the retreat 29...Bf8! ends White's brief counterattack and leaves White defenseless against the mate threat. The game was eventually drawn by perpetual check on move 48. The sixth game of

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6262-407: The games live with commentary. Hiroyuki Miura said before his game he would play with "all his heart and soul". Miura decided to use trusted opening theory instead of an anti-computer strategy . The computer played book moves and they castled symmetrically to defend their kings. The computer attacked quickly and Miura counterattacked with a drop move. More than 8 hours later Miura resigned. After

6363-403: The left of the board (in the case of Black's R-26 variation), or Climbing Silver or Reclining Silver using the right silver, which require both players to manage a wide range of moves and imagination. There is a wide variety of strategies, from quick attacks in which both players make use of their pawns in hand, to slow games in which both players castle their kings. The initial aim of

6464-424: The line after each subsequent move. After an exchange of queens, Black would win easily with his distant pawn; after 35.Qxb4 Qe2 or 35.Ng6+ Kh7 36.Nf8+ Kg8 Black also wins eventually. Chess journalist Alexander Roshal attempted to explain the blunder by saying that the mating pattern of a queen on h7 protected by a knight on f8 is extremely rare and not contained in a grandmaster's automatic repertoire. This game

6565-450: The match at the May 2007 World Computer Shogi Championship. Bonanza lost to the 2007 World Computer Shogi Champion YSS. Then YSS lost to amateur Yukio Kato in a 15-minute game. The winners of CSA tournaments played exhibition games with strong players. These exhibition games started in 2003. In each succeeding year, the human competition was stronger to match the stronger programs. Yukio Kato

6666-549: The mate with 21.Nc1. Sanguineti won playing white in this Mar del Plata tournament game in 1956. Najdorf with black pieces has a substantial material advantage, but due to Black's poor king safety, White has a forced win. Correct is 58.Qg8+ winning the bishop (58...Bf7 blocks the king's escape square on the seventh rank, allowing 59.Qd8 which leaves two mate threats, 60. Qd7# and 60. Qd6# which cannot both be prevented (59...Rxd4 60. Qd6#, 59...Rxg4 Qd7#, )). Instead, White played 58.Kd8?? (threatening 59.Qe7#), thinking that it won on

6767-421: The most of computer shogi as a potential business opportunity. The ban prevents the rating of computers relative to professional players. From 2008 to 2012, the Japan Shogi Association (with Kunio Yonenaga as president) did not permit any games between a professional and a computer. Blunder (chess) In chess , a blunder is a critically bad mistake that severely worsens the player's position by allowing

6868-417: The move that 26...Nxe5! (with a discovered attack on the g4-rook) 27.Rxg8 Nxc4+ ( zwischenzug ) 28.Kd3 Nb2+ 29.Ke2 Rxg8 leads to Black picking up two extra pawns and gaining excellent winning chances. Anand, not expecting the blunder, replied with 26...a4?? in less than a minute. He, too, saw the missed tactic immediately after making his move. Carlsen made no further mistakes and converted his advantage into

6969-481: The newspaper Asahi Shimbun in 2012. He estimated the computer played at the 4 dan professional level. Watanabe also said the computer sometimes found moves for him. On 23 October 2005, at the 3rd International Shogi Forum, the Japan Shogi Association permitted Toshiyuki Moriuchi , 2005 Meijin , to play computer shogi program YSS. Toshiyuki Moriuchi won the game playing 30 seconds per move with

7070-519: The night and into the next day and finally finished almost 20 hours after it started when Sugai resigned after Shueso's 144 move. Shogidokoro (将棋所) is a Windows graphical user interface (GUI) that calls a program to play shogi and displays the moves on a board. Shogidokoro was created in 2007. Shogidokoro uses the Universal Shogi Interface (USI). The USI is an open communication protocol that shogi programs use to communicate with

7171-423: The opponent's forcing moves . In particular, checks , captures , and threats need to be considered at each move. Neglecting these possibilities leaves a player vulnerable to simple tactical errors. One technique formerly recommended to avoid blunders was to write down the planned move on the score sheet , then take one last look before making it. This practice was not uncommon even at

7272-549: The pawns. However, starting in the second half of the 2010s, it became more frequent to delay the rook pawns exchange, without doing so immediately. Traditionally, the two most common positions to which the rook retreated have been R-26 and R-28 (in Black's case), but in recent years, the R-25 variation of Double Attack has also appeared in official tournaments. From this point on, several variants are possible, such as Twisting Rook on

7373-476: The playing site was closed to the public, the game was streamed live via Niconico Live with commentary being provided by various shogi professionals and women's professionals. Shuesho's moves were made by Denso's robotic arm. The initial time control for each player was eight hours which was then followed by a 1-minute byoyomi. In addition, four 1-hour breaks were scheduled throughout the playing session to allow both sides time to eat and rest. The game lasted through

7474-417: The popular chess variants. The higher numbers for shogi mean it is harder to reach the highest levels of play. The number of legal positions and the number of possible games are two measures of shogi's game complexity . The complexity of Go can be found at Go and mathematics . More information on the complexity of Chess can be found at Shannon number . The primary components of a computer shogi program are

7575-452: The position in which the rook captures the tokin. If White uses a gold to capture the checking pawn (Gx52), then the rook's defense of the silver will be blocked allowing Black to capture the silver (Rx22). However, Hosking has a different suggestion which Kitao does not consider. In contrast to Aono and Kitao, Hosking recommends the silver taking the tokin along with the defense of this silver as shown below. If White captures

7676-429: The recommended joseki), White can instead drop a pawn at the bishop's head (P*87). Black's bishop is now trapped. Although Black can also attack White's bishop with a pawn drop, White now has the initiative and will capture Black's bishop first. After Black captures White's tokin at 88 with a silver, with a bishop in hand, White can fork Black's rook and king pawn by dropping their bishop to 35. At this point,

7777-545: The response 69...Qb8#. According to Johannessen , it took a few moments for both players to realize that it was checkmate, and Beliavsky was a good sport over this mishap. In November 2006, reigning world chess champion Vladimir Kramnik competed in the World Chess Challenge: Man vs. Machine , a six-game match against the chess computer Deep Fritz in Bonn , Germany. After the first game had ended in

7878-511: The rook!" Further shouts from the audience followed. Eventually, Ebralidze shouted back "I can see that, you patzers!". Ebralidze played 41.Rd5?? , missing the free rook entirely. The game continued 41...Bf6 42.Nb5 Rc2+ 43.Kg3 a6 44.Rd7+ Ke8 45.Rc7??. Ebralidze lost his rook to the bishop fork 45...Be5+, and resigned. The game between the world's two highest-rated players in the 2012 Grand Slam Master's final in São Paulo and Bilbao (this game

7979-403: The rook. 5. ...P*23. White responds by dropping a pawn to 23 to push Black's rook back. After move 10 of Double Wing Attack, the joseki branches off into different variants depending on which square the rook moves down to. (See § Further strategy branches below.) After advancing the rook pawns in the first four moves (1. P-26 P-84, 2. P-25 P-85), it is important for both players to protect

8080-464: The same king, bishop, and rook pawn versus bare king situation as Chandler had calculated that he would avoid, and the small difference that White has two rook pawns rather than one has no effect on the result. Black controls the h8 square and cannot be chased or squeezed away from it, and so White cannot promote his pawn. After 55.Bd5 Kh7 56.Kf7 Kh8 the players agreed to a draw . Chandler had numerous moves that would have maintained his winning position;

8181-410: The second type has bishop diagonals closed. The open bishop diagonal variations were most common historically being played from the 1700s and throughout the first part of the twentieth century. However, in modern shogi, the term Aigakari typically refers to the closed bishop diagonal variations. One reason is that the open bishop diagonal position shown in the adjacent diagram most often develops into

8282-590: The simple point." This position is from Game 17 of the 1978 World Championship between Viktor Korchnoi , the challenger, and the World Champion, Anatoly Karpov . Karpov, playing Black, is threatening a back-rank mate with 39...Rc1#. Korchnoi could have prevented this by moving his g-pawn (but not the h-pawn because 39.h3 or h4 leads to 39...Rc1+ 40.Kh2 Nf1+ 41.Kg1 Nfg3+ 42.Kh2 Rh1#), providing an escape square for his king. In serious time trouble, Korchnoi played 39.Ra1?? and resigned after 39...Nf3+ ! with

8383-407: The situation became more uncertain as the game went on with 32.Nxe6 Bxe3+ 33.Kh1 Bxc1 34.Nxf8, turning it into a likely draw. The game could have ended with 34...Kg8 35.Ng6 Bxb2 36.Qd5+ Kh7 37.Nf8+ Kh8 38.Ng6+. However, Kramnik's next move, 34...Qe3?? (a move awarded "???" originally by ChessBase on a story covering Kramnik's blunder, and even "??????" by Susan Polgar ), came as a big surprise and

8484-526: The spot (29.Kxb2 Rb3+ 30.Ka1 Ra8+ 31.Ba6 Rxa6#). White was so stunned he forgot he could still accept the draw offer, and resigned. This blunder was published in a one-off Not the British Chess Magazine organized by GM Murray Chandler in 1984, where it was voted the blunder of the year by a team of panelists. In this example, from a tournament in Biel in 1987, the game did not result in

8585-587: The spot. Miguel agreed, and resigned. Both players overlooked the defense 58...Rxg4, winning more material and allowing the black king to escape to f5. With the king on d8, White cannot play Qc8+, which would have won the rook. In the game between Victor Korchnoi against Geert Van der Stricht  [ nl ] , at the 2003 European Team Championship , Black seems helpless against White's kingside threats. Agreeing with this idea, Black resigned – presumably seeing 36...Nxe5! 37.Rxe6 Nxd3 (threatening 38...Nf4+ and 38...fxe6) 38.Rxh6+ gxh6 39.Qxh6#. He missed, however,

8686-526: The start of the game. Akara played with a ranging rook strategy and offered an exchange of bishops. Shimizu made a questionable move partway though the game, and Akara went on to win. Ryuo champion, Akira Watanabe, criticized Shimizu's game. On 19 November 2010, the Daily Yomiuri quoted Watanabe. Watanabe said, "Ms. Shimizu had plenty of chances to win". On 24 July 2011, there was a two-game amateur versus computer match. Two computer shogi programs beat

8787-628: The strategy of exchanging bishops first and then proceeding with the piece positioning began to be called Bishop exchange (Japanese: Japanese : 角換わり , romanized :  kakugawari ), while the strategy of capturing the pawn on 34 (i.e. the 'side pawn') after exchanging rooks once both bishop diagonals have been opened began to be called Side pawn capture ( Japanese : 横歩取り , romanized :  yokofudori ), openings that are now considered independent of aigakari . Double Wing openings have two general variations. The first one has both bishop diagonals open (that is, P-76 and P-34) while

8888-410: The strength of the 2006 world computer shogi champion Bonanza. He contributed to the newspaper Nihon Keizai Shimbun evening edition on 26 March 2007 about the match between Bonanza and then Ryūō Champion Akira Watanabe . Habu rated Bonanza's game at the level of 2 dan shogi apprentice ( shōreikai ). In particular, computers are most suited to brute-force calculation, and far outperform humans at

8989-415: The strongest programs were outperforming the strongest human players. Shogi has the distinctive feature of reusing captured pieces. Therefore, shogi has a higher branching factor than other chess variants. The computer has more positions to examine because each piece in hand can be dropped on many squares. This gives shogi the highest number of legal positions and the highest number of possible games of all

9090-408: The task of finding ways of checkmating from a given position, which involves many fewer possibilities. In games with time limits of 10 seconds from the first move, computers are becoming a tough challenge for even professional shogi players. The past steady progress of computer shogi is a guide for the future. In 1996 Habu predicted a computer would beat him in 2015. Akira Watanabe gave an interview to

9191-523: The unavoidable back-rank mate 35.Kh1 Rxf1#. This position arose in the 1956 Candidates Tournament in Amsterdam. Petrosian (White), enjoys a clear advantage with strong knights , active rooks and great mobility while Black's position is congested. Bronstein (Black) has for the last seven turns made aimless knight moves, Nc6–d4–c6–d4, while White had kept strengthening his position. Now he played Nd4–f5, threatening White's queen. White can preserve

9292-408: The winners of a preliminary computer tournament. The preliminary computer tournament was held 2–4 November 2013. Each player started with 5 hours at 10 am. After the 5 hours, the player must complete each move in 1 minute. There was a 1 hour lunch break at 12:00 and a half hour dinner break at 5 pm. Niconico is broadcasting the games live with commentary. Japanese auto parts maker Denso developed

9393-431: Was a shogi competition where humans faced off against machines. The second Denou-sen match was a five-game match sponsored by Niconico in which five professional shogi players played against five computers. The winners of the previous World Computer Shogi Championship played against professional shogi players. The primary time control was of 4 hours, and the secondary time control was 1 move in 60 seconds. Niconico broadcast

9494-598: Was added to WinBoard in 2007 by H.G. Muller. WinBoard uses its own protocol ( Chess Engine Communication Protocol ) to communicate with engines, but can connect to USI engines through the UCI2WB adapter. Engines that can natively support WinBoard protocol are Shokidoki, TJshogi, GNU Shogi and Bonanza. Unlike Shogidokoro, WinBoard is free/libre and open source, and also available for the X Window System as XBoard (for Linux and Mac systems). A number of Shogi variants, such as Chu Shogi and Dai Shogi , are playable against AI using

9595-508: Was described as possibly the "blunder of the century" and perhaps the "biggest blunder ever" by Susan Polgar, as Kramnik overlooked a mate in one. Deep Fritz immediately ended the game with 35.Qh7#. Seirawan later called Kramnik's move "a tragedy". From ChessBase : "Kramnik played the move 34...Qe3 calmly, stood up, picked up his cup and was about to leave the stage to go to his rest room. At least one audio commentator also noticed nothing, while Fritz operator Mathias Feist kept glancing from

9696-466: Was facing a human player. She played at the University of Tokyo on 11 October 2010. The allotted thinking time per player is 3 hours and 60 seconds byoyomi . 750 fans attended the event. This is the third time since 2005 that the Japan Shogi Association granted permission to a professional to play a computer, and the first victory against a female professional. Akara aggressively pursued Shimizu from

9797-496: Was in 1990 with six programs. In 2001, it grew to 55 programs. The championship is broadcast on the Internet. At the 19th annual CSA tournament, four programs (GPS Shogi, Otsuki Shogi, Monju and KCC Shogi) that had never won a CSA tournament defeated three of the previous year's strongest programs (Bonanza, Gekisashi and YSS). The top three winners of the 2010 CSA tournament are Gekisashi, Shueso and GPS Shogi. In 2011, Bonkras won

9898-528: Was played in May 2008 at the Baku Grand Prix from the FIDE Grand Prix 2008–2010 . In round 11, Étienne Bacrot played White against Ernesto Inarkiev . On move 23, he checked the black king with 23.Qe7+?? . Both players calmly wrote down the move. Bacrot then realized that his queen was under attack by the black knight and resigned. In this pawn ending (from a game in 2020), White is

9999-502: Was played in São Paulo) featured a double blunder. Carlsen , with White, played the tactical blunder 27.Bf4?? , and saw almost immediately that this loses to 27...R8xf4!, in effect winning a piece since taking the rook gives Black a forced mate: 28.gxf4 Nxf4 (threatening Qg2#) 29.Rg1 Qxh2+ 30.Kxh2 Rh3#. Carlsen waited for Aronian to make his move, and Aronian eventually played the otherwise solid 27...Bc3?? , allowing White back into

10100-401: Was played with 2 hours each and 1 minute byo-yomi per move after that. Those conditions favor Watanabe because longer time limits mean there are fewer mistakes from time pressure. Longer playing time also means human players can make long-term plans beyond the computer's calculating horizon . The 2 players were not at the same playing level. Watanabe was the 2006 Ryuo Champion and he gave Bonanza

10201-561: Was the Asahi Amateur Meijin champion. Toru Shimizugami was the Amateur Meijin champion. Eiki Ito, the creator of Bonkras, said in 2011, at present, top Shogi programs like Bonkras are currently at a level of lower- to middle-class professional players. The computer program Akara defeated the women's Osho champion Ichiyo Shimizu . Akara contained 4 computer engines: Gekisashi, GPS Shogi, Bonanza, and YSS. Akara ran on

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