Fat Fritz se impone a Stockfish (segunda parte)

por Elshan Moradiabadi
08/11/2019 – Ayer publicamos la primera parte del artículo sobre en la que anunciamos los resultados de los duelos oficiosos a 100 partidas entre Fat Fritz y las dos versiones de Stockfish, 8 y 10, respectivamente. Hoy vamos a retomar el tema y les mostraremos algunas partidas especialmente interesantes. El gran maestro ELSHAN MORADIABADI ha analizado las partidas para nosotros y explica los puntos fuertes de Fat Fritz. Por cierto... ¡La semana que viene (el 12 de noviembre) saldrá a la venta la nueva versión de nuestro programa de ajedrez, Fritz 17, que va a incluir el módulo Fat Fritz.

ChessBase 15 - Download ChessBase 15 - Download

¡Entrenarse como Carlsen, Caruana y compañeros! ¡Más rápido, más confortable y más eficiente! ¡Disfrute de las ventajas del flamante programa ChessBase 15!

Más...

La nueva generación de los duelos módulo vs. módulo

Los resultados de los duelos entre Fat Fritz y las dos versiones de Stockfish:

match results table

A continuación podrán ver las partidas comentadas por Elshan Moradiabadi.


Cuando la intuición humana entrena a la inteligencia artificial (2) 

Ya hemos hablado de las habilidades de Fat Fritz a la hora de jugar al ajedrez de manera dinámica. Ahora vamos a echar un vistazo a las ideas posicionales.  Fat Fritz se parece mucho a Leela por el simple hecho de que las redes artificiales neuronales se distinguen bastante en ese aspecto de los módulos tradicionales de ajedrez que funcionan a bruta fuerza. 

[Event "Rapid match 20m+10s"] [Site ""] [Date "2019.10.23"] [Round "5"] [White "Fat Fritz"] [Black "Stockfish 10 64 POPCNT"] [Result "1-0"] [ECO "A28"] [Annotator "Elshan"] [PlyCount "139"] [EventDate "2019.??.??"] [TimeControl "1200+10"] 1. c4 e5 2. Nc3 Nf6 3. Nf3 Nc6 4. e4 {0.17/13 25 The provided theory was already over a move ago, but FF amazes me by once again choosing the most fashionable line these days.} Bb4 {-0.30/33 62} 5. d3 {0.17/12 15} d6 {-0.20/ 30 18} 6. Be2 {0.16/12 35 This is also Magnus Carlsen's choice, though the general belief is that White should not let Black play a5.} a5 {-0.31/31 28 (0-0)} 7. O-O {0.15/12 56 (Le3)} O-O {-0.18/32 51} 8. h3 {0.13/12 11 (a3)} Bc5 {-0.44/32 53} 9. Be3 {0.11/14 40} Re8 {-0.39/29 19 (Sd4)} 10. Qd2 {0.13/11 31 (Sd5)} Bd7 {-0.43/31 13} 11. Bd1 {0.11/12 38 (Sd5)} h6 {-0.12/33 86} 12. Kh1 { 0.14/15 50 (Tc1)} Nh7 {-0.09/25 25 (Sd4)} 13. Nh2 {0.20/12 23} Rf8 {-0.11/30 64 } 14. Bg4 {0.21/13 41 (Tc1)} Nf6 {-0.15/28 14} 15. Bd1 {0.19/13 53 (Lxd7)} b6 { -0.15/33 151 (Lxe3)} 16. f4 {0.35/12 21 (Tc1)} Bxe3 {0.00/33 66} 17. Qxe3 { 0.33/14 16} Rb8 {0.00/34 34} 18. b3 {0.28/14 61 (fxe5)} Qe7 {-0.14/30 9} 19. f5 {0.27/13 7 (fxe5)} Nd4 {-0.37/30 15} 20. a4 {0.28/14 35 (Sd5)} c6 {-0.38/30 31 (Kh7)} 21. Nf3 {0.36/13 33} c5 {-0.27/32 17 (Sxf3)} 22. Ra2 {0.56/13 42 (Sh2)} Bc6 {0.00/39 56} 23. g4 {0.53/14 19} Nh7 {0.09/39 117} 24. Rh2 {0.50/13 26} Nxf3 {0.09/42 18 (g5)} 25. Bxf3 {0.60/16 52} Qh4 {0.09/44 14 (g5)} 26. Nd1 { 0.79/12 58 (Tg1)} Rbc8 {0.73/32 188 (Dg5)} 27. Be2 {0.94/11 29 (De2)} Rc7 { 0.97/32 60} 28. Rg1 {1.00/11 26 (Dg1)} g6 {0.88/28 11} 29. Qd2 {1.01/11 30} Kh8 {0.91/30 24 (Kg7)} 30. Ne3 {1.04/12 33} Qf6 {1.22/34 66 (Te8)} 31. h4 {1.13/16 32} g5 {1.12/39 43} 32. Nf1 {1.19/15 21} Qd8 {1.12/40 14 (gxh4)} 33. hxg5 { 1.25/14 39} Nxg5 {1.12/42 20 (hxg5)} 34. Rxh6+ {1.33/25 41} Kg7 {1.12/45 14 [#] This is a typical example of the advantage of AI (neural networks) over other brute force chess engines: intuition. I honestly don't know how they train themselves on it, but its resemblance to human intuition is astonishing. Here I had my computer run on this position and it only showed White's pseudo exchange-sac on depth 35. Needless to say, my engine couldn't detect the idea 3 or 4 moves in advance.} 35. Rxd6 $1 {1.41/28 22 Black is busted, the position is closed and white's extra space is the crucial factor here. It is the closest you can find human's intuition to AI.} Rh8+ {1.09/33 23} 36. Kg2 { 1.42/25 11} Qxd6 {1.75/34 22} 37. Qxg5+ {1.50/25 23} Kf8 {1.67/34 7} 38. f6 { 1.54/24 14} Ke8 {1.48/36 17} 39. Qg7 {1.55/22 0 (Th1)} Qf8 {1.72/36 12} 40. Qxf8+ {1.59/20 25 (Dg5)} Kxf8 {0.78/31 9} 41. Ne3 {1.60/21 0 (g5)} Rc8 { 2.21/41 73 (Ld7)} 42. g5 {1.58/17 88} Rg8 {2.23/36 39} 43. Kf3 {1.66/20 46 (Kf2)} Bd7 {2.24/31 7} 44. Nf5 {1.72/20 19} Rc6 {2.12/35 10} 45. Rg3 {1.79/20 42 (Kf2)} Bxf5 {2.12/33 4 (Th8)} 46. exf5 {2.46/18 62} Rd6 {2.87/37 13} 47. Ke4 {2.48/19 13} Rxf6 {2.96/39 15} 48. Kxe5 {2.50/17 17} Rc6 {2.92/40 7 (Th6)} 49. g6 {2.47/19 45} Ke7 {3.76/41 26 (Tc7)} 50. Bf3 {2.73/18 44} Rf6 {6.82/31 14} 51. Rh3 {2.74/19 10 (g7)} Rg7 {2.95/36 2} 52. gxf7 {2.76/17 17} Rgxf7 {2.97/40 6} 53. Rh5 {2.80/17 9} Rd6 {3.73/39 21 (Tf8)} 54. Bd5 {2.99/17 40} Rff6 { 4.21/32 11} 55. Rh7+ {3.02/16 12} Kd8 {4.58/32 10} 56. Rb7 {3.11/15 18 (d4)} Rh6 {2.83/36 3} 57. Be6 {3.12/15 13} Rxd3 {2.82/37 5} 58. Rxb6 {3.05/19 11} Kc7 {2.87/43 20} 59. Rb5 {2.90/17 30} Re3+ {3.07/41 9 (Kc6)} 60. Kd5 {3.38/12 40} Rexe6 {4.26/41 14 (Td3+)} 61. fxe6 {3.55/16 29} Rh5+ {5.37/40 10} 62. Ke4 { 3.42/16 0} Kd6 {5.86/39 10} 63. Rb6+ {3.68/14 16} Ke7 {6.35/35 11} 64. Ra6 { 3.71/13 9} Kf6 {6.37/36 10 (Tg5)} 65. Kd3 {3.97/12 20} Rg5 {7.38/32 10 (Ke7)} 66. Kc2 {3.91/11 35 (Kd2)} Rg2+ {5.28/26 3 (Th5)} 67. Kb1 {3.83/11 34} Rg5 { 8.77/35 17} 68. Kb2 {3.76/11 8 (Ka2)} Ke7 {9.39/32 10 (Tf5)} 69. Ka3 {3.83/11 11} Rh5 {10.49/35 10} 70. Rxa5 {3.43/11 10} 1-0

La siguiente partida concluyó en otro empate impresionante que recuerda un poco de los famosos duelos entre Kotov-Gligoric en Zúrich 1953. En esta partida, Fat Fritz no ofreció un solo sacrificio posicional, sino dos. Desde luego, esa partida demuestra que estamos hablando de un módulo muy "creativo", cuya "intuición" ha sido entrenada por los humanos al más alto nivel. 

Si uno hubiese dudado jamás en la precisión con la que suelen jugar los módulos de ajedrez, he aquí la prueba de que funcionan como un reloj de precisión. 

[Event "Rapid match 20m+10s"] [Site ""] [Date "2019.10.24"] [Round "12"] [White "Stockfish 10 64 POPCNT"] [Black "Fat Fritz"] [Result "1/2-1/2"] [ECO "A67"] [Annotator "Elshan"] [PlyCount "409"] [EventDate "2019.??.??"] [TimeControl "1200+10"] 1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 {Last book move.} 7. f4 {1.09/32 175} Bg7 {0.80/18 17} 8. Bb5+ {0.95/29 19} Nfd7 {0.81/20 18} 9. Bd3 {1.01/29 17 (a4)} Qh4+ {0.66/15 47 (0-0)} 10. g3 {0.98/29 17} Qd8 {0.66/18 13} 11. Nf3 {0.99/28 14} Na6 {0.66/17 60 (0-0)} 12. Nb5 {0.86/29 97 (0-0)} Nb6 {0.72/19 29} 13. f5 {0.80/29 15} O-O {0.83/21 69 (c4)} 14. O-O {1.00/28 13} c4 {0.84/20 0} 15. Bb1 {1.12/30 29 (Lc2)} Nd7 {0.24/17 40} 16. Kh1 {0.81/30 37 (Le3)} Qb6 {0.13/19 35} 17. a4 {0.98/30 24} Nac5 {0.11/19 17} 18. Bc2 {0.70/33 123 (Lf4)} a6 {0.06/20 42} 19. Nc3 {0.80/28 11} Qc7 {0.05/24 21 (Db4)} 20. g4 { 0.57/31 99 (Lf4)} Rb8 {-0.13/18 47} 21. a5 {0.12/31 72 [#] Unlike Leela, Fat Fritz has a sweet tooth for complexity, and while Leela deals with positional sacrifices as they happen (as a matter of necessity or not), Fat Fritz actively seeks complex lines, making it a great companion for those who take a liking to the games of Kasparov and Tal!} b6 {-0.16/20 28 weakening c6,} 22. Nd4 {0.43/25 17 (De1)} b5 {-0.26/22 54 Couldn't you do it earlier?!} 23. Nc6 { 0.69/27 16 [#]} b4 $3 {-0.25/31 31 The two exclamation points is for the aesthetic essence of the idea and not its soundness, though the idea is one of the three sound ones in this position.} 24. Nxb8 {0.00/35 79 (Sa4)} Qxb8 { -0.37/22 39} 25. Na4 {0.00/36 17} b3 {-0.38/23 20} 26. Bb1 {0.00/35 14} Nxa4 { -0.35/24 23} 27. Rxa4 {0.00/35 18} Qb5 {-0.35/26 0} 28. Ra3 {0.00/37 19 (Ta1)} Be5 {-0.47/17 63 White's attack and position is completely blocked.} 29. Qe2 { 0.15/28 23} Nc5 $5 {-0.47/18 0 Direct and aggressive.} 30. Bh6 {0.00/32 92 (Tf2)} Bd7 $5 {-0.29/32 86 [#] The second exchange sacrifice! I heard Fat Fritz had gone through all of the games on Mega Database, I am sure it took a close look at Kotov-Gligoric Zurich 1953.} 31. Bxf8 {0.00/36 15 (Tc1)} Kxf8 { -0.31/27 63} 32. Rc1 {0.00/39 17} Qb7 {-0.26/32 25} 33. Rxc4 $1 {0.00/40 22 Stockfish realizes the dire situation and gives back material for activity.} Bb5 {-0.23/31 18} 34. Bd3 {0.00/42 17} Bxc4 {-0.23/27 0} 35. Bxc4 {0.00/43 39} Qb4 {-0.23/26 0} 36. Ra1 {0.00/45 14} g5 $1 {-0.23/25 44 JIT: Just-in-time!} 37. Kg2 {0.00/36 41 (h4)} h6 {-0.46/22 120 [#] (Sa4) The position is dynamically balanced and the two giant engines concede to this fact after a hard-fought battle.} 38. h3 {0.00/38 52 (Tf1)} Kg8 {-0.90/19 61 (Ke7)} 39. Rf1 {0.00/37 16 (f6)} Bxb2 {-0.84/21 37 (Dxa5)} 40. Rb1 {0.00/40 13} Be5 {-0.81/19 23 (Ld4)} 41. Bxb3 {0.00/45 17} Qxa5 {-0.78/19 27 (Dc3)} 42. Qe3 {0.00/43 12} Qa3 {-0.76/21 108} 43. Qf3 {0.00/45 13} Qb4 {-0.77/17 0} 44. Bc2 {0.00/41 22} Qc4 {-0.76/23 10 (Dd2+)} 45. Rb8+ {0.00/45 15 (Lb3)} Kg7 {-0.89/17 45} 46. Bb1 {0.00/45 12} Nd7 {-0.85/18 62 (Kf6)} 47. Rb7 {0.00/42 16} Qc8 {-0.85/16 0 (Sc5) } 48. Rb3 {0.00/40 12} a5 {-0.84/17 21 (Sc5)} 49. Qe3 {0.00/41 14 (Dd1)} Nc5 { -0.90/16 73 (Kf6)} 50. Rb5 {0.00/39 15} Qa6 {-0.82/20 30} 51. Qe2 {0.00/44 12 (Txc5)} a4 {-0.77/15 26} 52. Qc4 {0.00/45 18} Qa7 {-0.75/21 7} 53. Ba2 { 0.00/41 11 (Db4)} Nd7 {-1.27/12 22} 54. Qd3 {0.00/42 29} Nf6 {-1.26/13 22} 55. Rb4 {0.00/45 11} Nd7 {-1.24/13 8} 56. Bc4 {0.00/42 12 (Tb5)} a3 {-1.38/13 23} 57. Ba2 {0.00/46 13} Qa5 {-1.35/13 31 (Dc5)} 58. Qb5 {0.00/45 15} Qa7 {-1.34/ 13 3 (Dc7)} 59. Qd3 {0.00/45 13 (De2)} Bb2 {-1.33/12 26 (Dc5)} 60. Qd2 { 0.00/41 11} Qa6 {-1.29/13 29} 61. Bb1 {0.00/40 11 (Lc4)} Be5 {-1.29/10 9 (Sc5)} 62. Qc2 {0.00/42 12 (La2)} Qa7 {-1.41/12 11} 63. Ba2 {0.00/46 25 (Db3)} Qa5 { -1.34/12 22 (De3)} 64. Qd2 {0.00/44 8 (Dc4)} Ba1 {-1.30/10 12 (Sc5)} 65. Rb2 { 0.00/42 12} Qc5 {-1.24/12 13 (Da6)} 66. Rb3 {0.00/42 13 (Tc2)} Be5 {-1.12/13 14 (Lb2)} 67. Bb1 {0.00/41 21} Bb2 {-0.81/17 10 (Sf6)} 68. h4 {0.00/40 15 (Tb7) } Bf6 {-0.99/19 6 (Kf6)} 69. hxg5 {0.00/42 12} hxg5 {-0.91/21 6} 70. Rb7 { 0.00/40 12 (De3)} Ne5 {-1.06/15 13} 71. Rb3 {0.00/43 11} Nd7 {-0.99/21 5 (Sxg4) } 72. Ba2 {0.00/46 17 (De3)} Ne5 {-1.11/14 13 (Dc4)} 73. Qc3 {0.00/37 8} Nc4 { -1.05/15 6} 74. Qd3 {0.00/38 10} Be5 {-0.74/18 31 (Lb2)} 75. Bb1 {0.00/41 10} Bf6 {-0.65/21 1} 76. Ba2 {0.00/41 11} Bd4 {-0.57/19 11 (Se5)} 77. Bb1 {0.00/42 10} Ne5 {-0.54/22 8 (Lf6)} 78. Qd2 {0.00/42 9} Kf6 {-0.53/21 5} 79. Qb4 { 0.00/44 11} Qxb4 {-0.52/20 4} 80. Rxb4 {0.00/47 15} Bc5 {-0.52/17 7} 81. Rb8 { 0.00/46 12 (Ta4)} Nxg4 {-0.57/12 16} 82. Re8 {0.00/44 10} Ne5 {-0.53/12 22} 83. Ba2 {0.00/47 21 (Kg3)} Nd7 {-0.52/11 19 (Le3)} 84. Kg3 {0.00/47 23} Ne5 { -0.49/11 10} 85. Bb1 {0.00/44 24 (Ta8)} Bb4 {-0.49/10 10 (Sc4)} 86. Ba2 { 0.00/42 6 (Ta8)} Be1+ {-0.51/10 7} 87. Kg2 {0.00/48 8} Bd2 {-0.50/11 14 (Lb4)} 88. Rd8 {0.00/48 8 (Ta8)} Bb4 {-0.50/11 5} 89. Ra8 {0.00/49 11 (Tb8)} Nd3 { -0.47/10 15 (Lc5)} 90. Bb1 {0.00/45 15 (Kg3)} Ne5 {-0.47/11 10} 91. Ba2 { 0.00/48 9 (Kg3)} Bc5 {-0.45/10 8} 92. Kg3 {0.00/48 53} Kg7 {-0.42/10 10 (Lb4)} 93. Bb3 {0.00/47 5 (Lb1)} Kh6 {-0.42/10 12 (Kf6)} 94. Bd1 {0.00/44 7 (Tg8)} Kh7 {-0.45/9 9 (Sd7)} 95. Bh5 {0.00/46 7 (Lc2)} Kg7 {-0.42/11 9} 96. Be2 {0.00/50 10} Kh7 {-0.39/11 11 (Sd7)} 97. Kh3 {0.00/50 9 (Ld1)} Kh6 {-0.41/10 8 (Kg7)} 98. Kg3 {0.00/51 8} Kg7 {-0.38/11 11} 99. Ra6 {0.00/52 12 (Lb5)} Kf6 {-0.41/10 12} 100. Kh3 {0.00/48 11 (Ta4)} Ke7 {-0.43/11 9} 101. Kg2 {0.00/52 9 (Lb5)} Bb4 {-0.47/11 12 (Kf6)} 102. Ra8 {0.00/50 18 (Lb5)} Bc5 {-0.42/12 10 (Kf6)} 103. Kg3 {0.00/49 7} Bb4 {-0.33/13 9 (Kf6)} 104. Bh5 {0.00/42 8 (Ta4)} Nd7 {-0.41/ 12 10 (Kf6)} 105. Ra4 {0.00/45 10} Bc5 {-0.38/14 3} 106. Be2 {0.00/54 28} Nb6 { -0.35/13 9 (Se5)} 107. Ra6 {0.00/51 6} Nd7 {-0.33/13 6} 108. Kg4 {0.00/51 11 (Ta4)} f6 {-0.39/14 11 (Kf6)} 109. Bb5 {0.31/48 7} Ne5+ {-0.34/15 6} 110. Kg3 { 0.31/52 7 (Kh5)} Kd8 {-0.40/11 11} 111. Bf1 {0.31/50 8 (Ta4)} Kc7 {-0.37/11 24} 112. Be2 {0.31/51 7 (Ta4)} Kb7 {-0.37/10 10 (Kd8)} 113. Kh2 {0.31/43 7 (Ta4)} Kc8 {-0.42/10 9 (Kc7)} 114. Kg3 {0.30/53 47} Kc7 {-0.37/9 11 (Kd8)} 115. Bf1 { 0.30/50 10 (Ta4)} Nd7 {-0.36/10 10 (Kd7)} 116. Bc4 {0.29/46 6 (Lb5)} Kb7 { -0.37/10 10 (Se5)} 117. Bb5 {0.29/51 8} Ne5 {-0.37/10 4} 118. Bf1 {0.28/48 16 (Le2)} Kb8 {-0.36/10 16 (Kc7)} 119. Ra5 {0.21/51 6 (Lb5)} Kc8 {-0.37/9 9 (Kb7)} 120. Be2 {0.20/53 6 (Ta4)} Nd7 {-0.37/9 11 (Kc7)} 121. Bb5 {0.20/48 13 (Ta4)} Ne5 {-0.34/10 4} 122. Bf1 {0.20/54 8 (Le2)} Nd7 {-0.38/9 16 (Kc7)} 123. Ra8+ { 0.11/45 9 (Lb5)} Kc7 {-0.37/11 8 (Kb7)} 124. Bb5 {0.01/49 24 (Ta4)} Ne5 { -0.36/11 5} 125. Bf1 {0.01/53 7 (Le2)} Kb6 {-0.31/10 16 (Lb4)} 126. Ra6+ { 0.00/52 9 (Ta4)} Kb7 {-0.29/10 7 (Kc7)} 127. Be2 {0.00/46 31 (Ta4)} Kc8 { -0.30/10 13 (Kc7)} 128. Bd1 {0.00/50 5 (Ta4)} Nd7 {-0.37/11 12 (Kc7)} 129. Bb3 {0.00/50 11 (Le2)} Ne5 {-0.41/10 10 (Kb7)} 130. Ra8+ {0.00/43 5 (Ld1)} Kc7 { -0.39/13 5} 131. Ba2 {0.00/47 9 (Tf8)} Nd7 {-0.36/10 9 (Sd3)} 132. Rh8 { 0.00/41 10 (Te8)} Be3 {-0.33/10 16 (Ld4)} 133. Kf3 {0.00/43 6 (Ta8)} Bc1 { -0.40/10 7} 134. Ra8 {0.00/44 7 (Th7)} Nc5 {-0.45/12 7 (Kb7)} 135. Bc4 { 0.00/42 13} Kb7 {-0.44/14 6 (Lb2)} 136. Ra5 {0.00/42 5} Nd7 {-0.43/13 5} 137. Rb5+ {0.00/41 10} Ka7 {-0.42/12 16 (Kc7)} 138. Ke2 {0.00/42 6 (Ta5+)} Ne5 { -0.48/12 14 (Lb2)} 139. Ba2 {0.00/44 7} Bb2 {-0.43/13 12 (Sd7)} 140. Kd2 { 0.00/42 8 (Ke3)} Nd7 {-0.52/11 9} 141. Ke3 {0.00/44 8 (Ke2)} Bc3 {-0.50/11 13 (Lc1+)} 142. Rb3 {0.00/45 6 (Lb1)} Bb2 {-0.61/12 5} 143. Rb5 {0.00/50 12 (Tb4)} Ne5 {-0.39/11 15 (Lc1+)} 144. Rb4 {0.00/44 7 (Ke2)} Nf7 {-0.36/11 11 (Sd7)} 145. Bc4 {0.00/42 14 (Tb5)} Ka8 {-0.30/12 10 (Se5)} 146. Kd3 {0.00/43 13 (Le2)} Ne5+ {-0.16/14 9} 147. Kc2 {0.00/46 8} g4 {-0.11/15 6} 148. Kb1 {0.00/44 20 (Lf1)} g3 {-0.23/18 7} 149. Bf1 {0.00/46 8} Nf3 {-0.15/20 5} 150. Bh3 {0.00/43 14} Ka7 {-0.10/21 11} 151. Ka2 {0.00/46 6} Ng1 {-0.07/21 20} 152. Bf1 {0.00/45 13} Nf3 {-0.08/22 0} 153. Bh3 {0.00/46 15} Ne1 {-0.05/19 6 (Sg1)} 154. Rb3 { 0.80/35 5} Be5 {-0.03/21 3 (g2)} 155. Rxa3+ {0.84/36 6} Kb6 {0.03/20 7} 156. Re3 {0.84/43 7} Nc2 {0.06/19 5} 157. Rb3+ {0.83/45 13} Kc5 {0.08/18 6} 158. Kb1 {0.83/49 9} Nd4 {0.09/17 6} 159. Rc3+ {0.82/48 12 (Td3)} Kb4 {0.06/14 24} 160. Rd3 {0.82/49 6} Kc4 {0.10/14 13 (Sb5)} 161. Re3 {1.09/46 5} Nb5 {0.16/15 29 (Kc5)} 162. Kc2 {1.07/45 7} Nd4+ {0.15/13 0} 163. Kd1 {1.00/50 9} Kb5 {0.16/13 15 (Lf4)} 164. Ra3 {1.00/45 6 (Lf1+)} Kb4 {0.19/12 9} 165. Ra2 {1.00/47 7 (Ta8) } Kc3 {0.16/10 15} 166. Bf1 {1.00/51 8} Nb3 {0.19/11 6} 167. Ra8 {1.00/52 12 (Ta3)} Nc5 {0.17/10 11 (Kd4)} 168. Bg2 {1.00/49 7 (Ke2)} Nb3 {0.15/10 9} 169. Bf1 {1.00/55 8 (Ta3)} Nc5 {0.16/10 11 (Kd4)} 170. Bg2 {1.00/52 8 (Ke2)} Nb3 { 0.13/9 9} 171. Ra4 {1.00/54 7 (Ta3)} Kd3 {0.14/10 16} 172. Ke1 {1.00/52 12 (Ta3)} Nd4 {0.05/10 7 (Lc3+)} 173. Ra3+ {1.00/45 7} Kc2 {0.07/11 8} 174. Bf1 { 1.00/50 7} Bf4 {0.14/11 11 (Sb3)} 175. Ra2+ {1.00/47 9} Kc3 {0.18/11 13 (Kc1)} 176. Kd1 {1.00/47 8 (Ta8)} Be5 {0.16/10 8} 177. Ra4 {1.00/55 9 (Ta8)} Nb3 { 0.15/10 12} 178. Rc4+ {1.00/56 12} Kb2 {0.19/10 0} 179. Rc2+ {1.00/60 21 (Tc8)} Ka3 {0.22/10 13} 180. Rc6 {1.00/50 15 (Tc8)} Nc5 {0.16/9 16 (Kb2)} 181. Kc2 { 1.27/43 4 (Tb6)} Kb4 {0.19/10 15 (Sxe4)} 182. Rc8 {1.58/43 6} Ka5 {0.20/9 10} 183. Bg2 {1.58/46 8 (Tb8)} Kb4 {0.17/8 10} 184. Bf1 {1.58/44 7 (Kd2)} Ka5 { 0.18/9 10} 185. Ra8+ {1.29/45 58 (Tb8)} Kb6 {0.18/9 10} 186. Bd3 {1.14/45 13 (Tb8+)} Kb7 {0.12/9 8} 187. Rg8 {1.14/45 8} Kb6 {0.15/9 9 (Kc7)} 188. Rg7 { 1.14/41 5 (Lf1)} Ka5 {0.12/9 10 (Lf4)} 189. Rc7 {1.14/45 6 (Lf1)} Kb6 {0.10/9 9 } 190. Rg7 {1.14/46 6} Ka5 {0.11/9 11} 191. Rg4 {1.14/46 8 (Lf1)} Kb4 {0.09/9 13 (Kb6)} 192. Rg8 {1.14/44 10 (Lf1)} Ka4 {0.11/9 10 (Sd7)} 193. Rc8 {1.13/47 36 (Lf1)} Kb4 {0.11/9 10} 194. Rf8 {1.05/49 13 (Ta8)} Ka5 {0.11/9 11 (Ka3)} 195. Rb8 {1.05/42 4} Nd7 {0.11/10 8 (Lf4)} 196. Rb1 {1.05/40 5} Nc5 {0.12/10 5 (Lf4)} 197. Kd2 {1.05/43 9} Ka4 {0.12/10 9 (Lf4+)} 198. Bb5+ {1.04/45 11 (Ke3)} Ka3 {0.11/10 14 (Ka5)} 199. Kc2 {1.04/48 4} Ka2 {0.10/11 6 (Ld4)} 200. Be2 { 1.04/49 7 (Lf1)} Ka3 {0.08/9 8} 201. Rb8 {1.00/48 14} Ka4 {0.05/9 9 (Sxe4)} 202. Bf1 {1.00/45 4} Ka5 {0.04/7 19 (Lf4)} 203. Bc4 {0.00/58 29 (Tb1)} Nd7 { 0.00/5 11} 204. Ra8+ {0.00/78 7 (Tb1)} Kb4 {0.00/2 12} 205. Bf1 {0.00/127 0 Draw agreed.} 1/2-1/2

La mayoría de los módulos de ajedrez suelen obtener resultados más o menos idénticos cuando la partida llega a la fase final, porque todos trabajan con los tablebases de finales. 

Sin embargo, hasta en aquellos casos, Fat Fritz procura ver todavía más y se esfuerza para resolver los finales de la mejor manera posible, incluso si son muy complicados. Siempre  procura encontrar ideas activas y aspira dominar la situación. Su preferencia por el juego profiláctico es una cosa que me gusta especialmente.

Echemos un vistazo a la siguiente partida. Fat Fritz está procurando salvar una posición desfavorable para él y lo hace de una manera muy poco convencional, siguiendo a paso firme sus propios principios. 

[Event "Rapid match 20m+10s"] [Site ""] [Date "2019.10.24"] [Round "13"] [White "Fat Fritz"] [Black "Stockfish 10 64 POPCNT"] [Result "1/2-1/2"] [ECO "A87"] [Annotator "Elshan"] [PlyCount "145"] [EventDate "2019.??.??"] [TimeControl "1200+10"] 1. d4 f5 2. g3 Nf6 3. Bg2 g6 4. Nf3 Bg7 5. O-O O-O 6. c4 d6 7. Nc3 Qe8 8. d5 { Last book move.} Na6 {0.25/31 95} 9. Be3 {0.69/13 31} Bd7 {0.17/31 51} 10. Rb1 {0.73/13 20 (Tc1)} c5 {0.37/30 47 (c6)} 11. Qd2 {0.75/18 26} Nc7 {0.44/31 19} 12. b4 {0.72/18 34} cxb4 {0.32/32 17} 13. Rxb4 {0.73/19 13} b6 {0.59/36 107} 14. h3 {0.72/18 58 (Tb3)} Na6 {0.27/31 20 (Dc8)} 15. Rb3 {0.71/19 30} Qc8 { 0.44/32 22} 16. Nd4 {0.67/22 87} Nc5 {0.22/32 45 (Dxc4)} 17. Ra3 {0.86/18 22} Nfe4 {0.30/36 57 (Sce4)} 18. Nxe4 {0.90/17 32} Nxe4 {0.40/35 16} 19. Qd3 { 0.87/20 58 (Dc2)} Nc5 {0.33/36 20} 20. Qd1 {0.94/13 38 (Dd2)} Ne4 {0.33/36 26 (Lf6)} 21. Qd3 {0.89/18 35 (Dc2)} Nc5 {0.35/37 19} 22. Qd2 {0.88/23 24} Ne4 { 0.46/36 34} 23. Qc2 {0.83/24 15} b5 {0.43/36 22} 24. Bxe4 {0.81/24 23} Bxd4 { 0.42/35 17} 25. Bxd4 {0.81/24 20} fxe4 {0.48/37 65} 26. g4 {0.78/27 69 (Te3)} Qxc4 {0.14/33 20} 27. Qxe4 {0.77/31 0} b4 {0.48/35 45} 28. Rd3 {0.76/29 18} Rae8 {0.25/33 14} 29. Rd2 {0.75/27 23} e5 {0.26/38 98} 30. dxe6 {0.73/26 22} Rxe6 {0.26/36 13} 31. Qb7 {0.73/26 30} Rf7 {0.62/37 115 (Te7)} 32. Qb8+ { 1.07/19 92} Bc8 {0.33/34 13 (Te8)} 33. Bxa7 {0.67/21 125 (Le3)} Rb7 {0.00/38 13 (h5)} 34. Qa8 {0.24/19 32} d5 {0.00/43 19} 35. Rdd1 {0.15/21 27} Ra6 { 0.00/43 33} 36. Rc1 {0.14/20 16} Rbxa7 {0.00/41 28} 37. Qxc8+ {0.13/18 15} Qxc8 {0.00/45 28} 38. Rxc8+ {0.14/17 15} Kg7 {0.00/45 22} 39. Rb8 {0.13/16 141 (Tb1) } Rxa2 {0.00/42 16} 40. e3 {0.13/14 0} Rb2 {0.00/43 43 (d4)} 41. Kg2 {0.18/11 54 (Tb5)} Kf6 {0.00/40 24 (Td7)} 42. Kg3 {0.17/13 69} Rf7 {0.00/41 18} 43. Rd1 {0.17/14 8 (Tb6+)} Kg7 {0.00/41 15} 44. Rf1 {0.16/13 18} Rb3 {0.00/42 35} ( 44... Rd7 45. Rb5 d4 46. exd4 Rxd4 47. Rb7+ Kf6) 45. Kg2 {0.16/13 38 [#] Here is another difference between FF to any other engine or human way of thinking: It has a great interest in fortresses. Like the previous game, it creates a situation making it impossible for White to improve. By contrast, GMs would try to activate the king and trade the d-pawn for the e-pawn and hold a 2-3 endgame.} h5 {0.00/43 29} (45... Rd7 46. Rb5 d4 47. exd4 Rxd4) 46. Rb5 { 0.16/13 42 (Td1)} h4 $1 {0.00/40 23 (d4)} 47. Rxd5 {0.25/12 26} Rb2 {0.00/43 20 Now white is tied down.} 48. Rb5 {0.23/12 36 (Td4)} Kh6 {0.00/39 14 (b3)} 49. Rb8 {0.23/11 52 (Tb6)} Re7 {0.00/46 39 (b3)} 50. Re1 {0.26/11 24 (Kf3)} Rf7 {0.00/45 17} 51. Rf1 {0.19/13 9} b3 {0.00/46 10 (Te7)} 52. Rb5 {0.23/11 37} Kg7 {0.00/46 11} 53. Rb6 {0.22/11 22 (g5)} Kf8 {0.00/42 11 (Kh6)} 54. e4 {0.24/11 19 (g5)} Rf4 {0.00/37 12 (Kg7)} 55. e5 {0.19/12 18 (Kg1)} Ke7 {0.00/39 13 (g5)} 56. Kg1 {0.24/13 14} Kd7 {0.00/41 17 (Te4)} 57. e6+ {0.20/15 19 (Td1+)} Kc7 { 0.00/43 15} 58. Rb5 {0.14/16 19} Kd6 {0.00/41 16} 59. Rb6+ {0.12/15 13} Kc7 { 0.00/44 20} 60. Re1 {0.10/14 27 (e7)} Rfxf2 {0.00/46 9} 61. e7 {0.08/12 16} Rg2+ {0.00/45 24} 62. Kh1 {0.07/9 0} Rh2+ {0.00/46 19} 63. Kg1 {0.05/7 0} Rbg2+ {0.00/50 70 (Thg2+)} 64. Kf1 {0.12/13 0} Rf2+ {0.00/53 19 (Tb2)} 65. Kg1 { 0.13/10 0} Rfg2+ {0.00/47 17} 66. Kf1 {0.08/7 0} Rf2+ {0.00/50 20 (Td2)} 67. Kg1 {0.13/6 0} Rhg2+ {0.00/49 59} 68. Kh1 {0.08/6 0} Kxb6 {0.00/57 48 (Th2+)} 69. e8=Q {0.03/9 85} Rh2+ {0.00/58 5} 70. Kg1 {0.02/7 0} Rhg2+ {0.00/66 11} 71. Kh1 {0.01/5 0} Rh2+ {0.00/64 29} 72. Kg1 {0.00/3 0} Rhg2+ {0.00/67 8} 73. Kh1 { 0.00/2 0 Remis angenommen} 1/2-1/2

¡Que rápido aprende!

La siguiente partida es otro ejemplo más de lo bien que Fat Fritz "comprende" las estructuras de peones. En esta variante de la Alekhine, Fat Fritz se le impone a Stockfish 10 con gran estilo. 

[Event "Rapid match 20m+10s"] [Site ""] [Date "2019.10.24"] [Round "19"] [White "Fat Fritz"] [Black "Stockfish 10 64 POPCNT"] [Result "1-0"] [ECO "B04"] [Annotator "Elshan"] [PlyCount "145"] [EventDate "2019.??.??"] [TimeControl "1200+10"] 1. e4 Nf6 2. e5 Nd5 3. d4 d6 4. Nf3 {Last book move.} g6 {0.31/33 114} 5. Bc4 { 0.77/17 23} Nb6 {0.26/28 9} 6. Bb3 {0.77/17 13} Bg7 {0.23/30 20 (a5)} 7. Ng5 { 0.77/24 26 (De2)} e6 {0.10/29 20} 8. Qf3 {0.75/24 19} O-O {0.45/34 87 (De7)} 9. Qh3 {0.61/20 43} h6 {0.24/30 8} 10. Ne4 {0.55/20 77 (Sf3)} d5 {0.24/31 19} 11. Nc5 {0.55/17 0} Kh7 {0.24/32 24} 12. Be3 {0.58/17 40 (c3)} N8d7 {0.23/32 75} 13. Nxd7 {0.59/18 15} Bxd7 {0.20/31 11} 14. Nd2 {0.61/16 19} Na4 {0.22/35 42 (f5)} (14... c5) 15. O-O-O {0.70/17 53 (Tb1)} b6 {0.19/29 58 (b5)} (15... c5 16. Bxa4 Bxa4 17. dxc5 Qa5 18. Kb1 b6) 16. g4 {1.11/16 49 (Kb1)} c5 {0.15/27 11 } 17. Rhg1 {1.13/19 20 (c3)} Rh8 {0.50/32 69} 18. f4 {1.15/18 21} Qc7 {0.49/29 14 (Tc8)} 19. c3 {1.10/22 47} b5 {0.16/30 20} 20. Kb1 {1.11/21 23 (dxc5)} c4 { -0.09/28 11 (Tab8)} 21. Bxa4 {1.17/17 51} bxa4 {0.21/31 41} 22. a3 {1.19/15 19} Rab8 {0.58/33 133 (Thb8)} 23. Ka1 {1.37/12 51} Rb7 {0.59/35 12 (Tb6)} 24. Nb1 { 1.50/11 48 (Tb1)} Kg8 {1.07/32 87 (Db6)} 25. Qg2 {1.51/13 44} Kf8 {1.26/38 106} 26. Rdf1 {1.52/14 29} Qc8 {1.17/40 77 (Ke8)} 27. h4 {1.75/19 43} h5 {2.01/34 44 } 28. f5 {1.78/20 18} exf5 {1.90/32 10} 29. gxf5 {1.81/19 14} Bxf5 {1.86/36 12} 30. Qxd5 {1.83/18 15} Rd7 {2.08/36 24 (Ld3)} 31. Qg2 {2.16/15 67} Rc7 {2.44/37 67} 32. Nd2 {2.16/15 41} Kg8 {2.27/36 48 (Ld3)} 33. Rf4 {2.16/14 58 (Tf2)} Kh7 {2.11/30 8} 34. Ne4 {2.13/15 65} Bxe4 {2.16/36 14} 35. Qxe4 {2.12/14 0} Re8 { 2.15/38 26 (Db7)} 36. Rgf1 {2.09/11 80 (Tg5)} Kg8 {1.61/35 13 (De6)} 37. R4f2 { 2.05/11 51 (Dc2)} Qb7 {1.59/35 37} 38. Qc2 {2.02/11 16} Qc6 {1.58/37 7} 39. Qc1 {2.02/11 35} Rd7 {1.73/41 65 (De4)} 40. Bh6 {2.08/12 27} Bh8 {1.73/41 9 (De4)} 41. Rg1 {2.13/10 46} Qd5 {1.73/42 10 (Tb7)} 42. Qc2 {2.14/10 28} Kh7 {1.73/43 10} 43. Bc1 {2.05/11 37} Bg7 {1.73/45 13} 44. Qxa4 {2.03/11 24} Re6 {1.73/45 12 } 45. Qc2 {2.02/14 16 (Lg5)} Rb7 {1.73/42 13} 46. Re2 {2.06/14 21 (Tgf1)} Kh8 { 1.73/40 21 (Lf8)} 47. Qe4 {2.12/10 44 (Teg2)} Qxe4 {2.02/36 29 (Db5)} 48. Rxe4 {2.40/12 22} Kh7 {2.19/35 15} 49. Bf4 {2.45/14 17 (Ka2)} Rd7 {1.69/28 7} 50. Ka2 {2.54/14 19 (Kb1)} f6 {1.87/33 19} 51. Rge1 {2.58/14 11} fxe5 {1.97/33 28} 52. dxe5 {2.64/13 27 (Lg3)} Rc7 {2.02/31 9} 53. Rd1 {2.65/12 11 (Lg3)} Bf8 { 2.73/32 58} 54. Rdd4 {2.70/15 29} Be7 {2.89/31 23} 55. Bh2 {2.76/16 19} g5 { 2.71/31 12} 56. hxg5 {2.78/15 12} Bxg5 {3.08/30 23} 57. Rxc4 {2.87/14 21} Rxc4 {3.20/27 10} 58. Rxc4 {2.84/13 10} Kg6 {3.40/28 13} 59. b4 {2.87/12 15} Kf5 { 3.50/27 10 (h4)} 60. Kb3 {3.17/11 31} Rg6 {3.68/26 10 (h4)} 61. Rd4 {3.45/10 30 (Tc7)} Be7 {3.90/24 10} 62. Rd2 {3.57/10 16} Bh4 {4.18/27 10 (h4)} 63. a4 { 3.91/9 28} Be1 {4.49/27 10 (Le7)} 64. Re2 {5.56/9 12 (Td1)} Bh4 {4.50/30 3} 65. a5 {4.67/9 23 (Td2)} Ke6 {4.71/28 17 (Le7)} 66. a6 {4.76/8 12 (Td2)} Rg7 { 5.23/26 10 (Le7)} 67. c4 {4.72/8 16 (b5)} Rd7 {5.78/24 10 (Tg4)} 68. c5 { 5.72/7 10 (Tg2)} Be7 {7.03/26 10 (Td4)} 69. Kc4 {6.96/7 9 (Tc2)} Rd1 {6.12/23 2 } 70. Kb5 {5.88/8 14 (Tc2)} h4 {7.19/27 18 (Tb1)} 71. Rb2 {5.41/8 8 (Tg2)} Bd8 {7.53/27 10 (Ta1)} 72. Kc6 {6.23/7 10} Rd7 {8.25/25 10 (Le7)} 73. Rg2 {7.20/8 12} 1-0

Fat Fritz se da cuenta en seguida cuáles son las amenazas a la hora de cerrar la posición y vislumbra los problemas de las negras por falta de espacio. Fat Fritz se decide a optar por una posición ligeramente desfavorable, pero aún así mantiene las tablas con mucha maña. 

[Event "Rapid match 20m+10s"] [Site ""] [Date "2019.10.24"] [Round "20"] [White "Stockfish 10 64 POPCNT"] [Black "Fat Fritz"] [Result "1/2-1/2"] [ECO "B04"] [Annotator "Elshan"] [PlyCount "289"] [EventDate "2019.??.??"] [TimeControl "1200+10"] 1. e4 Nf6 2. e5 Nd5 3. d4 d6 4. Nf3 {Last book move.} dxe5 {0.54/15 16} 5. Nxe5 {1.00/31 64 (c4)} c6 {0.52/14 31} 6. Be2 {1.05/29 17 (Sf3)} Bf5 {0.55/15 25 (Sd7)} 7. O-O {0.97/28 27} Nd7 {0.55/16 19} 8. Nf3 {0.95/33 43} e6 {0.54/15 26 (h6)} 9. c4 {1.03/30 13} N5f6 {0.54/14 12} 10. Nh4 {0.84/35 136} Bg6 {0.53/14 37 (Lxb1)} 11. Nc3 {0.85/29 73} Bd6 {0.54/14 37} 12. f4 {0.89/29 43 (c5)} Ne4 { 0.29/14 54 (Lf5)} 13. Nxg6 {1.01/28 9 (g3)} Nxc3 {0.22/13 38} 14. bxc3 { 0.91/29 19} hxg6 {0.21/12 14} 15. g3 {0.91/31 28} O-O {0.21/11 47 (Da5)} 16. Be3 {0.98/30 29 (a4)} c5 {0.13/10 50 (b6)} 17. Qd3 {0.85/30 42} Qc7 {0.15/11 75 (Tc8)} 18. Bf2 {0.95/31 16 (a4)} Rfd8 {0.18/10 46 (Tac8)} 19. Qf3 {1.02/31 42} b6 {0.23/10 32 (Tac8)} 20. a4 {0.89/32 61} Rac8 {0.20/12 21} 21. Kg2 { 0.85/32 12 (Tfb1)} f5 {0.24/11 30 (Le7)} 22. Bd3 {0.67/33 88 (Tab1)} cxd4 { 0.23/14 39 (Sf6)} 23. cxd4 {0.69/30 16} Bb4 {0.22/19 9} 24. Rfc1 {0.79/34 103 (Tab1)} Nf6 {0.06/11 43} 25. Rc2 {0.69/32 31} Kh7 {0.05/17 62 (Dd7)} 26. Rb1 { 0.68/31 43} a5 {0.05/23 9} 27. Rbc1 {0.68/34 48 (c5)} Qd7 {0.05/14 40} 28. Re2 {0.68/35 10} Ng4 {0.10/15 28 (Te8)} 29. Bg1 {0.82/28 11} Nf6 {0.10/14 11} 30. Bf2 {0.68/35 62 (h3)} Ng4 {0.06/14 60 (Te8)} 31. Bg1 {0.55/31 19} Nf6 {0.08/15 14} 32. Kh1 {0.68/34 65} Qxa4 {0.00/18 41 (Tc7)} 33. Rxe6 {0.00/33 25} Rd6 { 0.00/23 0 (b5)} 34. Rxd6 {0.31/31 26 (Te5)} Bxd6 {-0.04/24 56} 35. Qf1 { 0.39/35 38} Ba3 {-0.04/30 27 (Dc6+)} 36. Ra1 {0.94/28 11 (Tb1)} Qb4 {-0.04/18 91 (Dc6+)} 37. Rb1 {0.13/33 62} Qc3 {-0.04/24 0 (Dd6)} 38. Rxb6 {0.00/35 27} Re8 {-0.04/21 0} 39. Be2 {0.00/38 9} Bc1 {-0.03/22 109} 40. c5 {0.00/42 21} a4 {-0.03/22 0 (Le3)} 41. Rb1 {0.09/34 13} Be3 {-0.03/21 6} 42. Bb5 {0.09/38 11} Rd8 {-0.02/20 20 (Dxd4)} 43. Qc4 {0.00/42 29 (Dd3)} Qd2 {-0.02/19 49} 44. Qd3 { 0.00/42 10} Qxd3 {-0.01/20 11} 45. Bxd3 {0.00/44 31} Bxd4 {-0.02/18 23} 46. Ba6 {0.00/45 10 (Lc4)} a3 {-0.06/17 64} 47. c6 {0.00/44 11} a2 {-0.03/18 56} 48. Rf1 {0.00/46 10} Ne8 {-0.03/18 7} 49. Bxd4 {0.00/47 12} Rxd4 {-0.02/17 4} 50. Ra1 {0.00/48 11} Ra4 {-0.01/16 22} 51. Be2 {0.00/49 11} Nc7 {-0.01/16 13 (Kh6)} 52. h4 {0.00/45 10 (Ld1)} Kh6 {-0.08/12 83} 53. Kg2 {0.00/43 11 (Lf3)} Nd5 { -0.10/14 19 (Kh7)} 54. Kh2 {0.00/44 17 (Kf2)} Kh7 {-0.13/13 18} 55. Kh3 { 0.00/48 12} Ra3 {-0.15/14 14 (Kh6)} 56. c7 {0.00/47 12} Rc3 {-0.16/13 11} 57. Ba6 {0.00/49 9 (Txa2)} Nxf4+ {-0.09/14 48} 58. Kh2 {0.00/1 0} Rc2+ {-0.11/20 0 (Txc7)} 59. Kh1 {0.00/49 20 (Kg1)} Rxc7 {-0.14/17 13} 60. gxf4 {0.00/50 7} Rc2 {-0.12/16 6} 61. Bd3 {0.00/54 29} Rb2 {-0.11/14 10} 62. Kg1 {0.00/55 13} Kh8 { -0.09/14 32 (Tb3)} 63. Kf1 {0.00/48 19 (Kh1)} Rh2 {-0.08/13 18} 64. Kg1 { 0.00/49 40 (Ke1)} Rb2 {-0.09/13 9} 65. Kf1 {0.00/52 7} Kh7 {-0.06/12 9} 66. Ke1 {0.00/51 50 (Kg1)} Kh6 {-0.09/12 15} 67. Kf1 {0.00/52 37} Rh2 {-0.06/12 13} 68. Kg1 {0.00/49 4} Rb2 {-0.05/10 9} 69. Kf1 {0.00/51 6} Rh2 {-0.04/9 13} 70. Ke1 { 0.00/52 12 (Kg1)} Rh1+ {-0.09/10 16} 71. Bf1 {0.00/47 4} Rxh4 {-0.09/11 9 (Th2) } 72. Rxa2 {0.09/35 6} Rxf4 {-0.09/9 4} 73. Ra6 {0.09/42 8 (Tf2)} Kh7 {-0.10/9 16} 74. Be2 {0.09/46 7} g5 {-0.09/10 8} 75. Bh5 {0.09/46 7} g4 {-0.08/11 10} 76. Bg6+ {0.09/47 9} Kh6 {-0.05/10 5} 77. Bxf5+ {0.09/49 14} Kg5 {-0.04/9 25 (Kh5)} 78. Be6 {0.09/43 7 (Lc8)} g3 {-0.05/8 12} 79. Bd5 {0.09/42 7} Rf5 { -0.03/7 12 (Tf2)} 80. Bg2 {0.09/43 8} Rf2 {-0.02/7 10 (g6)} 81. Ra5+ {0.09/43 9 (La8)} Kh4 {-0.03/8 11 (Tf5)} 82. Ra4+ {0.09/46 15} Kg5 {-0.01/8 9} 83. Bf1 { 0.09/45 6 (La8)} Rh2 {-0.05/7 10 (Tf4)} 84. Be2 {0.09/45 9 (Ta7)} Rh1+ { -0.09/8 12 (Th4)} 85. Kd2 {0.48/42 6} Rh4 {-0.09/8 8} 86. Ra7 {0.48/43 8 (Ta1)} g6 {-0.07/8 11} 87. Ke3 {0.58/44 8 (Lf3)} g2 {-0.05/8 10 (Tf4)} 88. Ra5+ { 0.90/42 7 (Kf2)} Kh6 {-0.04/9 11 (Kf6)} 89. Kf2 {0.91/44 6} Re4 {-0.02/8 11 (Tb4)} 90. Bf3 {0.91/47 7} Rb4 {-0.02/7 10 (Td4)} 91. Kxg2 {0.91/47 8} Kg7 { 0.00/7 10 (Tb2+)} 92. Kg3 {0.91/43 9 (Ta2)} Kf6 {0.00/6 10} 93. Bd1 {0.91/42 7 (Ta2)} Rd4 {0.00/7 10 (Tb2)} 94. Bc2 {0.96/38 6 (Ta1)} Ke7 {0.00/7 10 (Td6)} 95. Bxg6 {1.08/39 7 (Ta2)} Rd8 {0.00/6 10 (Ke6)} 96. Be4 {1.08/43 9 (Ta7+)} Rd1 {0.00/6 10 (Tf8)} 97. Kf3 {1.09/48 14 (Kf4)} Rd8 {0.00/6 10 (Ke6)} 98. Bd5 { 1.09/46 6 (Kf4)} Kf6 {0.00/6 10 (Tf8+)} 99. Kf4 {1.10/43 10} Rd6 {0.01/7 7} 100. Rc5 {1.10/46 14 (Tb5)} Rb6 {0.01/7 11} 101. Bc4 {1.10/47 14 (Tc4)} Rb4 { 0.01/7 11 (Td6)} 102. Rc6+ {1.11/40 7} Ke7 {0.05/8 5} 103. Ke5 {1.11/43 64} Kd7 {0.08/8 13} 104. Rc5 {1.11/40 35 (Ld5)} Rb6 {0.05/8 8} 105. Bb5+ {1.11/44 19 (Ld5)} Ke7 {0.04/8 13} 106. Rc7+ {1.11/42 11} Kd8 {0.03/8 5} 107. Rd7+ { 1.11/41 10} Kc8 {0.04/8 7} 108. Rd5 {1.11/31 10 (La4)} Kc7 {0.02/8 15 (Kb7)} 109. Rd7+ {1.11/40 6 (Tc5+)} Kc8 {0.03/8 10 (Kb8)} 110. Rd5 {1.11/37 6 (Lc6)} Kc7 {0.02/7 13 (Kb7)} 111. Rc5+ {1.11/48 6} Kb7 {0.03/8 9 (Kd8)} 112. Bc4 { 1.11/35 19 (Lc6+)} Rh6 {0.03/7 9} 113. Bd5+ {1.11/41 5 (Le6)} Kb6 {0.04/7 9} 114. Rc8 {1.11/43 4} Rg6 {0.04/7 12} 115. Ra8 {1.11/40 21 (Kd4)} Rh6 {0.03/7 12 } 116. Rb8+ {1.11/44 11} Kc5 {0.02/7 6} 117. Rc8+ {1.11/43 11} Kb6 {0.05/8 14} 118. Rb8+ {1.11/36 4 (Kd4)} Kc5 {0.01/7 6} 119. Rc8+ {1.11/43 16} Kb6 {0.04/7 13} 120. Be4 {1.12/45 4 (Kd4)} Rh4 {0.02/7 12 (Ka5)} 121. Kd4 {1.12/41 5} Rh6 { 0.04/7 10 (Tf4)} 122. Rb8+ {1.12/44 5} Kc7 {0.02/7 5} 123. Rb7+ {1.12/42 23} Kc8 {0.06/8 13} 124. Rf7 {1.12/40 13 (Kc5)} Kd8 {0.04/7 9 (Th4)} 125. Kd5 { 1.12/40 9 (Ke5)} Ke8 {0.03/7 10 (Th4)} 126. Ra7 {1.12/36 9 (Tb7)} Rb6 {0.04/8 13 (Kd8)} 127. Bf5 {1.12/37 11 (Ke5)} Kf8 {0.07/8 10 (Tb5+)} 128. Be6 {1.12/34 10 (Ke5)} Ke8 {0.06/8 6} 129. Bf7+ {1.11/30 11 (Ke5)} Kd8 {0.06/8 14} 130. Kc5 {1.11/30 10} Rf6 {0.07/8 8} 131. Kd5 {1.11/29 10 (La2)} Rb6 {0.05/8 6} 132. Be6 {1.10/26 10 (Kc5)} Ke8 {0.04/8 9} 133. Bg4 {1.09/25 10 (Ke5)} Kd8 {0.04/7 17 (Kf8)} 134. Rd7+ {1.02/22 10 (Ld7)} Ke8 {0.02/7 4} 135. Rh7 {1.02/21 10 (Le6)} Kd8 {0.04/7 16} 136. Be6 {0.77/18 10 (Ld7)} Ke8 {0.04/8 10 (Tb5+)} 137. Ke5 { 1.02/30 10} Kd8 {0.05/8 6} 138. Rd7+ {0.09/34 10 (Ld7)} Kc8 {0.03/8 13} 139. Ra7+ {0.09/33 3 (Kd5)} Kb8 {0.02/7 8 (Kd8)} 140. Ra5 {0.09/39 17 (Ta4)} Kc7 { 0.01/7 11} 141. Ba2 {0.00/26 5 (Tc5+)} Rb2 {0.00/7 12 (Kb8)} 142. Bc4 {0.00/41 15 (Lg8)} Rh2 {0.00/6 10 (Tc2)} 143. Rc5+ {0.00/52 4 (Ta8)} Kb6 {0.00/4 9} 144. Rb5+ {0.00/65 5 (Tc8)} Kc6 {0.00/2 10 (Kc7)} 145. Bf1 {0.00/127 0 Draw agreed.} 1/2-1/2

Precisión y conocimientos técnicos 

Aunque no es justamente típico por Fat Fritz que vaya optando por las variantes arriesgadas, también sabe aguantar este tipo de situaciones y lo hace con mucha precisión. Un problema de Leela a veces pueder ser que sin funcionar en una máquina realmente fuerte, puede pasar por alto de algunos detalles tácticos y eso puede nublarle la vista a la hora de evaluar la posición. Eso sí que es un problema más general de todas las redes neuronales artificiales, que suelen requerer un hardware especialmente potente para poder funcionar verdaderamente bien. Dicho eso, parece que Fat Fritz está en el camino de pasar ese obstáculo. En la siguiente partda, Fat Fritz maneja muy bien su rey y no entra en peligro alguno, a pesar de no haber optado por la mejor opción. 

[Event "Rapid match 20m+10s"] [Site ""] [Date "2019.10.24"] [Round "23"] [White "Fat Fritz"] [Black "Stockfish 10 64 POPCNT"] [Result "1/2-1/2"] [ECO "B09"] [Annotator "Elshan"] [SetUp "1"] [FEN "N4rk1/pp3pbp/4b1p1/8/4P3/2qB1Q1P/P1P1K1P1/1R5R b - - 0 19"] [PlyCount "48"] [EventDate "2019.??.??"] [TimeControl "1200+10"] {[#]} 19... Qc6 {0.00/39 40 [#] From this point onward, Fat Fritz demonstrates great and accurate defensive skills.} 20. Nb6 {0.22/26 65} axb6 {0.09/40 31} 21. Qe3 {0.22/31 0} Qc3 {0.00/39 14} 22. Qxb6 {0.19/32 37} Bc4 {0.00/42 21} 23. Bxc4 {0.15/32 29} Qxc4+ {0.00/45 141} 24. Kf3 {0.14/31 0} f5 {0.00/39 19 (Dc3+) } 25. e5 {0.16/20 174} Qe4+ {0.00/42 44} 26. Kf2 {0.15/22 0} Qf4+ {0.00/44 29} 27. Kg1 {0.12/23 62} Bxe5 {0.00/41 18} 28. Rd1 {0.12/22 0} Re8 {0.00/40 37} 29. Qf2 {0.12/22 0} Qa4 {0.00/40 26 (De4)} 30. h4 {0.12/16 96 (Df3)} Bb8 {0.00/42 21} 31. Re1 {0.10/19 116} Rd8 {0.00/44 38 (Tc8)} 32. Qf3 {0.09/14 50} Ba7+ { 0.00/42 14 (Dd4+)} 33. Kf1 {0.07/11 18} Rd2 {0.00/47 53 (Dc4+)} 34. Re2 { 0.09/17 54 (Db3+)} Rd1+ {0.00/45 29 (Txe2)} 35. Re1 {0.23/17 0} Qc4+ {0.00/45 24 (Db5+)} 36. Qe2 {0.05/9 33} Qf4+ {0.00/50 20} 37. Qf3 {0.03/7 23} Rxe1+ { 0.00/46 19 (Dc4+)} 38. Kxe1 {0.13/11 0} Qc1+ {0.00/51 21} 39. Qd1 {0.03/9 54 (Ke2)} Qe3+ {0.00/50 20} 40. Qe2 {0.01/7 31} Qc1+ {0.00/51 17} 41. Qd1 { 0.01/5 0} Qe3+ {0.00/52 49} 42. Qe2 {0.01/3 51} Qc1+ {0.00/58 85} 43. Qd1 { 0.00/2 0 Remis angenommen} 1/2-1/2

Una obra de arte a lo Karpov 

La verdad es que ha habido muchas partidas muy bellas en el duelo entre Fat Fritz y Stockfish. Las victorias de Stockfish 10 también han sido impresionantes. Pero como aquí estamos hablando de Fat Fritz, es obligatorio mostrar también una de las obras de arte que ha producido él. Había obtenido una ventaja posicional a tras la apertura y a continuación Fat Fritz tomó su tiemo antes de realizar que el avance por el flanco de dama es suficiente como para plantear un fantástico sacrificio. Bueno, ya lo verán ustedes mismos: 

[Event "Rapid match 20m+10s"] [Site ""] [Date "2019.10.25"] [Round "45"] [White "Fat Fritz"] [Black "Stockfish 10 64 POPCNT"] [Result "1-0"] [ECO "B90"] [Annotator "Elshan"] [PlyCount "135"] [EventDate "2019.??.??"] [TimeControl "1200+10"] 1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 {Last Book move} 6. f3 { 0.43/14 19} e5 {0.00/31 40} 7. Nb3 {0.40/16 19} Be6 {0.16/34 81 (Le7)} 8. Be3 { 0.41/15 26} Be7 {0.30/33 50 (h5)} 9. Qd2 {0.43/20 30} O-O {0.15/33 48} 10. O-O-O {0.46/24 25} Nbd7 {0.17/35 24} 11. g4 {0.47/23 18} b5 {0.05/32 8} 12. g5 {0.46/22 23} Nh5 {0.00/35 19} 13. Kb1 {0.47/21 26} Nb6 {0.00/36 41} 14. Na5 { 0.48/21 19 (Sd5)} Rc8 {0.00/37 36 (Dc7)} 15. a3 {0.51/21 58 (Sd5)} g6 {0.00/35 21 (Dc7)} 16. h4 {0.54/18 64} Qc7 {0.00/37 10} 17. Rh2 {0.51/21 32} Rfe8 { 0.00/39 18} 18. Nd5 {0.60/20 67} Nxd5 {0.00/41 18} 19. exd5 {0.58/27 0} Bd7 { 0.00/43 19} 20. Qb4 {0.44/22 104 (Lh3)} Bf5 {0.00/38 41 (Sg3)} 21. Nc6 { 0.79/15 36} Bf8 {0.00/39 28} 22. Bd3 {0.75/15 27 (Lh3)} Bxd3 {0.00/40 22} 23. Rxd3 {0.73/16 11} f5 {0.00/40 17 (Dd7)} 24. Rb3 {0.71/16 50 (Td1)} Ng7 { 0.00/39 51 (f4)} 25. Re2 {0.77/16 76 (Th1)} f4 {0.00/38 30 (Df7)} 26. Bf2 { 0.78/14 18} Qf7 {0.00/36 13 (Sf5)} 27. Qe4 {0.83/14 29 (Td2)} Nf5 {0.00/38 53} 28. Rd2 {0.85/16 22} Bg7 {0.00/35 52 (h6)} 29. Rd1 {0.94/14 40 (c4)} Nd4 { 0.00/38 16} 30. Rc3 {0.92/13 47 (Tbd3)} Rc7 {0.11/39 187 (Sf5)} 31. Rcd3 { 0.89/13 43 (a4)} Nf5 {0.00/40 19 (Tcc8)} 32. Rb3 {0.84/13 57} Rb7 {0.00/43 128 (Se7)} 33. Rb4 {0.99/10 28 (Sa5)} Rf8 {0.00/37 20} 34. Rb3 {0.96/11 23} Qd7 { 0.00/35 23 (Te8)} 35. Rc1 {0.94/12 57 (Tc3)} Re8 {0.00/36 22 (Sg3)} 36. Rb4 { 0.97/10 37 (Tg1)} Kh8 {0.00/36 41 (Tf8)} 37. Rg1 {1.07/10 25} Rc8 {0.00/36 23 (Df7)} 38. Na5 {0.80/16 44 (Th1)} Rbb8 {0.00/40 12} 39. Nc6 {0.81/22 9} Rb7 { 0.00/40 22} 40. Rc1 {0.75/22 46 (Th1)} Rf8 {0.00/38 47 (Se7)} 41. Rb3 {1.02/12 24 (Th1)} Rc7 {0.00/38 21 (Df7)} 42. Ka2 {1.04/11 34 (Dd3)} Rb7 {0.00/35 19} 43. Rg1 {1.01/11 32 (Kb1)} Rc8 {0.00/38 32 (Df7)} 44. Rc1 {1.01/12 26 (Th1)} Qf7 {0.02/37 104 [#] (Tf8)} 45. c4 {1.24/17 29} Ng3 {0.54/37 100 (bxc4)} 46. Qd3 {1.24/18 28} bxc4 {0.59/31 13} 47. Qxc4 {1.19/18 13} Rxb3 {0.51/35 21} 48. Qxb3 {1.19/14 14} Re8 {0.45/34 8 (Dd7)} 49. Bb6 {1.41/19 39} Qd7 {0.52/34 15} 50. Nd8 $3 {1.62/21 19 It is not only for the depth but the briliant idea behind this move: Black must take and then:} Rxd8 {1.80/33 48} 51. Bxd8 { 1.73/22 14} Qxd8 {3.61/32 15} 52. Qb7 {1.78/21 9} Qg8 {3.99/35 20} 53. a4 $1 { 1.86/22 21 Black's two minor pieces are rather clumsy. Black loses one way or another.} Nf5 {4.13/34 15 (Lf8)} 54. Qxa6 {2.73/14 43} Qxd5+ {4.22/33 4} 55. Qc4 {3.02/16 25} Qg8 {4.47/37 13} 56. Qxg8+ {3.19/16 17 (a5)} Kxg8 {0.45/1 0} 57. a5 {3.29/15 8} e4 {4.49/32 9} 58. a6 {3.33/14 19} Bd4 {4.34/34 6} 59. Rc4 { 3.41/13 8 Threatening Rxd4 followed by a7-a8} Bg1 {4.85/35 13} 60. Rxe4 { 3.46/12 26} Kf7 {5.07/37 22 (d5)} 61. Rxf4 {4.33/11 32} d5 {5.38/36 12} 62. Rb4 {4.62/11 17} Ke6 {5.78/37 10 (Sd6)} 63. Rb7 {4.78/11 21} Nxh4 {6.29/37 10} 64. f4 {4.77/12 10 (b4)} Ng2 {5.04/25 3} 65. Rxh7 {4.77/12 35} Nxf4 {7.18/30 18} 66. a7 {4.99/12 1 (b4)} Bxa7 {7.00/26 3} 67. Rxa7 {4.69/10 8} d4 {9.25/29 17 (Sh3)} 68. Ra5 {5.61/9 26} 1-0

Finalmente, la partida número 49, que nos brinda otro ejemplo más de lo fuertes que son las redes artificiales neuronales cuando juegan al ajedrez. 

[Event "Rapid match 20m+10s"] [Site ""] [Date "2019.10.25"] [Round "49"] [White "Fat Fritz"] [Black "Stockfish 10 64 POPCNT"] [Result "1-0"] [ECO "C02"] [Annotator "Elshan"] [PlyCount "145"] [EventDate "2019.??.??"] [TimeControl "1200+10"] 1. e4 e6 2. d4 d5 3. e5 c5 4. c3 Nc6 5. Nf3 Qb6 6. a3 c4 {Last book move.} 7. Nbd2 {0.35/14 20} Na5 {-0.25/33 77} 8. Rb1 {0.35/14 22} Bd7 {-0.17/31 15} 9. Be2 {0.37/15 31} Ne7 {-0.32/33 30 (0-0-0)} 10. h4 {0.39/14 30 (0-0)} O-O-O { -0.27/33 66} 11. h5 {0.37/16 21 (Sf1)} Kb8 {-0.25/33 29 (f6)} 12. Nf1 {0.47/13 41} h6 {-0.19/31 23} 13. Bf4 {0.49/12 31} Nb3 {-0.11/32 57 (a6)} 14. Ne3 { 0.63/12 67 (S3d2)} Ba4 {-0.04/33 23 (Ka8)} 15. Nd2 {0.70/12 32} Nc6 {0.00/31 30 (Sxd2)} 16. Nxb3 {0.70/13 35 (Lg3)} Na5 {0.00/34 72} 17. Kf1 {0.65/13 66 (Lg3)} Bxb3 {0.00/40 26 (a6)} 18. Qd2 {0.68/14 20} Ba4 {0.00/39 11} 19. Bd1 { 0.67/13 20 (De1)} Bxd1 {0.00/35 17} 20. Rxd1 {0.66/12 25} a6 {0.00/37 16 (Le7)} 21. Rh3 {0.64/10 92 (Lg3)} Be7 {0.00/37 36} 22. Kg1 {0.62/11 41 (Lg3)} Rdg8 { 0.00/35 13} 23. Bh2 {0.59/11 36 (De2)} Qd8 {0.00/35 34 (Ka7)} 24. Qe2 {0.56/10 43 (Lg3)} Ka7 {0.00/37 39} 25. f4 {0.56/11 19 (Df3)} g6 {0.00/29 16} 26. g4 { 0.62/12 24 (Dg4)} Nb3 {0.00/33 56 (Sc6)} 27. Kh1 {0.72/11 42} Qe8 {0.00/38 41 (Dd7)} 28. Qf3 {0.73/14 31} Bd8 {0.00/37 35 (Th7)} 29. hxg6 {0.77/18 34} Rxg6 { 0.09/32 31 (fxg6)} 30. f5 {1.86/13 33 (Lg3)} Rg7 {0.00/38 34 (Tgg8)} 31. f6 { 1.89/13 24 (Lf4)} Rg6 {0.97/34 66} 32. Bf4 {1.89/11 22} Bc7 {1.00/35 28} 33. Ng2 {1.95/11 53 (Kg2)} Qg8 {1.34/26 82} 34. Rh4 {1.96/11 20} Qd8 {1.82/30 158 (Dh7)} 35. Be3 {2.27/11 49 (Kh2)} Na5 {2.46/30 84 (Dg8)} 36. Rd2 {2.40/11 39 (Sf4)} Nb3 {2.44/32 17 (Sc6)} 37. Rf2 {2.57/11 39 (Td1)} Rgg8 {3.38/30 83 (Dg8) } 38. Bxh6 {2.89/10 41 (Sf4)} Qd7 {3.65/26 36 (Lb6)} 39. Be3 {3.16/9 51 (g5)} Rxh4+ {4.29/30 54 (Sa5)} 40. Nxh4 {3.37/10 28} Rh8 {4.55/29 14} 41. Rh2 { 3.57/10 27} Na5 {5.06/34 56 (Da4)} 42. g5 {3.92/9 43 (Sg2)} Nc6 {5.17/32 22} 43. Ng2 {4.05/9 36} Rg8 {5.35/32 15 (De8)} 44. Rh7 {4.21/8 49} Nd8 {5.45/31 15 (Lb6)} 45. Qd1 {4.33/8 32 (Tg7)} Qb5 {4.48/27 19 (De8)} 46. Qc2 {4.56/8 24 (De2)} Qb6 {5.14/32 58 (De8)} 47. Kg1 {5.08/8 45 (De2)} Kb8 {5.43/31 29 (Lb8)} 48. Kf1 {5.45/8 35 (De2)} Ka7 {5.47/29 15} 49. Kf2 {5.48/8 25 (Kg1)} Qc6 { 6.00/29 16 (Sc6)} 50. Nh4 {5.36/7 26} Rf8 {6.40/31 10 (De8)} 51. Nf3 {6.20/7 21 (g6)} Rg8 {6.60/29 10 (De8)} 52. Kg3 {5.99/7 26 (Sh4)} Ba5 {5.51/26 10 (De8) } 53. Bf4 {6.00/7 23 (Sh4)} Qb5 {5.56/29 10 (De8)} 54. Rh6 {5.74/7 21 (Sh4)} Rf8 {5.74/29 10 (De8)} 55. Rh7 {5.85/7 19} Rg8 {5.51/28 5} 56. Bd2 {5.44/7 18 (Sh4)} Bc7 {5.61/28 10 (De8)} 57. a4 {5.43/7 19 (Sh4)} Qc6 {5.20/24 7 (De8)} 58. Be3 {5.43/7 17 (Sh4)} Kb8 {5.66/29 18 (De8)} 59. Kg4 {5.44/7 16 (Sh4)} b5 { 5.38/24 7 (De8)} 60. axb5 {6.18/8 9} Qxb5 {6.24/28 12 (axb5)} 61. Rh2 {6.69/7 18 (Sh4)} Qe8 {6.27/28 10 (a5)} 62. Kg3 {6.81/7 15 (Dh7)} a5 {5.58/24 4 (Th8)} 63. Rh7 {5.96/7 15 (Dh7)} a4 {5.34/25 6} 64. Rh1 {6.03/7 9 (Th6)} Ba5 {5.60/28 19 (Db5)} 65. Ra1 {7.48/7 11 (Th6)} Bb6 {5.85/24 11 (Th8)} 66. Qxa4 {11.19/7 11 (Txa4)} Qxa4 {5.22/28 2} 67. Rxa4 {11.46/8 8} Kc7 {6.13/34 18 (Sc6)} 68. Ra1 {16.83/7 22} Rh8 {6.59/31 7 (Sc6)} 69. Rg1 {15.38/7 13 (g6)} Kc6 {6.30/31 8 (Kd7)} 70. Rb1 {14.77/7 11 (Tf1)} Kd7 {6.68/31 15 (Lxd4)} 71. Bf4 {14.01/7 11 (Tf1)} Ba5 {6.65/31 9 (Lxd4)} 72. Ra1 {13.33/7 11 (g6)} Bc7 {6.69/34 5 (Lxc3)} 73. Kg4 {13.55/7 11 (g6)} 1-0

Para reproducir todas las partidas de Fat Fritz vs. Stockfish 8

 

Para reproducir todas las partidas Fat Fritz vs. Stockfish 10

 

Fritz 17 saldrá a la venta el 12 de noviembre con lo cual seguiremos informando del tema de Fat Fritz y de las demás novedades en Fritz 17. 




Elshan Moradiabadi es un GM nacido y criado en Teherán (Irán) Se mudó a EE.UU. en 2012. desde entonces se ha mantenido activo en el ajedrez estadounidense. Es un monitor veterano y da clases de todos los niveles, desde principiantes a MI.
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