Getting Stockfish to find all mates-in-n How do you make Stockfish find all mates in 2 or 3 from a given position? I know I need to use Scid, but not much beyond that.

Could not be any simpler, run stockfish, turn on MultiPV option to view all variation, not the only one, then run analysis and you'll get your output, for example for all mate-in-2 I could do this:

$ stockfish
Stockfish 09-06-13 64bit by Tord Romstad, Marco Costalba and Joona Kiiski
uci
id name Stockfish 09-06-13 64bit
id author Tord Romstad, Marco Costalba and Joona Kiiski

option name Use Debug Log type check default false
option name Use Search Log type check default false
option name Search Log Filename type string default SearchLog.txt
option name Book File type string default book.bin
option name Best Book Move type check default false
option name Contempt Factor type spin default 0 min -50 max 50
option name Mobility (Middle Game) type spin default 100 min 0 max 200
option name Mobility (Endgame) type spin default 100 min 0 max 200
option name Passed Pawns (Middle Game) type spin default 100 min 0 max 200
option name Passed Pawns (Endgame) type spin default 100 min 0 max 200
option name Space type spin default 100 min 0 max 200
option name Aggressiveness type spin default 100 min 0 max 200
option name Cowardice type spin default 100 min 0 max 200
option name Min Split Depth type spin default 7 min 4 max 12
option name Max Threads per Split Point type spin default 5 min 4 max 8
option name Threads type spin default 8 min 1 max 64
option name Use Sleeping Threads type check default true
option name Hash type spin default 32 min 1 max 8192
option name Clear Hash type button
option name Ponder type check default true
option name OwnBook type check default false
option name MultiPV type spin default 1 min 1 max 500
option name Skill Level type spin default 20 min 0 max 20
option name Emergency Move Horizon type spin default 40 min 0 max 50
option name Emergency Base Time type spin default 200 min 0 max 30000
option name Emergency Move Time type spin default 70 min 0 max 5000
option name Minimum Thinking Time type spin default 20 min 0 max 5000
option name Slow Mover type spin default 100 min 10 max 1000
option name UCI_Chess960 type check default false
option name UCI_AnalyseMode type check default false
uciok
position fen 8/k1K5/2R5/8/8/8/8/8 w - - 0 1
setoption name MultiPV value 100
go depth 10
info depth 1 seldepth 3 score cp 8313 nodes 311 nps 155500 time 2 multipv 1 pv c6c1
info depth 1 seldepth 3 score cp 8313 nodes 311 nps 155500 time 2 multipv 2 pv c6c2
info depth 1 seldepth 3 score cp 8313 nodes 311 nps 155500 time 2 multipv 3 pv c6c3
info depth 1 seldepth 3 score cp 8313 nodes 311 nps 155500 time 2 multipv 4 pv c6c4
info depth 1 seldepth 3 score cp 8313 nodes 311 nps 155500 time 2 multipv 5 pv c6c5
info depth 1 seldepth 3 score cp 8313 nodes 311 nps 155500 time 2 multipv 6 pv c6b6
info depth 1 seldepth 3 score cp 8313 nodes 311 nps 155500 time 2 multipv 7 pv c6d6
info depth 1 seldepth 3 score cp 8313 nodes 311 nps 155500 time 2 multipv 8 pv c6e6
info depth 1 seldepth 3 score cp 8313 nodes 311 nps 155500 time 2 multipv 9 pv c6f6
info depth 1 seldepth 3 score cp 8313 nodes 311 nps 155500 time 2 multipv 10 pv c6g6
info depth 1 seldepth 3 score cp 8313 nodes 311 nps 155500 time 2 multipv 11 pv c6h6
info depth 1 seldepth 3 score cp 8313 nodes 311 nps 155500 time 2 multipv 12 pv c7c8
info depth 1 seldepth 3 score cp 8303 nodes 311 nps 155500 time 2 multipv 13 pv c7d6
info depth 1 seldepth 3 score cp 8303 nodes 311 nps 155500 time 2 multipv 14 pv c7d7
info depth 1 seldepth 3 score cp 8303 nodes 311 nps 155500 time 2 multipv 15 pv c7d8
info depth 1 seldepth 3 score cp 0 nodes 311 nps 155500 time 2 multipv 16 pv c6a6 a7a6
info depth 2 seldepth 3 score mate 2 nodes 989 nps 494500 time 2 multipv 1 pv c6b6 a7a8 b6a6
info depth 2 seldepth 3 score mate 2 nodes 989 nps 494500 time 2 multipv 2 pv c6d6 a7a8 d6a6
info depth 2 seldepth 3 score mate 2 nodes 989 nps 494500 time 2 multipv 3 pv c6e6 a7a8 e6a6
info depth 2 seldepth 3 score mate 2 nodes 989 nps 494500 time 2 multipv 4 pv c6f6 a7a8 f6a6
info depth 2 seldepth 3 score mate 2 nodes 989 nps 494500 time 2 multipv 5 pv c6g6 a7a8 g6a6
info depth 2 seldepth 3 score mate 2 nodes 989 nps 494500 time 2 multipv 6 pv c6h6 a7a8 h6a6
info depth 2 seldepth 3 score mate 2 nodes 989 nps 494500 time 2 multipv 7 pv c7c8 a7a8 c6a6
info depth 2 seldepth 3 score cp 8308 nodes 989 nps 494500 time 2 multipv 8 pv c6c1 a7a6
info depth 2 seldepth 3 score cp 8308 nodes 989 nps 494500 time 2 multipv 9 pv c6c2 a7a6
info depth 2 seldepth 3 score cp 8308 nodes 989 nps 494500 time 2 multipv 10 pv c6c3 a7a6
info depth 2 seldepth 3 score cp 8308 nodes 989 nps 494500 time 2 multipv 11 pv c6c4 a7a6
info depth 2 seldepth 3 score cp 8308 nodes 989 nps 494500 time 2 multipv 12 pv c6c5 a7a6
info depth 2 seldepth 3 score cp 8303 nodes 989 nps 494500 time 2 multipv 13 pv c7d6 a7b7
info depth 2 seldepth 3 score cp 8303 nodes 989 nps 494500 time 2 multipv 14 pv c7d7 a7b7
info depth 2 seldepth 3 score cp 8303 nodes 989 nps 494500 time 2 multipv 15 pv c7d8 a7b7
info depth 2 seldepth 3 score cp 0 nodes 989 nps 494500 time 2 multipv 16 pv c6a6 a7a6
info depth 3 seldepth 4 score mate 2 nodes 1858 nps 929000 time 2 multipv 1 pv c6b6 a7a8 b6a6
info depth 3 seldepth 4 score mate 2 nodes 1858 nps 929000 time 2 multipv 2 pv c6d6 a7a8 d6a6
info depth 3 seldepth 4 score mate 2 nodes 1858 nps 929000 time 2 multipv 3 pv c6e6 a7a8 e6a6
info depth 3 seldepth 4 score mate 2 nodes 1858 nps 929000 time 2 multipv 4 pv c6f6 a7a8 f6a6
info depth 3 seldepth 4 score mate 2 nodes 1858 nps 929000 time 2 multipv 5 pv c6g6 a7a8 g6a6
info depth 3 seldepth 4 score mate 2 nodes 1858 nps 929000 time 2 multipv 6 pv c6h6 a7a8 h6a6
info depth 3 seldepth 4 score mate 2 nodes 1858 nps 929000 time 2 multipv 7 pv c7c8 a7a8 c6a6
info depth 3 seldepth 4 score cp 8308 nodes 1858 nps 929000 time 2 multipv 8 pv c6c1 a7a6 c1b1
info depth 3 seldepth 4 score cp 8308 nodes 1858 nps 929000 time 2 multipv 9 pv c6c2 a7a6 c2c1
info depth 3 seldepth 4 score cp 8308 nodes 1858 nps 929000 time 2 multipv 10 pv c6c3 a7a6 c3c1
info depth 3 seldepth 4 score cp 8308 nodes 1858 nps 929000 time 2 multipv 11 pv c6c4 a7a6 c4c1
info depth 3 seldepth 4 score cp 8308 nodes 1858 nps 929000 time 2 multipv 12 pv c6c5 a7a6 c5c1
info depth 3 seldepth 4 score cp 8303 nodes 1858 nps 929000 time 2 multipv 13 pv c7d6 a7b7 c6c1
info depth 3 seldepth 4 score cp 8303 nodes 1858 nps 929000 time 2 multipv 14 pv c7d7 a7b7 c6c1
info depth 3 seldepth 4 score cp 8303 nodes 1858 nps 929000 time 2 multipv 15 pv c7d8 a7b7 c6c1
info depth 3 seldepth 4 score cp 0 nodes 1858 nps 929000 time 2 multipv 16 pv c6a6 a7a6
info depth 4 seldepth 4 score mate 2 nodes 3184 nps 1061333 time 3 multipv 1 pv c6b6 a7a8 b6a6
info depth 4 seldepth 4 score mate 2 nodes 3184 nps 1061333 time 3 multipv 2 pv c6d6 a7a8 d6a6
info depth 4 seldepth 4 score mate 2 nodes 3184 nps 1061333 time 3 multipv 3 pv c6e6 a7a8 e6a6
info depth 4 seldepth 4 score mate 2 nodes 3184 nps 1061333 time 3 multipv 4 pv c6f6 a7a8 f6a6
info depth 4 seldepth 4 score mate 2 nodes 3184 nps 1061333 time 3 multipv 5 pv c6g6 a7a8 g6a6
info depth 4 seldepth 4 score mate 2 nodes 3184 nps 1061333 time 3 multipv 6 pv c6h6 a7a8 h6a6
info depth 4 seldepth 4 score mate 2 nodes 3184 nps 1061333 time 3 multipv 7 pv c7c8 a7a8 c6a6
info depth 4 seldepth 4 score mate 3 nodes 3184 nps 1061333 time 3 multipv 8 pv c6c1 a7a6 c1c5 a6a7 c5a5
info depth 4 seldepth 4 score mate 3 nodes 3184 nps 1061333 time 3 multipv 9 pv c6c2 a7a6 c2c5 a6a7 c5a5
info depth 4 seldepth 4 score mate 3 nodes 3184 nps 1061333 time 3 multipv 10 pv c6c3 a7a6 c3c5 a6a7 c5a5
info depth 4 seldepth 4 score mate 3 nodes 3184 nps 1061333 time 3 multipv 11 pv c6c4 a7a6 c4c5 a6a7 c5a5
info depth 4 seldepth 4 score mate 3 nodes 3184 nps 1061333 time 3 multipv 12 pv c6c5 a7a6 c5d5 a6a7 d5a5
info depth 4 seldepth 4 score cp 8303 nodes 3184 nps 1061333 time 3 multipv 13 pv c7d6 a7b7 d6c5 b7b8
info depth 4 seldepth 4 score cp 8303 nodes 3184 nps 1061333 time 3 multipv 14 pv c7d7 a7b7 c6d6 b7a7
info depth 4 seldepth 4 score cp 8303 nodes 3184 nps 1061333 time 3 multipv 15 pv c7d8 a7b7 c6d6 b7a7
info depth 4 seldepth 4 score cp 0 nodes 3184 nps 1061333 time 3 multipv 16 pv c6a6 a7a6
info depth 5 seldepth 7 score mate 2 nodes 4801 nps 1200250 time 4 multipv 1 pv c6b6 a7a8 b6a6
info depth 5 seldepth 7 score mate 2 nodes 4801 nps 1200250 time 4 multipv 2 pv c6d6 a7a8 d6a6
info depth 5 seldepth 7 score mate 2 nodes 4801 nps 1200250 time 4 multipv 3 pv c6e6 a7a8 e6a6
info depth 5 seldepth 7 score mate 2 nodes 4801 nps 1200250 time 4 multipv 4 pv c6f6 a7a8 f6a6
info depth 5 seldepth 7 score mate 2 nodes 4801 nps 1200250 time 4 multipv 5 pv c6g6 a7a8 g6a6
info depth 5 seldepth 7 score mate 2 nodes 4801 nps 1200250 time 4 multipv 6 pv c6h6 a7a8 h6a6
info depth 5 seldepth 7 score mate 2 nodes 4801 nps 1200250 time 4 multipv 7 pv c7c8 a7a8 c6a6
info depth 5 seldepth 7 score mate 3 nodes 4801 nps 1200250 time 4 multipv 8 pv c6c1 a7a6 c1c5 a6a7 c5a5
info depth 5 seldepth 7 score mate 3 nodes 4801 nps 1200250 time 4 multipv 9 pv c6c2 a7a6 c2c5 a6a7 c5a5
info depth 5 seldepth 7 score mate 3 nodes 4801 nps 1200250 time 4 multipv 10 pv c6c3 a7a6 c3c5 a6a7 c5a5
info depth 5 seldepth 7 score mate 3 nodes 4801 nps 1200250 time 4 multipv 11 pv c6c4 a7a6 c4c5 a6a7 c5a5
info depth 5 seldepth 7 score mate 3 nodes 4801 nps 1200250 time 4 multipv 12 pv c6c5 a7a6 c5d5 a6a7 d5a5
info depth 5 seldepth 7 score cp 8313 nodes 4801 nps 1200250 time 4 multipv 13 pv c7d6 a7b7 d6c5 b7b8 c5b6
info depth 5 seldepth 7 score cp 8313 nodes 4801 nps 1200250 time 4 multipv 14 pv c7d7 a7b7 c6d6 b7b8 d6a6
info depth 5 seldepth 7 score cp 8313 nodes 4801 nps 1200250 time 4 multipv 15 pv c7d8 a7b7 c6d6 b7b8 d6a6
info depth 5 seldepth 7 score cp 0 nodes 4801 nps 1200250 time 4 multipv 16 pv c6a6 a7a6
info depth 6 seldepth 7 score mate 2 nodes 6642 nps 1660500 time 4 multipv 1 pv c6b6 a7a8 b6a6
info depth 6 seldepth 7 score mate 2 nodes 6642 nps 1660500 time 4 multipv 2 pv c6d6 a7a8 d6a6
info depth 6 seldepth 7 score mate 2 nodes 6642 nps 1660500 time 4 multipv 3 pv c6e6 a7a8 e6a6
info depth 6 seldepth 7 score mate 2 nodes 6642 nps 1660500 time 4 multipv 4 pv c6f6 a7a8 f6a6
info depth 6 seldepth 7 score mate 2 nodes 6642 nps 1660500 time 4 multipv 5 pv c6g6 a7a8 g6a6
info depth 6 seldepth 7 score mate 2 nodes 6642 nps 1660500 time 4 multipv 6 pv c6h6 a7a8 h6a6
info depth 6 seldepth 7 score mate 2 nodes 6642 nps 1660500 time 4 multipv 7 pv c7c8 a7a8 c6a6
info depth 6 seldepth 7 score mate 3 nodes 6642 nps 1660500 time 4 multipv 8 pv c6c1 a7a6 c1c5 a6a7 c5a5
info depth 6 seldepth 7 score mate 3 nodes 6642 nps 1660500 time 4 multipv 9 pv c6c2 a7a6 c2c5 a6a7 c5a5
info depth 6 seldepth 7 score mate 3 nodes 6642 nps 1660500 time 4 multipv 10 pv c6c3 a7a6 c3c5 a6a7 c5a5
info depth 6 seldepth 7 score mate 3 nodes 6642 nps 1660500 time 4 multipv 11 pv c6c4 a7a6 c4c5 a6a7 c5a5
info depth 6 seldepth 7 score mate 3 nodes 6642 nps 1660500 time 4 multipv 12 pv c6c5 a7a6 c5d5 a6a7 d5a5
info depth 6 seldepth 7 score cp 8308 nodes 6642 nps 1660500 time 4 multipv 13 pv c7d6 a7b7 d6c5 b7a7 c6b6 a7a8
info depth 6 seldepth 7 score cp 8308 nodes 6642 nps 1660500 time 4 multipv 14 pv c7d7 a7b7 c6d6 b7b8 d7c6 b8c8
info depth 6 seldepth 7 score cp 8308 nodes 6642 nps 1660500 time 4 multipv 15 pv c7d8 a7b7 c6d6 b7b8 d6d7 b8a8
info depth 6 seldepth 7 score cp 0 nodes 6642 nps 1660500 time 4 multipv 16 pv c6a6 a7a6
info depth 7 seldepth 8 score mate 2 nodes 9342 nps 1557000 time 6 multipv 1 pv c6b6 a7a8 b6a6
info depth 7 seldepth 8 score mate 2 nodes 9342 nps 1557000 time 6 multipv 2 pv c6d6 a7a8 d6a6
info depth 7 seldepth 8 score mate 2 nodes 9342 nps 1557000 time 6 multipv 3 pv c6e6 a7a8 e6a6
info depth 7 seldepth 8 score mate 2 nodes 9342 nps 1557000 time 6 multipv 4 pv c6f6 a7a8 f6a6
info depth 7 seldepth 8 score mate 2 nodes 9342 nps 1557000 time 6 multipv 5 pv c6g6 a7a8 g6a6
info depth 7 seldepth 8 score mate 2 nodes 9342 nps 1557000 time 6 multipv 6 pv c6h6 a7a8 h6a6
info depth 7 seldepth 8 score mate 2 nodes 9342 nps 1557000 time 6 multipv 7 pv c7c8 a7a8 c6a6
info depth 7 seldepth 8 score mate 3 nodes 9342 nps 1557000 time 6 multipv 8 pv c6c1 a7a6 c1c5 a6a7 c5a5
info depth 7 seldepth 8 score mate 3 nodes 9342 nps 1557000 time 6 multipv 9 pv c6c2 a7a6 c2c5 a6a7 c5a5
info depth 7 seldepth 8 score mate 3 nodes 9342 nps 1557000 time 6 multipv 10 pv c6c3 a7a6 c3c5 a6a7 c5a5
info depth 7 seldepth 8 score mate 3 nodes 9342 nps 1557000 time 6 multipv 11 pv c6c4 a7a6 c4c5 a6a7 c5a5
info depth 7 seldepth 8 score mate 3 nodes 9342 nps 1557000 time 6 multipv 12 pv c6c5 a7a6 c5d5 a6a7 d5a5
info depth 7 seldepth 8 score cp 8318 nodes 9342 nps 1557000 time 6 multipv 13 pv c7d8 a7b7 c6d6 b7b8 d6d7 b8a8 d8c7
info depth 7 seldepth 8 score cp 8313 nodes 9342 nps 1557000 time 6 multipv 14 pv c7d6 a7b7 d6c5 b7a8 c5b6 a8b8 c6c7
info depth 7 seldepth 8 score cp 8313 nodes 9342 nps 1557000 time 6 multipv 15 pv c7d7 a7b7 c6d6 b7b8 d6b6 b8a8 d7c7 a8a7
info depth 7 seldepth 8 score cp 0 nodes 9342 nps 1557000 time 6 multipv 16 pv c6a6 a7a6
info depth 8 seldepth 11 score mate 2 nodes 11643 nps 1455375 time 8 multipv 1 pv c6b6 a7a8 b6a6
info depth 8 seldepth 11 score mate 2 nodes 11643 nps 1455375 time 8 multipv 2 pv c6d6 a7a8 d6a6
info depth 8 seldepth 11 score mate 2 nodes 11643 nps 1455375 time 8 multipv 3 pv c6e6 a7a8 e6a6
info depth 8 seldepth 11 score mate 2 nodes 11643 nps 1455375 time 8 multipv 4 pv c6f6 a7a8 f6a6
info depth 8 seldepth 11 score mate 2 nodes 11643 nps 1455375 time 8 multipv 5 pv c6g6 a7a8 g6a6
info depth 8 seldepth 11 score mate 2 nodes 11643 nps 1455375 time 8 multipv 6 pv c6h6 a7a8 h6a6
info depth 8 seldepth 11 score mate 2 nodes 11643 nps 1455375 time 8 multipv 7 pv c7c8 a7a8 c6a6
info depth 8 seldepth 11 score mate 3 nodes 11643 nps 1455375 time 8 multipv 8 pv c6c1 a7a6 c1c5 a6a7 c5a5
info depth 8 seldepth 11 score mate 3 nodes 11643 nps 1455375 time 8 multipv 9 pv c6c2 a7a6 c2c5 a6a7 c5a5
info depth 8 seldepth 11 score mate 3 nodes 11643 nps 1455375 time 8 multipv 10 pv c6c3 a7a6 c3c5 a6a7 c5a5
info depth 8 seldepth 11 score mate 3 nodes 11643 nps 1455375 time 8 multipv 11 pv c6c4 a7a6 c4c5 a6a7 c5a5
info depth 8 seldepth 11 score mate 3 nodes 11643 nps 1455375 time 8 multipv 12 pv c6c5 a7a6 c5d5 a6a7 d5a5
info depth 8 seldepth 11 score mate 6 nodes 11643 nps 1455375 time 8 multipv 13 pv c7d8 a7b7 c6d6 b7b8 d6b6 b8a8 d8c8 a8a7 c8c7 a7a8 b6a6
info depth 8 seldepth 11 score mate 6 nodes 11643 nps 1455375 time 8 multipv 14 pv c7d6 a7b7 d6c5 b7a7 c6c7 a7a8 c5b5 a8b8 b5b6 b8a8 c7c8
info depth 8 seldepth 11 score mate 6 nodes 11643 nps 1455375 time 8 multipv 15 pv c7d7 a7b7 c6d6 b7b8 d6b6 b8a8 d7c7 a8a7 b6d6 a7a8 d6a6
info depth 8 seldepth 11 score cp 0 nodes 11643 nps 1455375 time 8 multipv 16 pv c6a6 a7a6
info depth 9 seldepth 11 score mate 2 nodes 13599 nps 1359900 time 10 multipv 1 pv c6b6 a7a8 b6a6
info depth 9 seldepth 11 score mate 2 nodes 13599 nps 1359900 time 10 multipv 2 pv c6d6 a7a8 d6a6
info depth 9 seldepth 11 score mate 2 nodes 13599 nps 1359900 time 10 multipv 3 pv c6e6 a7a8 e6a6
info depth 9 seldepth 11 score mate 2 nodes 13599 nps 1359900 time 10 multipv 4 pv c6f6 a7a8 f6a6
info depth 9 seldepth 11 score mate 2 nodes 13599 nps 1359900 time 10 multipv 5 pv c6g6 a7a8 g6a6
info depth 9 seldepth 11 score mate 2 nodes 13599 nps 1359900 time 10 multipv 6 pv c6h6 a7a8 h6a6
info depth 9 seldepth 11 score mate 2 nodes 13599 nps 1359900 time 10 multipv 7 pv c7c8 a7a8 c6a6
info depth 9 seldepth 11 score mate 3 nodes 13599 nps 1359900 time 10 multipv 8 pv c6c1 a7a6 c1c5 a6a7 c5a5
info depth 9 seldepth 11 score mate 3 nodes 13599 nps 1359900 time 10 multipv 9 pv c6c2 a7a6 c2c5 a6a7 c5a5
info depth 9 seldepth 11 score mate 3 nodes 13599 nps 1359900 time 10 multipv 10 pv c6c3 a7a6 c3c5 a6a7 c5a5
info depth 9 seldepth 11 score mate 3 nodes 13599 nps 1359900 time 10 multipv 11 pv c6c4 a7a6 c4c5 a6a7 c5a5
info depth 9 seldepth 11 score mate 3 nodes 13599 nps 1359900 time 10 multipv 12 pv c6c5 a7a6 c5d5 a6a7 d5a5
info depth 9 seldepth 11 score mate 6 nodes 13599 nps 1359900 time 10 multipv 13 pv c7d8 a7b7 c6d6 b7b8 d6b6 b8a8 d8c8 a8a7 c8c7 a7a8 b6a6
info depth 9 seldepth 11 score mate 6 nodes 13599 nps 1359900 time 10 multipv 14 pv c7d6 a7b7 d6c5 b7a7 c6c7 a7a8 c5b5 a8b8 b5b6 b8a8 c7c8
info depth 9 seldepth 11 score mate 6 nodes 13599 nps 1359900 time 10 multipv 15 pv c7d7 a7b7 c6d6 b7b8 d6b6 b8a8 d7c7 a8a7 b6d6 a7a8 d6a6
info depth 9 seldepth 11 score cp 0 nodes 13599 nps 1359900 time 10 multipv 16 pv c6a6 a7a6
info depth 10 seldepth 12 score mate 2 nodes 15888 nps 1324000 time 12 multipv 1 pv c6b6 a7a8 b6a6
info depth 10 seldepth 12 score mate 2 nodes 15888 nps 1324000 time 12 multipv 2 pv c6d6 a7a8 d6a6
info depth 10 seldepth 12 score mate 2 nodes 15888 nps 1324000 time 12 multipv 3 pv c6e6 a7a8 e6a6
info depth 10 seldepth 12 score mate 2 nodes 15888 nps 1324000 time 12 multipv 4 pv c6f6 a7a8 f6a6
info depth 10 seldepth 12 score mate 2 nodes 15888 nps 1324000 time 12 multipv 5 pv c6g6 a7a8 g6a6
info depth 10 seldepth 12 score mate 2 nodes 15888 nps 1324000 time 12 multipv 6 pv c6h6 a7a8 h6a6
info depth 10 seldepth 12 score mate 2 nodes 15888 nps 1324000 time 12 multipv 7 pv c7c8 a7a8 c6a6
info depth 10 seldepth 12 score mate 3 nodes 15888 nps 1324000 time 12 multipv 8 pv c6c1 a7a6 c1c5 a6a7 c5a5
info depth 10 seldepth 12 score mate 3 nodes 15888 nps 1324000 time 12 multipv 9 pv c6c2 a7a6 c2c5 a6a7 c5a5
info depth 10 seldepth 12 score mate 3 nodes 15888 nps 1324000 time 12 multipv 10 pv c6c3 a7a6 c3c5 a6a7 c5a5
info depth 10 seldepth 12 score mate 3 nodes 15888 nps 1324000 time 12 multipv 11 pv c6c4 a7a6 c4c5 a6a7 c5a5
info depth 10 seldepth 12 score mate 3 nodes 15888 nps 1324000 time 12 multipv 12 pv c6c5 a7a6 c5d5 a6a7 d5a5
info depth 10 seldepth 12 score mate 6 nodes 15888 nps 1324000 time 12 multipv 13 pv c7d8 a7b7 c6d6 b7b8 d6b6 b8a8 d8c8 a8a7 c8c7 a7a8 b6a6
info depth 10 seldepth 12 score mate 6 nodes 15888 nps 1324000 time 12 multipv 14 pv c7d6 a7b7 d6c5 b7a7 c6c7 a7a8 c5b5 a8b8 b5b6 b8a8 c7c8
info depth 10 seldepth 12 score mate 6 nodes 15888 nps 1324000 time 12 multipv 15 pv c7d7 a7b7 c6d6 b7b8 d6b6 b8a8 d7c7 a8a7 b6d6 a7a8 d6a6
info depth 10 seldepth 12 score cp 0 nodes 15888 nps 1324000 time 12 multipv 16 pv c6a6 a7a6
info nodes 15888 time 12
bestmove c6b6 ponder a7a8


Programming chess engine I'm a Java programmer, particularly an Android developer. I'm also a good chess player. My question is where do I start if I want to program a chess engine, may or may not be from scratch. Later I want to integrate it into my Android app. Thank you for your answers!

The Chess Programming Wiki is a good place to start .  As you will quickly find out, it's a rather large and complex problem space, with many challenges (conceptual as well as actual programming).

There are plenty of open source engines out there which you could look at, to learn, or even to integrate into your engine.  I think you'll generally find that these are released under the GPL, which means you are going to have trouble making using them commercially (you would have to release your own code under GPL, if you made use of a GPL engine).

If you're aiming to have a chess engine that plays at a decent level (say, 1500+), my advice would be to try to find an existing engine to use; unless you have large amounts of free time, and you are expert in programming (preferably with some background in AI). This question on StackOverflow lists several chess engines which are released under more permissive licenses.


Novice Kid Play and Declaring Winners when Recess is Over Children at my school have become very interested in playing chess during morning break and in before/after care.  However, they only have a limited amount of time to play and must clean up...so, they cannot leave pieces on the board.  In this situation, what is the best way to declare a winner?

Is it fair to use point count for the pieces captured?

Point count is a fair way to start evaluating a chess position; even the strongest computer engines do so. I see two potential problems:

One player might have less material but an initiative, e.g. a strong kingside attack. On this level, it is not usual to sacrifice material for an initiative, so this might not be a big problem for you.
What constitutes a decisive advantage? One pawn is -usually- not enough to win an endgame, but it might be, when combined with other advantages.


Analysis of a very complicated end position - why is this move leading to a draw? I am trying to understand this position a bit better and would appreciate some help in doing so. I am black and it's my turn... (the board is flipped .. ie. black plays up and white plays down)

[FEN "8/4Kp2/4p3/4k1p1/8/8/5PP1/8 b - - 0 48"]

1...f5??  {This is what I played, although it's marked as a bad move: -0.5} (1... f6! {ok move -8}) (1... Kf5!! {best move -17}) *

I played 48...f5, which dropped my score from -17 to -0.6, basically throwing a winning situation away.

I have been reviewing this position for quite some time now but can't figure out exactly why this move was wrong. There are only 2 winning moves from here: Kf5 or f6. So what wrong with f5? (I assume something like opposition, but this is too complex for me to see)

Can someone please shed some light for me on the strategy involved? (thanks)

The reason why you lose the winning edge is, as it almost always is, because of tempi:

[fen "8/4Kp2/4p3/4k1p1/8/8/5PP1/8 b - - 0 1"]

1...f5? 2.Kf7, g4 3.g3!, Kd6 4. Kg6! (4.Kf6?, Kd5 5. Kg6, Ke4! 6.Kf6,  e5 7.Kg5, Kf3 {and black picks up the f2 pawn.})
4...Kd5 5. Kf6 {and black cannot advance without giving up a vital pawn.}

Let's look at what happens when playing ...f6 first:

[fen "8/4Kp2/4p3/4k1p1/8/8/5PP1/8 b - - 0 1"]

1...f6 2.Kf7, g4 3.g3 (3. Kg6, f5! 4. Kf7, {For 4. g3, see the variations above; it's a transposition.} 4...f4 {and white is helpless against the black pawns.})
3...Kf5 4.Ke7, e5 5.Kf7 (5.Kd6, Ke4! 6. Ke6, f5 {and white is toast.})

5...e4 6.Ke7 (6.Kg7, Kg5!) 6...Ke5! {denying the white king access to the action.} 7.Kf7, f5 8. Kg6, f4 {and black breaks through.}

So basically what happens is that ...f6 loses a tempo on purpose, to deny white the blockading idea available after ...f5. It's not easy to see immediately, but it's worth noting, as ideas like manipulating tempi in pawn endgames is the key to playing them successfully. Remember this in your next pawn endgame, as it could gain you an extra half point.

So, what about ...Kf5? It also wins:

[fen "8/4Kp2/4p3/4k1p1/8/8/5PP1/8 b - - 0 1"]

1...Kf5 2. Kxf7 (2.f3, g4!? 3. Kxf7, e5 4. Kg7 (4.Ke7, g3! 5. Kd6, e4 {and black breaks through.}) 4...Kf4! 5.Kf6, g3! 6. Kg6, Ke3! {and black picks up g2 and the victory.}) 2...e5 3.Ke7, e4! (3...g4? 4.g3!, e4 5.Kf7!, e3 6.fxe3, Ke4 7.Kf6, Kxe3? 8.Kg5, Kf3 9.Kh4 {and white wins. Oops!})
4.Kd6, g4 5.Kd5, g3 {and black wins.}

These lines aren't exhaustive, but I think that I've outlined the most important variations.

With this I hope that I've been able to show that in pawn endgames, general principles only serve to guide you. You must calculate precisely!


Tips to improve my chess I would like to get some advice on how I can get better at chess. I know that it's a lot to ask, but I would like an analysis of what I am doing wrong and in my games.  I would also like to know what I should do to practice, rather than improve the tactics or the endgame.

My Lichess ratings are as follows: 1760 for classical games, and 1900 for tactics. The latter is these days quite low but two months ago I peaked 2100. I intend to do more tactics puzzles these days until I reach again 2100.

I am quite good at my openings. Considering the last month, my average centipawn loss is 32.4, though it has usually been a bit lower (around 28). The ones belonging to middlegames and endgames are respectively, 68.2 and 35.3.

As far as endgames are concerned, I studied up to the middle of part six (corresponding to ratings:1800-1999) of the Silman’s complete endgame course, but I admit that I have not been able to test what I learned because most of the games I play are decided in the middlegame and if they reach the endgame, one side often resigns because of material imbalance. I know that I need to refresh this endgame material even if I have not used them so far very much.

Regarding calculation, I have, in my opinion, recently improved a lot as I make the point of finding candidate moves and calculate up to 10 moves deep.

I make the point of analyzing my games after I play them. First on my own, then with the computer and finally, I play the game on board again so I can see if I can use the computer‘s ideas in the game.

In general I realize that there are some  mistakes that I make that I can find on my own after playing a game but some middlegame and endgame moves are quite hard for me (not straightforward endgames such as pawn and king against lone king). Plus, I often cannot understand some mistakes (and particularly some blunders which “only” decrease my advantage by 3 points) that Stockfish detects in my games.

Here are some links to recent Lichess games of mine for you to take a look at for my requested analysis:

#1,
#2,
#3, #4
, #5
,#6

In case someone needs anything else to ask a more complete question, please do ask.

You may be able to get some help from the following tips. Not all of them apply to everybody, so you must be able to think for yourself in a critical way, picking up what works best for you!

First, forget about centipawns! I would suggest to remove computer engine assistance completely if you want to improve your game. The reason is that, more often than not, checking positions with the engine is like copying in an exam. It helps you get the right answer, but does nothing to improve your knowledge. I am not saying that engines are useless for chess training, but I am saying that it's very difficult to distinguish when they should be used. This results in often doing more harm than good (it may help you judge a bad move as bad, but for the wrong reason!)
Then, you need to work on your tactics. Puzzles and studies are great, but (of course, unassisted) analysis of your own games also plays a role here. I really doubt you can find candidates and calculate accurately up to 10 moves deep. If you really could, you would be a top-tier Grandmaster. Work on finding out what mistakes you are doing without even realizing!
Once you have a decent tactical skill (which you probably are close to having given your ratings and games), you'll need to work on your endgames and middlegame strategy. Get a book that covers topics like piece activity, central control/counterplay, weak squares, good/bad bishops, open files and so on. Don't just stick to the general tips. Instead, analyze illustrative games in depth to study how those concepts translate into practical advantage. Try to find strategical themes in your own games as well.
Last, but not least, every time you make a move, it must have a purpose! If it doesn't, then it's a bad move! If the reason is more of an excuse than an actual reason, then it's a bad move, too! (See, for instance, the ...Bxf3 mentioned in DM's answer. What were the reasons/excuses behind that trade?)

PS: If you can afford one, get a professional coach! If they are expensive on your area, go online!


How is this scenario a draw? Firstly, I'm very very bad at chess. I've known how to play for most of my life, but I've never been good, so I'm trying to get good by playing against easy computers.

I commonly end in draws with situations like the following:

3k4/8/1N6/2P2Q2/4R3/R5B1/P3K1P1/5B2 w - - 0 1

I'm really not convinced this is a real draw. I have both Rooks and my Queen left, so I should be able to box the King in easily. But maybe I'm wrong, maybe it's impossible for me to win.

So if I'm wrong, I'd like to know why. If not, why does the computer consider this a draw?

With black to move, he is not in check but he also has no legal moves. There is no square where his king can go without putting himself in check, and that would be an illegal move.

That situation is called stalemate (Wikipedia), and it is an immediate draw by the rules of the game. You've boxed him in too well.

As to why stalemate is a draw see Why is stalemate a draw? , and there are also a lot of further questions if you search the site for "stalemate".


Theoretically, why is 4. Bd3 NOT one of the best candidates in Caro-Kann? I seem to find 4. Bd3 to be one of the best choices in Caro-Kann.

[FEN ""]

1. e4 c6 2. d4 d5 3. e5 Bf5 4. Bd3

My reasoning:

White's light bishop can only develop to Be2 or Bd3. Be2 seems passive.
In Caro-Kann, Black gives up the center initially to attack it later (say by c6-c5 or other means), thus losing tempo. One of the reasons given is that Black gets the advantage of its light bishop being outside the pawn chain. By immediately challenging it, White seems to attack Black's advantage.
At move 4, Black's most active piece is its light bishop. Immediate 4. Bd3 either forces exchange thus bringing Black to square one in development; or it gets Black to lose another tempo with Bf5-Bg6.
At 4. Bf3, Black doesn't have the good option of Ne7-Nxf5, which becomes a possibility if White plays Bf3 later.

But I have never seen 4. Bd3 played in titled games.

Can the experts here help me qualitatively understand what is wrong with my reasoning?

The line usually quoted is 4.Bd3 Bxd3 5.Qxd3 Qa5+ 6. Bd2 Qa6!  If White now exchanges Queens or allows the Queens to be exchanged he already has a poor endgame structure with a bad dark-square Bishop. Otherwise he will have difficulty Castling. Certainly White is not lost, but he has given away his first-move advantage.

[FEN ""]

1. e4 c6 2. d4 d5 3. e5 Bf5 4. Bd3 Bxd3 5. Qxd3 Qa5+ 6. Bd2 Qa6!


Help with discovered checks I'm new to chess and I've found that while certain tactics come relatively easily to me(double fork), certain others are quite harder.

I've been missing out on a lot of opportunities to take advantage of discovered checks. Is there something I should be looking out for? Has anyone else faced a similar difficulty?

A Discovered Check is a "discovered" attack against a King--when a pawn or piece moves aside, to reveal a check by another piece. It's a powerful weapon, because check is given by a piece that does not have to move--and therefore, the piece that does move is free to make other threats, or even captures.

To a certain extent, you will naturally begin to see opportunities for discovered checks as you play more, because they, like all discovered attacks, are all about lines of influence. Tactics practice--all tactics, not just discovered check tactics--will help you begin to visualize these without searching for them specifically. A google search for "chess tactics" produces a decent selection of online tactics trainers.

To look for discovered checks in particular, look for pieces that would be checking the opponent's King, if not for one of your own pieces blocking the way. For example, in the diagram below:

[FEN "r2q1rk1/pp1n1ppp/3p4/2b1p3/3nPPQ1/2NB4/PPP3PP/R1B2RK1 b - - 0 1"]

Black to move.

Black's Bishop on c5 would be checking White's King, if not for the Black Knight on d4. If Black's Knight moves, it will reveal a discovered check. In fact, Black has an opportunity to win material here:

[FEN "r2q1rk1/pp1n1ppp/3p4/2b1p3/3nPPQ1/2NB4/PPP3PP/R1B2RK1 b - - 0 1"]

1...Nxc2+! 2.Kh1 Nxa1

Even though the pawn on c2 is defended by White's Bishop, the Black Knight may take it with impunity, because White must respond to the discovered check. Then Black is free to win a further exchange, Knight for Rook, after White's King runs away.

Pawns can reveal a discovered check as well, and they're sometimes much more dangerous than pieces, since they can effectively threaten anything, and even advancing at all can make them powerful weapons.

In the situation below, material is equal and there's a lot of tension on the board, but White has a devastating discovery that wins instantly...

[FEN "1k4rr/pp1n1pq1/2b2p2/2p1P3/5Q1p/2N2N2/PP3PPP/3R1RK1 w - - 0 0"]

1.exf6+!

White's pawn will take the Black Queen next turn, with no real repercussions, and he should go on to win with ease (if Black doesn't simply resign on the spot!).

One common pattern is often called a "windmill": where one piece takes advantage of a trapped King by repeatedly alternating between giving check and discovering another check. The position is from a somewhat famous game by a 13-year-old player you might have heard of:

[White "Donald Byrne"]
[Black "Bobby Fischer"]
[FEN "r3r1k1/pp3pbp/1Bp3p1/8/2bP4/Q1n2N2/P4PPP/3R1K1R w - - 0 0"]

1.Kg1 Ne2+ 2.Kf1 Nxd4+ 3.Kg1 Ne2+ 4.Kf1 Nc3+ 5.Kg1 axb6

By the end of the windmill, Black has already gained a Bishop and a pawn, and he will soon pick up the Rook on d1 as well, and go on to win handily.

A common thread in discovered check tactics is long, open lines directed at the enemy King. Because discovered checks are generally delivered from a medium or long distance, an open board and few pawns around the King make them easier to engineer. Look for pieces that could deliver check, if only some other piece or pawn was removed.

If you find a discovered check, look at all the places that the discovering piece could move: can you take free material? Make other threats that your opponent can't answer? Use a windmill to pick up many different objectives? Discovered checks are one of the most versatile threats in the game--when you get used to seeing them, your tactical levels will improve dramatically.


How do I respond to an arrogant beginner? I played a skittles game (no clocks, arbiter etc.) against a beginner who did a lot of trash talking, which I didn't rise to. Here is an example of the conversation:

  Beginner: I'm going to beat you easily!

  Bad_Bishop: I'd like to see that. I play at quite a high level. Do you want a refresher on the rules, such as en passant and castling?

  Beginner: No, I know all that already

  Bad_Bishop: OK

  Beginner: I'll take white. They always win!

  Bad_Bishop: Hmmm...

  Beginner: [Part way through the game] How do knights move again?

  Bad_Bishop: In an 'L' shape

  Beginner: [After being checkmated] OK, you won, but I took 2 pawns and a knight!

  Bad_Bishop: Hmmm. Do you want to play a different game?

My questions are, should I have handled this beginner's trash talk differently? How?

I didn't keep a scoresheet, but this is what I remember of the opening:

[FEN ""]
[White "Beginner"]
[Black "Bad_Bishop"]

  1. b3             d5
  2. Na3            e5
  3. Nb1            Bc5
  4. d4             Bxd4
  5. Kd2            Bxa1
 *

A much better way of handling it -

  Beginner: I'm going to beat you easily!

  Bad_Bishop: Of course you are.

  Beginner: I'll take white. They always win!

  Bad_Bishop: [Emphatically] Always! [pause, then with a note of doubt in your voice] Even when you are black?

  Beginner: [After being checkmated] OK, you won, but I took 2 pawns and a knight!

  Bad_Bishop: You were just so, so unlucky. [As you push the black pieces over to his side and start setting up the white pieces on your
  side] My turn as white.


Which books are suited for 1500 elo? I currently have 1500 Elo on chess.com and recently I feel like I reached a bottleneck, it seems that no matter what, it is difficult to go higher.

Considering that I want to reach 1800 which books are recommended?

Probably I am facing strategic problems, for example I can develop the rooks, by connecting them, then double them on a column, but then I don't know anymore what to do. Sometimes I can reach the 7th rank, but other times it seems simply pointless to double them.

Similarly, I develop other pieces, I can reach good positions, but still I don't know how to fully utilize them at full extent

Last, I am still having problems when the enemy launch it pawns at me on my castled side and I have to use my paws to defend.

I would recommend the Yusupov-Series, in your case the first three books (orange), called Fundamentals.

There are a lot of books out there that you would profit from reading, but the Yusupov books are more of a trainings course and I believe that you generally get out of a book in (terms of Elo) what you put into it (in terms of effort).

Doing these exercises will give you actual practical abilities instead of just illusions of understanding.


Switching from 1.e4 to 1.d4? I've only played 1.e4 as white so far (in clubs, tournaments, online, everywhere!), in the past 5 years since I learned chess. And it has been very fun, but I want to explore the dark side as well, as I do enjoy watching good positional play in GM games.

I'm sure some of you have attempted this before. I'd like to know what your experience was. Was it radically different? Did you experience withdrawal symptoms from not playing 1.e4? Did you have to learn a lot of theory just to get a playable position against well prepared Nimzos/Slavs, etc?

P.S. I know pretty much no theory in most openings beyond, say 4 or 5 moves.

I don't think 1.d4 itself really makes the game slower; you can use 1.d4 to play aggressive chess. Kasparov and Alekhine did. Likewise, you can play positional chess with 1.e4, e.g. Ruy Lopez, (especially Karpov's handling of it).

So if you want to practice positional chess you don't need to switch to 1.d4, and if you switch to 1.d4 without changing your mindset, you won't necessarily be playing positional chess.

I first tried 1.d4 after playing for about a 1 year. I was really fascinated with the Qd3 and Bc2 (or Bb1) set up and tried to drive away black knight form f6 and mate on h7, basically my whole plan revolved around that. I didn't find 1.d4 much harder to play or anything like that, but I am sure you are a stronger player than I was back then :).


Is there any obvious disadvantage of not castling in a game? The opponent has the option of castling but can I still play a solid game without castling either side? I won some games in bullet time controls but only because position was too complex and opponent lost on time. Please answer with respect to different time controls. (my rating: ~1700 on lichess)

The purpose of castling is to make the king safe. How important castling is in any particular game depends almost entirely on how safe the king is in the center. If the center is completely open (say all four central pawns have been exchanged) and many pieces are still on the board then it is very dangerous to leave the king in the center. If the center is completely closed, however, then the king may be much safer in the center.
On the other hand there are openings (Berlin Defence to the Ruy Lopez for example) where the queens come off very quickly and one side having an uncastled king is fine and confers no disadvantage.
Time controls have nothing to do with this. Having an unsafe king while your opponent's king is safe just makes your opponent's game much easier regardless of time control. You could even argue that the shorter the time control the less time you have to make plans so the easier it is for the player with the safe king because all they have to do is attack the opponent's unsafe king.


How many depth should require to get a draw decision? I've assumed about depth to take moves, it seem to be unqualified question because no precise rule to define them.

As I played with chess engine, it seem return some value with can be defined as draw position, win position, and lose position.

Win or lose still can't be defined because it should take all optimization of evaluation, but how about draw??

As chess deploy on board, it seem to believe that it still draw at first position.

Is there some fixed depth value to generalized that we can say, "It still at draw position"??

Combinational Game Theory tells us that solved games will always result in a draw if both players play optimally.  With non-solved games like chess, one can make a "draw" assumption safely in the start position : no side has played a sub-optimal move ... or any move for that matter.

There are some famous players who have postulated this rigorously but when it comes to computer evaluations,  you have to take what the engine says with a grain of salt. They are great at analytical positions but are hit-and-miss in other places including the opening.

Most engines will give White an evaluation of around +0.30 at the start (3/10ths of a pawn) but that is not significant to predict that White will be able to sustain a draw if he tries to only play for one even at Master level play.  Nor has Engine vs. Engine competition ever seen a near perfect record of draws all the time. There is too much uncertainty when dealing with complexity like the kind in chess or Go.

In short, the answer to your question really should be "no". There is no such yardstick for draw-depth nor is there any value of attempting to statistically analyze a million games for inferences.

Practically, a draw occurs at the highest levels of play when there is mutually nothing worth playing for (without incurring undue risk).


Would this clock time mode be useful at all? I want to encourage more games to be played with "thinking" chess instead of "video game" chess like in lightning and blitz.  When I play at super fast time controls, I tend to stop calculating at all and just push wood.  So my chess thought process becomes very sloppy, which makes those fast time control games pretty much useless to me in terms of improving my level.

What if there was a clock mode where a minimum time was required to be spent by a player on a move like say 10 seconds and if this rule were violated then the game would be forfeited?

I know that time delay and increment already exist, but I find there is too much temptation to gain time on the clock and move quickly.

I guess what I want is to find a clock mode that doesn't tempt me to turn off my calculating brain but where the games finish reasonably quickly.

Any thoughts on this idea?

Perhaps this could be somewhat useful in practice games, but I don't see much point in having a minimum time control in real games. Some reasons (let's assume the minimum is 10 seconds but could be any number):

sometimes you are doing forced moves (or known opening moves) where having to wait 10 seconds would be annoying
conversely, there are situations where you have to think a lot longer than 10 seconds, so here the minimum time would not help at all
you might run into the problem that you end up trying to make moves just after 10 seconds (particularly in time trouble), with the added annoyance that you now also have to keep track of when 10 seconds have passed

Overall I think that you should rather try other methods like sitting on your hands, analyzing your games with respect to time spent on moves (and relation to blunders), etc. to improve your time management. An important factor in improving your chess is also to know when to spend more time and when you can make more or less automatic moves.


What is a good playstyle for players that are not good with deep calculations? I have an opponent that knows nothing about formal chess stuff, no glossary, no openings, and so on...

And yet that opponent destroys me every time with some DEEEEEP calculating, sometimes 20 minutes long for a single move in untimed chess...

I am nowhere good enough for that. I have ADHD and lose track of what I was calculating in my head mid-move, and every time this happens, I make some stupid blunder. (Also I tend to lose due to running out of time).

Is there any obvious play style I can start to use to go around that weakness?

I have a rating of 2200, and I have similar difficulties with long calculations, but I have a good positional understanding.

My advice is:

Reduce your blunder rate by making a simple check to see whether you hang any pieces, walk into mate etc. Check out What is the most effective way of reducing blunders?
You don't need to calculate too far ahead. In my answer to How many steps can a grandmaster foresee?, I quote GM Soltis who argues that 2 1/2 moves ahead is fine for most positions
Play quiet and solid openings that don't have many forcing moves or tricky tactics. Try 1.d4, the slav-defense or the caro-kann.

This is a correspondence game I played on chess.com recently. My play was quite simple all told. I stuck to looking a few moves ahead and stuck to a plan of targeting white's isolated d-pawn:

[FEN ""]
[White ""]
[Black "Bad_Bishop"]

1. e4 c6 2. c4 d5 3. cxd5 cxd5 4. exd5 Nf6 5. Bb5+ Nbd7 6. Nc3 a6 7. Ba4? {White is out of opening theory now. Now I can focus on recovering my pawn.} b5 8. Bb3 Nb6 9. Qf3 Bb7 10. Nge2 Nbxd5 11. O-O Nxc3 {My plan from now on is to reduce material and target white's isolated d-pawn. This is quite a straightforward plan that doesn't need much calculation.} 12. Qxc3 Rc8 13. Qd4? {White should keep queens on the board, especially when my king is still in the middle. If queens were kept on, then I might have to deal with some tricky long variations.} Qxd4 14. Nxd4 Rd8 {Now I need to double rooks on the d-file to put pressure on the pawn.} 15. Nf5 e6 16. Ne3 Bc5 17. Rd1 Rd7 18. Bc2 Ke7 19. b3 Rhd8 20. d3 Bd4 21. Rb1 Nd5 {I saw an opportunity to trade minor pieces, seeing as the c3 square is weak.[%draw full,c3,red][%draw arrow,d5,c3,green]} 22. Nxd5+ Rxd5 23. Bb2 b4 {I wanted to add one more attacker onto d3, by playing ...b4, ...a5 and ...Ba6.} 24. Bxd4 Rxd4 25. Re1 a5 26. Rbd1 Ba6 27. Re3 R8d5 {I wanted to make sure that white could not start targeting my pawns with Re5.} 28. f3 f5 {If I could scare away the rook, then the d3 pawn is more likely to fall. Also, having my pawns on dark squares means white's light square bishop has no targets.} 29. Kf2 f4 30. Re4 e5 31. Rxd4 Rxd4 32. Ke2 h6 33. Kd2 g5 34. Re1 Ke6 35. Re4 Kd5 36. Ke2? {Because the d3 pawn is now pinned, I can trade rooks and invade with my king.} Rxe4+ 37. fxe4+ Kd4 38. Kd2 g4 39. Bd1? {White now cracks and loses the d3 pawn, and next the e4 pawn.} Bxd3 40. Bxg4 Bxe4  0-1


How to exploit an opponent must-win situation I am 1.5 points clear of the field, and my last-round opponent is in a must-win situation for a prize. Is there a mathematically/statistically proven way for me to take advantage of this state of affairs to maximize my own winning chances?

A sub-question of this is: Has anyone studied the phenomenon of must-win situations in sport? What was their conclusion for the side who is not must-win?

One thing is that you may adjust your opening choice, knowing that any forced draws are wins for you. For instance as white against the Najdorf, 6.Bg5 has many lines that contain forced draws, and black may be used to playing lines where he would welcome them. Now he has to avoid them and that may force him to play inferior lines.

That said -- if this makes you play openings you generally don't play, you will probably just find yourself in a sharp position that you don't know well, which is the last thing you want. And in the given tournament situation, the opponent may already be looking for openings he doesn't have any games in a database with, to avoid any special opening preparation altogether.


Are these magics wrong? I am working on my chess engine and wanted to finally implement magic bitboards to get a huge increase in performance.

Basically I was writing a method to check if a number can be used as a magic for a given attack mask. I took a look at this table: best magics and tried to verify if these can actually be used.

I tested it with the index 48 (rook on a7). I should probably say that I am working in Java and there are no unsigned values but this is not a problem because all shift-operations still work the same and the given magic for a7 is positive anyway.

So I took the mask and populated it with some random blockers.

mask:                     random blockers:

00000000                  00000000
01111110                  00110010
10000000                  10000000
10000000                  10000000
10000000                  10000000
10000000                  00000000
10000000                  00000000
00000000                  00000000

I then took the magic number (0x48FFFE99FECFAA00) and took the random blockers bitboard and multiplied them. the result and the shifted result looks like this:

result                    shifted

00000111                  00000000
00011110                  00000000
10011110                  00000000
01010101                  00000000
00000000                  00000000
00000000                  00000000
00000000                  11100000
00000000                  11000000

The problem here is that the amount of bits does not equal the one of the random blockers which is a problem because the bits in shifted result must be the same as the amount of bits in the random blockers bitboard. Also different random blockers inputs resulted in the same output.

  Can somebody verify this? Where did I go wrong?

  Also I was wondering how long it takes to generate the magic numbers.
  My code was running for a few seconds and did not find a single one (I
  checked about one thousand). What is the density of valid magics?
  1/1000 ? 1/10000000?

  My last question is: Why are people trying to reduce their tables sizes of magics? I keep seeing this and people seem to have a real battle about who can go below x kByte. Is there a specific reason for this?

EDIT:

I found the problem with the magics. I compared the shifted result and they were the same for some blockers. but these had the same actual attack set.
I am very happy for any kind of help!

I think you're misunderstanding something here based on the way you formulated your question.  Multiplying the blockers by the magic and the shifting does not give you the attack set.  What it gives you is an index by which you can lookup the attack set in a pre-computed array.  The shifted product is a key, not a bitboard as you displayed it
It is possible (and desireable) for multiple blocker sets to result in the same index and therefore have the same attack map.  Consider a rook on A1.  The attack set will be the same if there is a blocker on B1, blockers on B1 and C1, blockers on B1 and C1 and D1.
As for how long it takes to generate the magics themselves, that depends on your hardware and on the speed of your algorithm.  I would say that only being able to test a thousand in a few seconds indicates a serious performance issue in your code.  I feel like stockfish claims to be able to generate them all in a second or so.
Finally, the benefit of findind a "better" magic is what you said.  It reduces the size of the pre-computed array.  Lowering the memory footprint of an engine makes it more efficient in terms of cpu cache hits vs memory lookups.


When to decide King or Queen side castling? How do you decide to castle on king side or on queen side? i know king side is castling is the quicker than queen side with just 4 steps.

Does queen side castling favours more on attack, than compared to king side (defense)??

If pawns are more advanced on one side, or there is a material inequality to one side of your opponents pieces, castle opposite the majority of attack.

Typically, king side becomes favored, probably in part because of the property of castling you noted:  that it's quicker to king side castle.  Well, that and the King isn't as close to the center with King
 side castling.

Queen side castling is a bit easier to attack from however due to the imabalance of position (ie typically the other king is castled on its' king side).


How to improve time control/management? Personally, I find my biggest weakness to be time control/management.  I usually end up moving very fast with a lot of time left on the board or move to slow with a little time left on the board.  I am a little impatient so this probably has some connection with the speed in which I move, but I was curious as to how someone can improve their time control/management?

I'd nominate all of NM Dan Heisman's famous Novice Nook articles on Time Management (go to the link and search by subject). The *Two Move triggers* article is pretty insightful and most applicable to your posted question.

In addition, the best way to learn how to manage time is to make "time taken" a part of your post-mortem review.  In other words, don't just write down your moves, also write down how much clock you've burned per move and when reviewing the game later, figure out if the time taken was indeed sufficient or not as you're probably going to start noticing things about that position that you didn't before. If you play online, turn on move-timestamps to track the time used for you.

When you get a game reviewed/critiqued by a stronger player, it is always worth asking "How much time would you take (for a slow game) in a position like this?". You'll find very interesting answers and notice telling deltas between your sense of time management  and theirs! (they would really use their time in critical positions way more than you did but but spend very little on things that you probably worried a lot about).

One more problem that is kryptonite for my own time management is my current state of mind : lethargy, hungry, tired, over-caffeinated, distracted with other windows on my screen etc. ... I've signed up for G/120 games when I really only had it in me for a G/5 and vice-versa ... a lot of people tend to be confused about playing a time-control that's readily available (Hey, I can start a game right away!) vs. playing a time-control that's right for them but they need more patience (wait longer online) or have to put in some work (travel to a local club) in order to play it!!!  A unbalanced diet of too much blitz (or too little of it) can often impair your brain's ability to gear-shift suddenly to games with different time controls.


Is there a forced mate/ winning advantage? Recently I played a game in a High School league match as the top board. I played f4 followed by d5 (very standard). I played passively and waited out his attack and soon gained the momentum. At around the 25th move we progressed to this situation:

 [FEN "r5k1/p1q5/5rp1/2p1Np2/1p1n1P2/1P1PR3/P1P2Q2/1K2R3 w - - 0 1"]
 [Title "White to Move"]

It was my move and I saw mate in 3 with Qh4/Rh1/Qh8++.

So I played Qh4 attacking his rook and impending mate. He responded Qg7 which I feel was a strong defense.

That's when I saw my winning move from this position:

 [FEN "r5k1/p5q1/5rp1/2p1Np2/1p1n1P1Q/1P1PR3/P1P5/1K2R3 w - - 2 2"]
 [Title "White to Move"]

Nd7!

How does he respond without going down the exchange or significant material?

If - QxN

QxR down the exchange and threatening to take more.

He plays Rd6?

[FEN "r5k1/p2N2q1/3r2p1/2p2p2/1p1n1P1Q/1P1PR3/P1P5/1K2R3 w - - 4 3"]
[Title "White to Move"]

Re8+ now wins, right? There's a mate there for sure, but can he escape without losing his queen? If not the game?

     [FEN "r3R1k1/p2N2q1/3r2p1/2p2p2/1p1n1P1Q/1P1P4/P1P5/1K2R3 b - - 5 3"]
     [StartFlipped "0"]
     [Title "Black to Move"]

black resigns.

EDIT:
After some analyizing I think after Nd7 Black has lost. I cant see any possible escape from an actual Mate. please correct me if I am wrong.

Congratulations on a fine win. I see you have dominated the center with your knight which is backed up by doubled rooks on an open file.  Your king is in a safe position, compared to black's drafty King position. Black's queen is passive though not poorly placed. One of black's rooks is still in the box and is undefended.  It's vulnerable.  The other rook is also undefended and passive. But at least it is offering a feeble defense.

If you dilly-dallied, Black could move his knight to the awesome c3 square. So I am glad you did not do that. Also, if the pieces suddenly disappeared from the board, he would have a passed pawn on the f-file which could be fatal for you.

This position proves the adage, "If you find a good move, wait, and find a better move."  White wins with Qh4.  I'm sure you can win this game by force but I can't find a mate. It's amazing how resilient even crummy positions can be, if the losing player is willing to play until the bitter end.

This statement set off my danger alarm:

  QxR down the exchange and threatening to take more.

Being up the exchange is not a clear-cut win. You need to see the 'more' before assuming you're going to get the full point.

Qh4 is spot-on in that it forwards an agenda (exploit the drafty house) while hitting the lose rook. What's not to like?  But what I think you have missed here is the wretched state of the g6 pawn.  What if you double up on it with Qg2.  Now you're threatening to denude the king even more, while hitting the lose liability, oops I mean rook, on a8. Because Black's rooks are lose, you can move with tempo. It's like getting free moves.

[FEN "r5k1/p1q5/5rp1/2p1Np2/1p1n1P2/1P1PR3/P1P2Q2/1K2R3 w - - 0 1"]

1. Qg2 Raf8 2. Nxg6 (2... a6?? 3.Ne7+ Kf7 4.Qd5+ looks_strong) Rxg6 3. Qxg6+ Qg7 4.Qd6

The a6 move is a throw-away to show what can happen if Black plays poorly. It's what's coming if he does not take evasive action.

The main line sees you getting an exchange and a pawn. Super easy, too, and offers Black nothing in return.  Now your queen dominates black's undefended queenside. The c5 pawn will likely fall, leaving the Knight trapped. If he saves the Knight, you probably get the b4 pawn if you want it.  NOW if the pieces drop off, you have connected passed pawns.

Black's king will never be safe with white's queen and rooks on the board. This means he must always defend against fast checkmates and getting pieces pinned against the king. He's going to be down material and defensive. Further, I don't see how black holds the c5 pawn and he's in danger of losing the knight which is hemmed in.

Edit - I like to run positions in Stockfish (a chess engine.)  I let this one run. 20 minutes into its analysis, it switched black's first response from Raf8 to Nb5.  That is, it advocates that black simply drop the rook on a8. 1. Qg2 Nb5 2. Qxa8. wow. It rates the initial position as a crushing win for white. What is important to realize is that the moves are there if you're clever enough to find them.


What should I do when I have no ideas and no strategies? I'm really a beginner in chess, and I just know the rules. So many times in the game I have no idea what should I do. None of my pieces are in danger and I don't have any strategies.

What should I do at this point? Make a worthless move, like moving a pawn? Try to make some space for my knights and bishops?

This is very hard to answer since the question is very broad, but in the opening, always ask yourself "what piece haven't I moved out yet?" If you move pieces twice or three times in the opening, and I am developing each one after only one move, soon you will be fighting with only two or three pieces against me with 5 or 6. You will not win that way.

Other than that, ask yourself what pieces of yours are not defended, and make sure they are safe; and conversely, look at what your opponent has that is undefended, and see if you can take advantage of that. Not losing pieces is the biggest problem for weak players.


Chess Tempo #97369 - Theoretical win or draw? The following tactics problem is problem #97369 from ChessTempo. It is a position from a game between Yuri Yakovich and Pavel Kotsur. It's black's move.

The idea of the tactics problem is to find black's best move from the shown position.

But my question is slightly different: If both players play perfectly from the position shown in the diagram, can black force a win, or can white force a draw?

[FEN "6k1/5p2/1Pp3pb/2q4p/1rNpPP2/3Q2PP/8/5RK1 b - - 0 1"]

I tried using a couple of chess engines to analyze the position. The lines they suggested gave black a positive score, but didn't seem to give a forced win.

So what do you think: is it a theoretical win for black or can white escape with a draw?

I think it's a forced win for black.

Black can start with 1...Qxc4 after which the next five white moves are forced to avoid a fast loss.

[FEN "6k1/5p2/1Pp3pb/2q4p/1rNpPP2/3Q2PP/8/5RK1 b - - 0 1"]

1...Qxc4 2.Qxc4 Rxc4 3.Rb1! Bf8! 4.b7! (4.e5!? d3 5.b7 d2 6.b8=Q Rc1+ 7.Kf2 d1=Q) Bd6! 5.b8=Q+ Bxb8 6. Rxb8+ Kg7

Black is a pawn up and has connected passed pawns and should try to exchange pawns to simplify to a won end-game. The game might continue for example as follows:

[FEN "1R4k1/5p2/2p3p1/7p/2rpPP2/6PP/8/6K1 b - - 0 6"]

6... Kg7 7.e5 c5 8.Rd8 Rc3 9.Kf2 h4! 10.gxh4 Rxh3 11.Rc8 Rc3

The computer still doesn't find a line that leads to an obvious win but it looks like a hopeless situation for white and the computer playing against itself gives a win for black. Here's an example way to continue the game:

[FEN "2R5/5pk1/6p1/2p1P3/3p1P1P/7r/5K2/8 b - - 0 11"]

1... Rc3 2. Rc7 Kf8 3. Ke2 c4 4. Kd2 Rf3 5. Rxc4 Rxf4 6. Rc8+ Kg7 7. Rc7 Re4 8. Re7 Rxh4 9. e6 Kf6 10. Rxf7+ Kxe6 0-1

The final position is a table base win for Black.

If you think there any errors in this analysis (in particular, weak moves for white that changed the value of the position from drawn to lost) then please let me know.


Kasparov quote reference Kasparov apparently said:

  By strictly observing Botvinnik's rule regarding the thorough analysis
  of one's own games, with the years I have come to realize that this
  provides the foundation for the continuous development of chess
  mastery.

Does anyone know what this rule is precisely that Kasparov refers to and/or in what source Botvinnik stated the rule?

I think in Yermolinski's "The Road to Chess Improvement" he says that he decided to follow "the most common advice one can find in the works of Alekhine and Botvinnik , which can be put into simple words - study your games". Of course Yermolinski takes it much further saying that "study your games" means to do a thorough analysis of each of your games even going as far as to write full annotations for them.

The closest I find in Botvinnik quotes is:

  I claim that nothing else is so effective in encouraging the growth of
  chess strength as such independent analysis, both of the games of the
  great players and your own

This can be found in several quote sites - http://chess-quotes.blogspot.co.uk/2014/07/botvinnik.html is one such example.


Three way fork-Why take the rook instead of the queen? I just finished off a game and decided to do some analysis because I had a position that I was thinking about for a little bit.
I ran the game through Stockfish and the move I was thinking about was one Stockfish disagreed with.
[FEN "r1b1k1r1/pppq1pB1/2nb1N1p/8/8/5N2/PPP1BPPP/R2QK2R b KQq - 2 12"]

1. Nxd7+ Ke7

I played Nxd7, however, Sockfish suggested that I should play Nxg8+.
The only thing I can think of is looking at relative value.  The suggested move would result in a rook (5) and Pawn (1) for no material lost, while Nxd7 move would result in a queen (9) and pawn (1) for a knight (3).  Doing the math, the Nxd7 move still results in a better move. That or it doesn't like me opening up Black's white bishop
I let the engines play it out from this position and in both instances the Nxd7 results in a mate faster than the Nxg8+ move.
Because I can't see any reason the the Nxh8+ move is better than the Nxd7 move, is anyone able to assist or is Stockfish drunk?

Both moves lead to crushingly won positions for White, so all things considered it doesn't matter which one you choose. For me, Stockfish shows +14 for Nxg8+ and +9 for Nxd7. The difference between +9 and +14 is a lot less significant than the difference between, say, +0.5 and +2.5.
About the material calculation you gave: Nxd7 costs two minor pieces for the queen rather than just one, since if Black responds to Nxd7 with ...Rxg7 then the knight on d7 is also lost. So to the extent that this matters, on balance it probably favours Nxg8+ (which gains a whole rook).


Alphazero-Stockfish game 10 move 19 Given sufficient analysis time, say 24h per move on an decent computer, can current top chess engines (including Stockfish) eventually "see" that move 19 by Alphazero is actually good, and even suggest that move? And in general elevate the play so as to discover many Alphazero key moves in the others games as well (which could have neutralized Alphazero)?
Games here: https://arxiv.org/pdf/1712.01815.pdf

Current top engines running for 24hours would change their evaluation and find some improvements but would not be able to find ALL the key moves that A0 did.

"Old style" engines problems are twofold:

their eval functions are worse than A0(because of humans adjusting heuristics). This is somewhat similar to why "blank-state" A0 beats AlphaGo which was "seeded" with human games.
Their search algorithms suffer from horizon effect(https://en.wikipedia.org/wiki/Horizon_effect) that A0 was able to exploit in the examples given.

Let's take Game 10 in question:

[fen ""]
[White "AlphaZero"]
[Black "Stockfish"]
[Date "2017.12.05"]
[Result "1-0"]

1. Nf3 Nf6 2. d4 e6 3. c4 b6 4. g3 Bb7 5. Bg2 Be7 6. O-O O-O 7. d5 exd5 8. Nh4 c6 9. cxd5 Nxd5 10. Nf5 Nc7 11. e4 d5 12. exd5 Nxd5 13. Nc3 Nxc3 14. Qg4 g6 15. Nh6+ Kg7 16. bxc3 Bc8 17. Qf4 Qd6 18. Qa4 g5 19. Re1 Kxh6 20. h4 f6 21. Be3 Bf5 22. Rad1 Qa3 23. Qc4 b5 24. hxg5+ fxg5 25. Qh4+ Kg6 26. Qh1 Kg7 27. Be4 Bg6 28. Bxg6 hxg6 29. Qh3 Bf6 30. Kg2 Qxa2 31. Rh1 Qg8 32. c4 Re8 33. Bd4 Bxd4 34. Rxd4 Rd8 35. Rxd8 Qxd8 36. Qe6 Nd7 37. Rd1 Nc5 38. Rxd8 Nxe6 39. Rxa8 Kf6 40. cxb5 cxb5 41. Kf3 Nd4+ 42. Ke4 Nc6 43. Rc8 Ne7 44. Rb8 Nf5 45. g4 Nh6 46. f3 Nf7 47. Ra8 Nd6+ 48. Kd5 Nc4 49. Rxa7 Ne3+ 50. Ke4 Nc4 51. Ra6+ Kg7 52. Rc6 Kf7 53. Rc5 Ke6 54. Rxg5 Kf6 55. Rc5 g5 56. Kd4 1-0

This is a game worthy of Tal from Alpha0! White is making a positionally based long term sacrifice of a piece and pawn. Ie nice idea but surely a computer would defend this. However human intuition turns out wrong here.

At move 19. we are at least 30 ply (15 full moves) from Stockfish giving back the piece.

There is no way for regular engines to fully search 30ply deep in the middle game without improvements in their pruning algorithms.

As an experiment I run 30 threads(15 cores) on latest Stockfish 8 at 25kn/s for some time with various hash sizes. So my machine was 1/3 of Google's -> ie I have to run it at least 3 times longer.

Even at move 32. Stockfish was thinking it was better.

What was interesting that within 1 second of me making the move Stockfish was suggesting as good the eval dropped and Stockfish realized the move was bad. This could be the limits on its hash size or just the horizon effect.

A0 will hopefully provide inspiration for regular engines to incorporate new techniques.

My hope is something like Stockfish Zero which would use 1000s of crowdsourced GPUs to train the network then only requiring  a single high end GPU to play.


Are all grandmasters capable of playing blindfold? There seems to be no shortage of stories about top rated players playing blindfold, either recreationally, or in tournaments. I'm curious whether all top players have this ability. Are there are GM-level players (current or former), for instance, known to not have any ability to play blindfold?

As of this post all super grandmasters can play blindfold. For young GMs who are just starting out playing blindfold, they may not be super good at first but they should be able to pick it up quickly. Also, for old GM's it might be harder for them to play blindfold, as short term memory and spatial reasoning might be diminished. But most, if not all, GMs should be able to play blindfold chess.


Elo rating software with automatic random matchups This question is not about chess per se, but I am looking for a software that could generate random matchups through a list of 200ish options/people, then I could choose the winner and it would rank the outcomes with Elo rating (or something similar that would also work).

I'm currently using EloRater, but I have to manually generate random numbers from an external source to then create the matchups, scroll down through the list, find them, choose the winner, etc.  I am doing simulations and I need to do many, many matchups from a list. Thus, something that is user-friendly and speeds up the process would greatly help.

I think such software probably exists for chess. Does anyone of anything that could help me?

Dont know elorater but there is likely a way through the opsys to randomly pick (that part is easy) players to match and then insert them automatically into elorater instead of typing them in.  If they have a way to import tournament results you might be able to automate it even easier.  Just create all the random matchups you want and then submit it for rating.


How to maintain the initiative? What are some ways one can keep the initiative?  I find in many cases I have the upper hand if I am able to keep my opponent defending instead of creating his own attack.  Are there openings or certain moves in the beginning that help keep the initiative?

From my own experience the best way to maintain initiative is remain active. Don't make timid moves, you will occasionally overreach doing this but you will learn what is overly bold and what is simply active play. Also I have found that the better a plan I have the more active my play, it is when I am floundering around not sure where to go from here that I have the worst time keeping initiative.

Be familiar with the general opening principals, (open lines, knights before bishops, rooks on open ranks, don't make more than 2 pawn moves in the opening, don't move that same piece twice in the opening, etc) none of these are hard fast rules that should never be broken but they will keep you in the right direction in the first part of the game.

Finally I would be familiar with the basic weapons of chess, (pins, forks, etc) and learn to look for them not only in the current position but in positions that you could reach if you make whatever move you are contemplating. They will tell you both what to watch out for and what tactical opportunities you have to advance your own game, and extend, or update, your plan as the game proceeds.

One final thought, have a reason, tactical or not but a specific reason, for every move. If you move without a specific reason your are floundering and no longer on the initiative.


Undrawable Openings? What are some openings that are extremely difficult to obtain a draw in? I have been recently playing openings like the Ruy Lopez and facing a lot of draws.

If you play more aggressively and choose sharper lines, your draw rate will go down - though not necessarily the way you want it to.

Generally gambit lines are sharp, whether you are giving or taking the pawn. So you could play the King's Gambit instead of the Ruy Lopez.

Another possibility is to play the Italian Game and choose the Evans Gambit against 3…Bc5 and 4.Ng5 against 3.Nf6.

But although the Ruy Lopez is a rather strategic opening, a high draw rate in your games is more likely connected to your style of play. If you keep the tension, i.e. not going for exchanges, and try to build a strong kingside attack, you should get a lot of decisive games even in the Ruy.


convert stockfish pv output to show piece names What are suggested coding snippets to add pieces to pure algebraic notation (this would change g1f3 to Nf3) when using the chess.js and chessboard.js (javascript) interface.  Stockfish uses this type of raw notation and I would like to change it.

Answers such as the ones from the link below are not helpful. for example: the computer knows the names of the pieces.

Changing UCI output to include piece names

Sorry I don’t know any JavaScript but here is the basic code (in pseudo code) for the problem:

SELECT CASE Board(Move(1),Move(2))
CASE “N”
      Move <== “N” + Move(3) + Move(4)
CASE “P”
      Move <== Move(3) + Move(4)
CASE “K”
      Move <==“K” +  Move(3) + Move(4)
CASE “R”
      Move <==“R” +  Move(3) + Move(4)
CASE “Q”
      Move <==“Q” +  Move(3) + Move(4)
CASE “B”
      Move <==“B” +  Move(3) + Move(4)
END SELECT

This is assuming there is a 2D array holding the board named “Board” and a string “Move” holding the move about to be played.

Hope this has helped.


Alpha-beta add variance/handicap I want to implement a handicap for my engine and I'm struggling with it. I using alpha-beta pruning.

In my current approach I set a variance variable in centipawns and let the engine choose a move in the variance range. An example with white to move and variance = 5;

25 d2d4 d5d7 ...
23 e2e4 e5e7 ...
20 b1c3 e5e7 ...
18 g1f3 d5d7 ...
...

In this case the engine can choose between the first three moves cause they are all in range of 20-25. A random move of those three is picked, all other moves are ignored.

I implemented this and let it run against my "best move engine". To my surprise in 200 games the "best move engine" wins like 95% of the time. Which is in my opinion way to high.

As I dove deeper I realized that the "variance engine" picks sometimes totally blunder moves. Like sacking a queen without any compensation. I triple checked the code for picking the "random" move in the variance range. Its perfectly fine. So I think my alpha-beta is the problem here. Some questions:

Should alpha-beta in general be capable of implementing something like variance picking. If so, what could I have done wrong or what am I missing?
Is there another way of implementing a handicap for an engine. Couldn't really find anything on the internet.

Even one minor error could cost the game against a perfect opponent, so 95% losing rate is generous.  However, I don't understand how the "best move" engine could lose any games in the second trail.

The ABSearch could be modified, but it's easier to perform this at the RootSearch function.  Since the arrays for the current moves and their respective scores are present here, it's easy to implement, and the RootSearch should be able to self-correct on future moves better than anything done in the current ABSearch.  (This is really messy.  Sorry.)
I've seen three ways to limit strength.

a.  Make a weak move at a specific interval.  When playing against its sponsors, a computer was told to make a random king move every 10 moves.

b.  The computer wasn't allowed to make a move in which the eval was above a threshold.  So, for a drawing computer, the computer wouldn't make a move where the eval was above a pawn or had to make a mistake to lower the eval to below this range.  This i similar to your variance, but instead of within the top range, it's a final eval of +- a pawn.

c.  The chess engine Galahad (I can't find its source anymore.) allowed you to change some eval constants.  Lowering the penalty for a weakness, such as doubled pawns, does lower its strength, but not in a dramatic manner.

Trappy Beowulf trys to implement a more human engine where it does try for traps instead of the best move.  I haven't read the code, so I can't explain how it accomplishes this, but I assumed that it goes for simple, one move threats, and when this threat is parried, the positions is slightly worse.

I"d like to give a special thanks to the four examples and the OP for thinking out of the box.  Not just trying to be the best, but for being usable.

EDIT:  A better example is "c" would be a piece-square value.  By adjusting this variable, you could make the computer think that g3 is a better square for the knight than e5.  This could be used to make the computer decentralize pieces or make them more defensive.  Changing the pawn protection around the king values, you could make the computer make these weakening moves and test your attacking skills.  The options are only limited by your imagination.


Can you solve this chess problem of a lone knight against numerous opposing pieces? [FEN "8/1nq5/bppp4/1p1k1K1N/1rrp3b/2pp2p1/8/n7 w - - 0 1"]

I found this interesting and unique chess problem online.
Disclaimer: This is not necessarily a position from a game. It's just a beautiful composition wherein your objective as White is to checkmate the black king. White is moving from bottom to top and Black is moving from top to bottom.
This problem was composed by Hungarian Engineer Ottó Bláthy.
It's white turn and it's mate in 12 moves. Can you find the winning move continuation for white?

OK

The check must come from the knight (D'uh!)
The black king must be on c5 for the mate
The white king must be used to cover any empty squares to the right of the black king - thus the white king must move, thus there must be at least one non-checking move
On a non-checking move Black can try to release the prison by Ra4
The only way white can cover this is for the winning check to come from d3, as this covers b4 and the knight can not be captured there (unlike a6 after the rook moves)
When white makes the non-checking move he must be in a position to deal with threats from black, in particular the black queen, and checks from the black knight on c7 and the black bishop on h4
If on the non-checking move white plays Ke6 directly the knight check from d8 will break the prison
Thus the king must go to e4, attracting the black pawn to d5 with check, after which, if the black queen has been eliminated, the white king can go Ke6 Nd8+ Kd7 and it can't at that point be driven away

Putting this all together leads us to
[Event ""]
[Site ""]
[Date "????.??.??"]
[Round ""]
[White ""]
[Black ""]
[Result "1-0"]
[FEN "8/1nq5/bppp4/1p1k1K1N/1rrp3b/2pp2p1/8/n7 w - - 0 1"]

1.Nf4+ Kc5 2.Ne6+ Kd5 3.Nxc7+ Kc5 4.Nxa6+ Kd5 5.Nc7+ Kc5 6.Ne6+ Kd5 7.Nf4+
Kc5 8.Ke4 d5+ 9.Ke5 Bf6+ 10.Ke6 Nd8+ 11.Kd7 Ra4 12.Nxd3# 1-0

I think that's it, though I can't see at the moment what the Black Knight on a1 is doing


Let's beat the Benko Gambit! I play 1. d4 as White and I have success against almost all Black defences, except the Benko Gambit, where I score about 30%.

My style is that I like solid, closed, positional games if I can, but I can handle myself tactically too. However I find that I lag behind in development, and to make matters worse, even if I reach an endgame, the Benko structure is quite solid, so even here Black has good chances.

Can you suggest a variation for White that leads to a solid, positional game against the Benko Gambit?

My elo is 2050.

I play Benko as black and am a FM. The most trouble I have in quick games is with declined cxb5 a6 b6 line. Without the a line open I just do not have the play that Benko player craves.

Also, I noticed that stronger(IM+) players tend to go for the b6 line, while weaker players either take the pawn on a6 or decline the gambit with something else. For example allowing black to push to b4 has been good for me as black.


Chess Strategy Defined I am trying to define chess strategy for myself, and I came up with the following explanation which I would like to get feedback on.

  Chess strategy can be defined as the creation of long term plans that
  will dictate your next several moves. In order to achieve these plans,
  you can argue that the chess player will resort to either positional,
  tactical or endgame devices.

My questions are:

Do you agree on the above?
How would you define chess strategy?
If you had to choose only 1 game that illustrates chess strategy in
action what would that game be?
What methods do you use to evaluate a position to determine your
strategy?

Update 4/17/16: Blog post about Chess Strategy.

1. Do you agree on the above? 2. How would you define chess strategy?
From Chess Strategy: Move by Move by Adam Hunt, he defines chess strategy in his introduction as:

Chess strategy is concerned with the correct evaluation of a position and the formulation
of an effective plan based upon its characteristic features. When the word ‘strategy’ is
mentioned, people tend to jump to the conclusion that we are talking about long-term
middlegame planning, and that you have to be some sort of psychic who can see the future,
but that is rarely the case. Many features of a given position which are strategically
important will evolve out of the opening and finish in the endgame, so it would be foolish
to completely ignore these phases of the game. Plans can be short or long term, depending
on how the landscape in front of you is changing as the game progresses. This is why the
subject is so complex and so much material is available on it.

Emphasis is mine.
So, to contrast to your definition:

Hunt does not restrict himself to long term planning in his definition
It spans all phases of the game, including the opening
There is no explicit mention of tactical/positional devices, but I think it is covered in his "characteristic features"

3. If you had to choose only 1 game that illustrates chess strategy in action what would that game be?
On the basis of the complexity of the subject, no one game will highlight all elements of chess strategy.
4. What methods do you use to evaluate a position to determine your strategy?
This is covered in How To Reassess Your Chess by Jeremy Silman. He calls Hunt's "characteristic features" imbalances, i.e. differences in the Black and White armies. He considers:

Superior Minor Piece: Bishops vs. Knights
Pawn Structure—Weak Pawns, Passed Pawns, etc.
Space
Material
Control of a Key File (or indeed control of a key line)
Control of a Hole/Weak Square
Lead in Development
Initiative
King Safety


What projects have been undertaken to solve chess completely? Chess is not completely solved yet but what efforts have been undertaken to solve it? Has there been a large project like the HGP or is something like that even worth pursuing? What failed efforts have been there if any? I am speculating that the the Alpha Zero project must have taken some steps towards that end.
EDIT:-Answers ponder on the point that is extremely difficult to solve chess which i have clearly indicated in the first line in the question. What I would like to know that are there or have there been any projects that try to solve chess. Like that Moscow university 7-piece tablebases and any efforts like that. It is clearly an expensive problem to solve but who is doing it and what approaches are being taken? It is often said that there are more chess combinations than atoms in the universe (probably because of that ad) but so are the real numbers but we have a rich theory about that. We also know a great deal about the universe as well but we had to try hard to get to that point. Is chess being treated the same is my question.

Endgame tablebases can be seen as such an effort, in that we started at few pieces and have increased the number. In 2012, 7 piece tablebases -from Moscow state university were generated, so chess is solved for positions of 7 or fewer pieces (including the kings).
The problem is, the 7 piece tablebases take about 140 TB in storage. 8 piece tablebases would take about 10 petabyte of storage, and a computer with 50 TB of ram (source) to keep hashes in memory to generate them in reasonable time (a few years?). I guess it would be doable these days if someone makes the millions of dollars available. 9 seems way out of reach.
So it will take a while before we get to 32.


Why was the engine giving such positive evaluations for my game with equal material? I just played a game on chess.com that was roughly equal material until the final move (I was one pawn up for most of the game) but the engine favours my position to the extent that by move 12 I had a +5.5 evaluation which steadily rose until the end of the game.
I can see that at move 32, all of black's pieces are stuck in a corner while mine are active around the king and because of that, there is a forced mate that black doesn't have time to stop, but for example, on move 22 Stockfish 12 gives me +7 at depth 22 being only one pawn up even though black's pieces are out.
What is it about this game that made the engine so happy? And more importantly, how can I consistently/intentionally play like this? A lot of the moves I made were deemed inaccuracies because I guess I just didn't understand whatever amazing plan Stockfish saw.
[FEN ""]
[Event "Live Chess"]
[Site "Chess.com"]
[Date "2021.01.23"]
[Round "-"]
[White "Me"]
[Black "NN"]
[Result "1-0"]
[CurrentPosition "r1b1k3/1n1q1p2/1pB1p3/4P3/1P5B/p1P1PQ2/P4P2/1K5R b q -"]
[Timezone "UTC"]
[ECO "D00"]
[ECOUrl "https://www.chess.com/openings/Queens-Pawn-Opening-Accelerated-London-System"]
[UTCDate "2021.01.23"]
[UTCTime "10:53:13"]
[WhiteElo "1375"]
[BlackElo "1343"]
[TimeControl "600"]
[Termination "matt2230 won by resignation"]
[StartTime "10:53:13"]
[EndDate "2021.01.23"]
[EndTime "11:03:23"]
[Link "https://www.chess.com/live/game/6320705182"]

1. d4 d5 2. Bf4 Nf6 3. e3 h6 4. Bd3 g5 5. Bg3 h5 6. h3 h4 7. Bh2 Nc6 8. c3 e6 9.
Nf3 Bh6 10. Nbd2 g4 11. hxg4 Nxg4 12. Qe2 b6 13. Bg1 Bg7 14. Nh2 Nf6 15. Nhf3 h3
16. gxh3 Ng4 17. O-O-O Nf6 18. h4 a5 19. Kb1 a4 20. Bh2 a3 21. b3 Na5 22. Ne5
Rxh4 23. Bg3 Rxh1 24. Rxh1 c6 25. b4 Nb7 26. Nxc6 Qd7 27. Ne5 Qa4 28. Bc2 Qa7
29. Bh4 Ne4 30. Nxe4 dxe4 31. Bxe4 Bxe5 32. dxe5 Qa4 33. Qf3 Qd7 34. Bc6 1-0

on move 22 Stockfish 12 gives me +7 at depth 22 being only one pawn up
even though black's pieces are out

Black's pieces are not all out and the ones that are aren't on the right squares. Black is still several moves away from being able to castle safely. Meanwhile you have completed development, including the queenside castling safety move Kb2, and some of your pieces are on very good squares.

how can I consistently/intentionally play like this?

The best move you made was picking a patzer for an opponent, someone who develops two pieces and then starts a wild attack making pointless wing pawn moves. The next best thing you did was obey standard opening principles of developing your pieces properly. Continue doing those two things, particularly the first, and you should win all your future games.


Has the 75 move draw rule ever been invoked in a FIDE rated standard game involving a GM? In the latest FIDE Laws of Chess the arbiter is supposed to step in and declare the game drawn if 75 moves are played by both sides with no captures and no pawn moves.

It would be understandable if this happened in blitz or rapid where the players are not recording the moves. It would also be understandable in games played by weaker player who may not know the rules.

Has it ever happened in a game of standard chess with a 30 second increment where the players have to record the moves and where at least one of the players is a GM?


Which chess website with the most correct online rating? I recently switched from chess.com to
lichess.org. This was because I enjoy live chess more and it seems like can find more live chess on Lichess while it chess.com keeps you waiting. Chess.com searches for who they think is your perfect opponent whereas Lichess lets you play whoever you want.
However, I’ve noticed that Lichess gives more points to the winner and takes away more points from the losers, and I mean much more. I don't know if I'm correct though, but I think I am. Lichess also gives youn a higher starting rating.
If I'm right, then which online chess website gives the most realistic chess rating to its users?

How do you define realistic for chess ratings? Actually, they are all realistic. Ratings should be considered inside their own population because your rating in server X is your performance relative to other players in the same server. As it depends the population you shouldn't compare one rating to another rating in another server. But if you really want to compare your rating to another population approximately, please see this method: How does Chesscube.com rating compare to USCF and FIDE ratings?

All chess rating systems follow almost same rules, but they have different converging speeds. This is what you explained in your question, one server gives less on win and takes less on loss, another one gives/takes more etc.

There is a thing, K-factor, in USCF rating system for example, to tweak this converging speed from game to game. Please see this topic: What does "half-K" mean in the USCF tournament rating system?

When you enter a rating population as a new player, you start with average rating of that population(generally). But it doesn't matter which rating you start with, even if you start from 3000, you will converge to your real rating as you play games. So, it's not about being realistic again.

And generally for all rating systems, your first 8 to 20 games will have super high converging speeds, to approximate your rating faster. After that, converging speeds drops to normal and ratings get stabilized.

So, shortly, your ratings will be different in different populations, and it's totally normal.


Has any other grandmaster gone as long undefeated like Capablanca? Between 1916 and 1924, future World Champion J.R. Capablanca, as of 1921, experienced a period of eight years without a single tournament defeat. He was then regarded as one of the world's best defensive players, although he also drew more than other grandmasters of similar stature. Has any grandmaster or world champion since then had an equal or longer record of being undefeated?

From this Chess.com Discussion

  In terms of games played, it would be Tal with 95 games (46 wins, 49 draws) from October 23, 1973 to October 16, 1974. He also has the second longest streak of 84 games (47 wins, 39 draws) from July 1972 to April 1973.
  In terms of time, Capablanca was undefeated for 63 games (40 wins, 23 draws from February 10, 1916 to March 21, 1924.


Why did Black play Ra8 in this situation? I am reading Kasparov Teaches Chess, and I had a problem about this situation below:

[FEN "R2K1B1R/PPP5/5P1P/3PP3/3N1pB1/3p1np1/pppb1qbQ/r2k1r2 b - - 0 1"]

Black plays Ra8? next, why? I think it's better not to leave the queen unprotected.

Sorry I may not have made myself clear. Kasparov gives this variation to demonstrate a certain response is a bad move. I know Ra8 is bad. But if there aren't good choices, you can't say this variation is actually bad, isn't it?

This is the original board situation:

[FEN "rn1qk2r/pb2bppp/1p2p3/1Bp5/3PP3/P1P2N2/2Q2PPP/R1B1K2R b KQkq - 0 1"]

1... Nc6 2.Ne5 Rc8 3.Qa4 Qc7 4.Qxa7 Ra8? 5.Bxc6+{White Wins}

And by giving such a variation Kasparov made a conclusion that Nc6 is a bad move. What if Black don't play Ra8? He can still possibly make equal trades, and thus Nc6 isn't really bad?

The point is, why is Nc6 a bad move?

Why Black play Ra8 in this situation?

He wanted to trap the White queen.

  I think it's better not to leave the queen unprotected.

You are correct, Black made a blunder, and now loses the game:

[StartFlipped "0"]
[fen "2r1k2r/Qbq1bppp/1pn1p3/1Bp1N3/3PP3/P1P5/5PPP/R1B1K2R b - - 0 1"]

1...Ra8 2.Bxc6++- Qxc6 ( 2...Bxc6 3.Qxc7+-) 3.Nxc6! Rxa7 ( 3...Bxc6 4.Qxb6+- ) 4.Nxa7+-

Your question is not entirely clear but I hope this post answers it. If you need help or you have further questions leave a comment.

EDITED IN RESPONSE TO THE OP EDIT:

  The point is why is Nc6 a bad move?

Nc6 is a bad move because it allows a decisive pin along the a4-e8 diagonal. The fact is that Bb7 is badly posted to defend the knight on c6. If he were at d7 then Nc6 would not be pined and Black would be fine.

After Nc6 White is able to exploit the bad positioning of the Bb7 to net himself a pawn on a7, and still keep the pressure on Nc6. After White captures on a7 we have the second pin on Qc7 which paralyses Black. Now he must castle, but then White can win a piece:

[StartFlipped "0"]
[fen "2r1k2r/Qbq1bppp/1pn1p3/1Bp1N3/3PP3/P1P5/5PPP/R1B1K2R b - - 0 1"]

1...O-O 2.Bxc6 Bxc6 3.Nxc6! Qxc6 4.Qxe7 $18 Qxe4+ ( 4...cxd4 5.O-O ) 5.Be3 Qxg2 ( 5...cxd4 6.cxd4 Qxg2 ( 6...Qd3 7.Rd1 $18 ) 7.Kd2 $18 ) 6.O-O-O $18

I have checked the lines with the engine. If you have any doubts you can run these positions through the engine yourself. The point is that center is fixed, and White can defend himself by exchanging rooks on the c-file. Furthermore, bishop defends well too, and queen can come fast to defense. Black may be able to make a pressure but it will not be a permanent one. White will untangle eventually and convert his extra piece.

If you still have doubts you can post the position as a new question and we can see if other members can spot something that I did not.

END OF EDIT

Hopefully this helped.

Best regards.


Helpmate in four and a half moves Merry Christmas everyone! Try this problem out that I made yesterday for SuperProblem.ru. With White to move, solve this helpmate, meaning White and Black work together to checkmate Black, in 4.5 moves. Enjoy!
[Title "me, SuperProblem.ru 12/24/2020, Helpmate In 4.5"]
[FEN "4b3/6p1/2p2pk1/8/K4r2/P7/2Pq1PPP/8 w - - 0 1"]


Does any PGN actually use the '%' (escape) or ';' (rest of line comment) mechanisms? Trawling through the PGN standard, I was surprised by two of the specifications:

An escape mechanism triggered by % at the start of a new line:

  There is a special escape mechanism for PGN data. This mechanism is triggered by a percent sign character ("%") appearing in the first column of a line; the data on the rest of the line is ignored by publicly available PGN scanning software. This escape convention is intended for the private use of software developers and researchers to embed non-PGN commands and data in PGN streams.

  A percent sign appearing in any other place other than the first position in a line does not trigger the escape mechanism.

A "rest of line" comment initiated by a semicolon ;:

  Comment text may appear in PGN data. There are two kinds of comments. The first kind is the "rest of line" comment; this comment type starts with a semicolon character and continues to the end of the line. [...]

They surprised me because I have never encountered them in any PGNs I've found "in the wild", so to speak. Has anyone encountered PGNs where these (escape mechanism or semicolon comments) are used?

You can use the percent sign to comment out a line of text in your PGN file (similar to Latex). For example, if you'd like to include personal comments that categorize the games within the database, such as % Games to study later. All such lines starting with % will not be interpreted by a PGN parser, so you can safely leave self-notes or other comments (that you might want to later parse in a script) in a PGN database.

An example of such a PGN file:

% Interesting games from Wijk aan zee

1. e4 e5 2. Nf3 Nc6 3. Bb5 Nf6 4. d3 d6 5. c3 a6 6. Ba4 Be7 7. O-O O-O 8. Re1
Re8 9. Nbd2 Bf8 10. h3 b5 11. Bc2 Bb7 12. d4 g6 13. a3 Nb8 14. d5 c6 15. c4 Nbd7
16. a4 Qc7 17. b3 Rec8 18. Ra2 bxc4 19. bxc4 a5 20. Nf1 Ba6 21. Ne3 Nc5 22. Nd2
cxd5 23. cxd5 Rab8 24. Ba3 Qd8 25. Qf3 h5 26. Raa1 Bh6 27. Rab1 Rxb1 28. Rxb1
Kg7 29. Nef1 h4 30. Ne3 Bf4 31. Nef1 Qc7 32. g3 hxg3 33. fxg3 Bh6 34. h4 Qd7 35.
Kg2 Nxa4 36. Bxa4 Qxa4 37. Bxd6 Qd4 38. Qf2 Qxf2+ 39. Kxf2 Bxf1 0-1

% Caro-Kann games:

1. e4 c6 2. Nf3 d5 3. Nc3 Bg4 4. h3 Bxf3 5. Qxf3 Nf6 6. Be2 e6 7. O-O dxe4 8.
Nxe4 Nxe4 9. Qxe4 Nd7 10. d4 Nf6 11. Qd3 Qc7 12. Rd1 Be7 13. c4 O-O 14. Be3 Rfd8
15. Qb3 Rd7 16. Bf3 Rad8 17. a3 h6 18. g3 b6 19. Kg2 c5 20. Qc3 a5 21. Rac1 cxd4
22. Bxd4 Ne8 23. h4 Bf6 24. Bxf6 Nxf6 25. b4 axb4 26. axb4 Rxd1 27. Rxd1 Rxd1
28. Bxd1 Kf8 29. Bf3 Ke7 30. c5 bxc5 31. bxc5 Kf8 32. Qb4 Ne8 33. Qb6 Qe5 34.
Bc6 Ke7 35. Bxe8 Kxe8 36. c6 Qd6 37. Kg1 g5 38. h5 f5 39. Qb7 Qd1+ 40. Kg2 Qd5+
41. Kh2 Qd4 42. Kg1 Qd1+ 43. Kg2 Qd5+ 44. Kh2 Qd4 45. Kg1 1/2-1/2

You can experiment with this by loading the PGN file (like the above) on for example chesstempo in order to sanity check the parsing, and see that those lines are indeed correctly ignored.

As for annotations and the use of the semicolon see this answer by Andrew.

Briefly, the semicolon is another way of indicating move annotations but it's not efficient as it requires including redundant characters and line-skips per annotation, e.g.:

1. d4; closed system
1...d5 2. c4

instead of 1. d4 {closed system} d5 2. c4. And the semicolon notation is rarely supported by PGN parsers. So the use of curly brackets {} is always recommended, as it's well supported, simple and intuitive to use and less prone to mistakes in the notation.


List of famous, but incorrect, chess problems Surely it has happened, that a famous chess problem turned out to be incorrect because some move was overlooked. Maybe a chess engine found out that a classic problem was incorrect! Is there a collection of such problems? Please give an example as well, if you know any.

You can find a list of 8039 cooked, which is the official term that means incorrect, chess problems here on the site Yet Another Chess Problem Database, often shortened to YACPDB. Another option is a list of 28670 problems on the Die Schwalbe Chess Problem Database that can be found by inputting 'COOKED' into the search bar.
A famous example of an incorrect problem is this problem, which calls for White to play and checkmate Black in 8 moves.
[Title "William Shinkman, St. Louis Globe-Democrat 1885, Mate In 8"]
[FEN "k7/P7/P7/P7/P7/P7/P7/R3K3 w - - 0 1"]

The intended solution was 1. 0-0-0!, White castling queenside, followed by 1... Kxa7 2. Rd8 Kxa6 3. Rd7 Kxa5 4. Rd6 Kxa4 5. Rd5 Kxa3 6. Rd4 Kxa2 7. Rd3 Ka1 8. Ra3#.
But as it turned out,, 1. Kd2! also checkmates on the 8th move, thereby making the problem incorrect. An example of a possible continuation is as follows: 1. Kd2 Kxa7 2. Re1 Kxa6 3. Re7 Kxa5 4. Re6 Kxa4 5. Re5 Kxa3 6. Kc3 Kxa2 7. Re1 Ka3 8. Ra1#.
On Tim Krabbe's website, there is an article entitled "The Kuwait Immortal, that is linked in Journal Entry #140.
Within, Krabbe published a correction of Shinkman's problem by Bader Al-Hajiri. The White king is now on g1, utilizing Chess960 to allow for a cook free long-range castling as the key.
[Title "Bader Al-Hajiri After William Shinkman), Tim Krabbe's Website  9/19/2007, dedicated to Tim Krabbe, Mate In 8 Under Chess 960"]
[FEN "k7/P7/P7/P7/P7/P7/P7/R5K1 w - - 0 1"]


Is there a binary of Scid vs Mac which works on macOS Mojave? I had ScidvsMac 4.19 running on my Mac - ScidvsMac-4.19.dmg from https://sourceforge.net/projects/scidvspc/files/mac/ - but after upgrading to macOS Mojave (10.14.1) it doesn't run - the icon just bounces forever.

I have been trying to use macports compilers to compile the latest source but I am just lost in dependency hell right now because I can't seem to install libgcc7 or libgcc8 properly. I might try to blow everything away and start a fresh install ... but wondering if anyone has overcome these problems?

Your question is pretty old. Did you succeeded to resolve your problem? I am running scidvsmac 4.19 on Mojave without any problem. You may download it here:

http://scidvspc.sourceforge.net/#toc3

Best greetings

marek