670:
340:
666:. Other than it being one of the most complicated game playing programs written at the time, it is also well known for being one of the first adaptive programs. It learned by playing games against modified versions of itself, with the victorious versions surviving. Samuel's program was far from mastering the game, although one win against a blind checkers master gave the general public the impression that it was very good.
400:
52:
441:
21. 32-28 31-27 22. 16-19 27-24 23. 19-23 24-20 24. 23-26 29-25 25. 26-30 25-21 26. 30-26 14-9 27. 26-23 20-16 28. 23-18 16-12 29. 18-14 11-8 30. 28-24 8-4 31. 24-19 4-8 32. 19-16 9-6 33. 1x10 5-1 34. 10-15 1-6 35. 2x9 13x6 36. 16-11 8-4 37. 15-18 6-1 38. 18-22 1-6 39. 22-26 6-1 40. 26-30 1-6 41. 30-26 6-1 42. 26-22 1-6 43. 22-18 6-1 44. 14-9 1-5 45. 9-6 21-17 46. 18-22 BW
240:
211:. They are invariably split into one darker and one lighter colour. Traditionally and in tournaments, these colours are red and white, but black and red are common in the United States, as well as dark- and light-stained wooden pieces. The darker-coloured side is commonly referred to as "Black"; the lighter-coloured side, "White".
356:
and can make for more exciting matches. Three-move restriction has been played in the U.S. championship since 1934. A two-move restriction was used from 1900 until 1934 in the United States and in the
British Isles until the 1950s. Before 1900, championships were played without restriction, a style
440:
1. 9-14 23-18 2. 14x23 27x18 3. 5-9 26-23 4. 12-16 30-26 5. 16-19 24x15 6. 10x19 23x16 7. 11x20 22-17 8. 7-11 18-15 9. 11x18 28-24 10. 20x27 32x5 11. 8-11 26-23 12. 4-8 25-22 13. 11-15 17-13 14. 8-11 21-17 15. 11-16 23-18 16. 15-19 17-14 17. 19-24 14-10 18. 6x15 18x11 19. 24-28 22-17 20. 28-32 17-14
284:
A jump consists of moving a piece that is diagonally adjacent an opponent's piece, to an empty square immediately beyond it in the same direction (thus "jumping over" the opponent's piece front and back ). Men can jump diagonally forward only; kings can jump in any diagonal direction. A jumped piece
296:
are possible, if after one jump, another piece is immediately eligible to be jumped by the moved piece—even if that jump is in a different diagonal direction. If more than one multi-jump is available, the player can choose which piece to jump with, and which sequence of jumps to make. The sequence
744:
at the peak of the project and around fifty later on, the team made 10 calculations to search from the initial position to a database of positions with at most ten pieces. However, the solution is only for the initial position rather than for all 156 accepted random 3-move openings of tournament
326:
The
December 1977 issue of the English Draughts Association Journal published a letter from Alan Beckerson of London who had discovered a number of complete games of twenty moves in length. These were the shortest games ever discovered and gained Alan a place in the Guinness Book of Records. He
373:, i.e. removed from the board. After huffing the offending piece, the opponent then takes their turn as normal. Huffing does not appear in the official rules of the World Checkers Draughts Federation, of which the American Checker Federation and English Draughts Association are members.
351:
In tournament
English draughts, a variation called three-move restriction is preferred. The first three moves are drawn at random from a set of accepted openings. Two games are played with the chosen opening, each player having a turn at either side. This tends to reduce the number of
331:(author of the Colossus draughts program) published a paper on his website presenting an exhaustive analysis showing that there exist 247 games of twenty moves in length (and confirmed that this is the shortest possible game) leading (by transposition) to 32 distinct final positions.
700:
to interactively play a round of checkers with visitors. Originally, the program was deliberately simple so that the average visitor could potentially win, but over time was improved. The improvements proved to be frustrating for the visitors, so the original code was reimplemented.
226:. Some sets have pieces with a crown molded, engraved or painted on one side, allowing the player to simply turn the piece over or to place the crown-side up on the crowned man, further differentiating kings from men. Pieces are often manufactured with indentations to aid stacking.
726:
in a thirty-two game match. The final score was 1–0 with 31 draws for
Chinook over Don Lafferty. In 1996 Chinook won in the U.S. National Tournament by the widest margin ever, and was retired from play after that event. The man-machine title has not been contested since.
289:
Jumping is always mandatory: if a player has the option to jump, they must take it, even if doing so results in disadvantage for the jumping player. For example, a mandated single jump might set up the player such that the opponent has a multi-jump in reply.
722:, world champion from 1955–1962 and from 1975–1991, won a match against the machine in 1992. In 1994, Tinsley had to resign in the middle of an even match for health reasons; he died shortly thereafter. In 1995, Chinook defended its man-machine title against
364:
rule. In this variation jumping is not mandatory, but if a player does not make a jumping move when there is one available to them (either deliberately or by failing to see it), the opponent may declare that the piece that could have made the jump is
736:, Chinook's developers announced that the program had been improved to the point where it could not lose a game. If no mistakes were made by either player, the game would always end in a draw. After eighteen years, they have computationally proven a
424:, and so on. Moves are recorded as "from-to", so a move from 9 to 14 would be recorded 9-14. Captures are notated with an "x" connecting the start and end squares. The game result is often abbreviated as BW/RW (Black/Red wins) or WW (White wins).
407:
There is a standardised notation for recording games. All 32 reachable board squares are numbered in sequence. The numbering starts in Black's double-corner (where Black has two adjacent squares). Black's squares on the first rank are numbered
183:
As in all forms of draughts, English draughts is played by two opponents, alternating turns on opposite sides of the board. The pieces are traditionally black, red, or white. Enemy pieces are captured by jumping over them.
317:
A player wins by capturing all of the opponent's pieces or by leaving the opponent with no legal move. The game is a draw if neither side can force a win, or by agreement (one side offering a draw, the other accepting).
179:
with 12 pieces per side. The pieces move and capture diagonally forward, until they reach the opposite end of the board, when they are crowned and can thereafter move and capture both backward and forward.
851:
305:
If a man moves into the kings row on the opponent's side of the board, it is crowned as a king and gains the ability to move both forward and backward. If a man moves into the kings row or if it
278:
A simple move consists of moving a piece one square diagonally to an adjacent unoccupied dark square. Uncrowned pieces can move diagonally forward only; kings can move in any diagonal direction.
403:
Squares are identified by numbers 1–32. In draughts diagrams, the Black side is typically shown at the top. In printed diagrams, dark and light squares are often reversed for legibility.
644:
247:
Each player starts with 12 men on the dark squares of the three rows closest to that player's side (see diagram). The row closest to each player is called the
297:
chosen is not required to be the one that maximizes the number of jumps in the turn; however, a player must make all available jumps in the sequence chosen.
1274:
609:
From 1840 to 1994, the men's winners were from
Scotland, England, and the United States. From 1994 to 2023, the men's winners were from the United States,
846:
56:
A standard
American Checker Federation (ACF) set: smooth red and white 1.25-inch (32 mm) diameter pieces; green and buff 2-inch (51 mm) squares
1111:
890:
344:
309:
into the kings row, the current move terminates; the piece is crowned as a king but cannot jump back out as in a multi-jump until the next move.
207:
Though pieces are traditionally made of wood, now many are made of plastic, though other materials may be used. Pieces are typically flat and
795:
on both sides, the game will always finish with a draw. However, not all positions that could result from imperfect play have been analysed.
861:
684:(then called the Omniplex) unveiled a new exhibit: Lefty the Checker Playing Robot. Programmed by Scott M Savage, Lefty used an Armdroid
519:
222:. Men are single pieces. Kings consist of two men of the same colour, stacked one on top of the other. The bottom piece is referred to as
659:
647:(NPL), London. Strachey finished the programme, written in his spare time, in February 1951. It ran for the first time on the NPL's
1302:
599:
559:
551:
942:
669:
381:
Capturing with a king precedes capturing with a man. In this case, any available capture can be made at the player's choice.
339:
932:
1307:
523:
1097:
1292:
531:
394:
328:
384:
A man that has jumped to become a king can then in the same turn continue to capture other pieces in a multi-jump.
799:
784:
706:
327:
offered a £100 prize to anybody who could discover a complete game in less than twenty moves. In
February 2003,
841:
681:
257:
1164:
1129:
831:
527:
166:
73:
38:
1297:
1115:
711:
1205:
754:
640:
1078:
673:
1169:
208:
616:
The woman's championship started in 1993. As of 2022, the women's winners have been from
Ireland,
1231:
856:
753:
The number of possible positions in
English draughts is 500,995,484,682,338,672,639 and it has a
737:
715:
192:
1223:
938:
741:
732:
652:
603:
583:
1063:
1213:
1174:
826:
777:
765:
636:
595:
285:
is considered "captured" and removed from the game. Any piece, king or man, can jump a king.
154:
17:
1261:
591:
555:
543:
146:
1268:
1209:
776:
board, the problem of determining if the first player has a win in a given position is
719:
689:
571:
567:
539:
1286:
697:
587:
575:
110:
1235:
1155:
723:
617:
547:
535:
176:
31:
792:
788:
685:
399:
196:
188:
51:
1037:
994:
353:
195:. From the standard starting position, both players can guarantee a draw with
169:
68:
1153:
Schaeffer, Jonathan (2007). "Game over: Black to play and draw in checkers".
1218:
1193:
1064:"Man vs. Machine World Championship: Petal, Mississippi, January 7–17, 1995"
816:
648:
1227:
1178:
606:. Championships are held in GAYP (Go As You Please) and 3-Move versions.
1013:
803:
610:
579:
563:
172:
999:
757:
of approximately 10. By comparison, chess is estimated to have between
651:
computer on 30 July 1951. He soon modified the programme to run on the
621:
627:
The
European Cup has been held since 2013; the World Cup, since 2015.
836:
450:
In Unicode, the draughts are encoded in block Miscellaneous Symbols:
376:
Two common rule variants, not recognised by player associations, are:
258:
239:
1025:
The Proceedings of the Association for Computing Machinery Meeting
821:
758:
693:
668:
398:
338:
238:
976:
958:
913:
1267:
852:
List winners of Czech Republic championship in English draughts
255:. The player with the darker-coloured pieces moves first. Then
1256:
663:
937:. New York: American Sports Publishing Company. p. 15.
522:
in English draughts dates to the 1840s, predating the men's
271:
There are two different ways to move in English draughts:
191:
in 2007 by a team of Canadian computer scientists led by
1251:
995:"PE's Lubabalo Kondlo crowned world draughts champion"
881:
When this word is used in the UK, it is usually spelt
1278:. Vol. 8 (11th ed.). 1911. pp. 547–50.
30:"Chequer" redirects here. For the British actor, see
530:, by several decades. Noted world champions include
1112:"Checkers 'solved' after years of number crunching"
1044:. The Daily Oklahoman. 25 November 1983. p. 51
740:to the game of checkers. Using between two hundred
658:The second computer program was written in 1956 by
117:
106:
98:
90:
82:
61:
1114:. New Scientist. July 19, 2007. Archived from
360:One rule which has fallen out of favor is the
8:
44:
37:"Damka" redirects here. For other uses, see
791:must be understood in the sense that, with
847:List of world championships in mind sports
94:Casual games usually last 10 to 30 minutes
1252:World Checkers Draughts Federation (WCDF)
1217:
1192:Schaeffer, Jonathan (14 September 2007).
1168:
1079:"Computer Checkers Program Is Invincible"
891:American and British spelling differences
730:In July 2007, in an article published in
704:In the 1990s, the strongest program was
432:White resigned after Black's 46th move.
905:
874:
787:'s team stating that the game had been
688:by Colne Robotics and was powered by a
676:'s checkers, 1983, the first robot game
175:(or draughts). It is played on an 8×8
43:
1130:"Chinook - Total Number of Positions"
710:, written in 1989 by a team from the
345:The Children's Museum of Indianapolis
7:
1096:Schmid, Randolph E (July 19, 2007).
862:World Checkers/Draughts Championship
243:The starting setup; Red moves first.
512:
343:Within the permanent collection of
981:World Checkers Draughts Federation
963:World Checkers Draughts Federation
357:is called Go As You Please (GAYP).
25:
1257:American Checker Federation (ACF)
214:There are two classes of pieces:
1262:List of world checkers champions
1077:Chang, Kenneth (July 19, 2007).
934:Checkers: A Treatise on the Game
187:The 8×8 variant of draughts was
50:
798:Some top draughts programs are
768:so that it can be played on an
1098:"Computer can't lose checkers"
959:"Rules of Draughts (Checkers)"
783:The July 2007 announcement by
526:, the championship for men in
1:
645:National Physical Laboratory
931:Cady, Alice Howard (1896).
635:The first English draughts
524:Draughts World Championship
18:American Checker Federation
1324:
613:, South Africa and Italy.
395:Portable Draughts Notation
392:
36:
29:
759:10 and 10 legal positions
49:
842:List of draughts players
749:Computational complexity
1303:Abstract strategy games
1275:Encyclopædia Britannica
1219:10.1126/science.1144079
682:Science Museum Oklahoma
1179:10.3233/ICG-2007-30402
1134:webdocs.cs.ualberta.ca
832:International draughts
692:with a combination of
680:In November 1983, the
677:
528:International draughts
404:
347:
322:Shortest possible game
244:
130:checkers (or chequers)
74:Abstract strategy game
39:Damka (disambiguation)
1118:on December 14, 2007.
712:University of Alberta
672:
402:
342:
242:
1194:"Checkers Is Solved"
977:"Federation-Members"
755:game-tree complexity
662:, a researcher from
641:Christopher Strachey
133:draughts (or drafts)
1210:2007Sci...317.1518S
1204:(5844): 1518–1522.
1042:The Daily Oklahoman
1014:WCDF champions list
920:. 9 September 2021.
506:BLACK DRAUGHTS KING
478:WHITE DRAUGHTS KING
165:, is a form of the
46:
1308:English inventions
1083:The New York Times
983:. 1 December 2019.
889:); see further at
857:Tanzanian draughts
716:Jonathan Schaeffer
678:
520:World Championship
492:BLACK DRAUGHTS MAN
464:WHITE DRAUGHTS MAN
405:
348:
245:
193:Jonathan Schaeffer
1293:Draughts variants
1038:"But Can It Type"
764:When draughts is
742:desktop computers
653:Manchester Mark 1
604:Amangul Durdyyeva
584:Michele Borghetti
235:Starting position
159:straight checkers
140:
139:
127:straight checkers
124:American checkers
16:(Redirected from
1315:
1279:
1271:
1269:"Draughts"
1240:
1239:
1221:
1189:
1183:
1182:
1172:
1150:
1144:
1143:
1141:
1140:
1126:
1120:
1119:
1108:
1102:
1101:
1093:
1087:
1086:
1074:
1068:
1067:
1060:
1054:
1053:
1051:
1049:
1034:
1028:
1027:, Toronto, 1952.
1022:
1016:
1011:
1005:
1004:
991:
985:
984:
973:
967:
966:
955:
949:
948:
928:
922:
921:
914:"Colossus Games"
910:
894:
887:Chinese chequers
879:
778:EXPTIME-complete
733:Science Magazine
637:computer program
631:Computer players
596:Sergio Scarpetta
514:
507:
504:
501:
499:
493:
490:
487:
485:
479:
476:
473:
471:
465:
462:
459:
457:
416:; the next rank
260:
155:American English
143:English draughts
54:
47:
45:English draughts
21:
1323:
1322:
1318:
1317:
1316:
1314:
1313:
1312:
1283:
1282:
1266:
1248:
1243:
1191:
1190:
1186:
1152:
1151:
1147:
1138:
1136:
1128:
1127:
1123:
1110:
1109:
1105:
1095:
1094:
1090:
1076:
1075:
1071:
1062:
1061:
1057:
1047:
1045:
1036:
1035:
1031:
1023:
1019:
1012:
1008:
993:
992:
988:
975:
974:
970:
957:
956:
952:
945:
930:
929:
925:
912:
911:
907:
903:
898:
897:
880:
876:
871:
866:
812:
751:
639:was written by
633:
592:Lubabalo Kondlo
556:Newell W. Banks
544:Robert D. Yates
532:Andrew Anderson
516:
505:
502:
497:
496:
491:
488:
483:
482:
477:
474:
469:
468:
463:
460:
455:
454:
448:
439:
438:
437:
436:
430:
397:
391:
337:
335:Rule variations
324:
315:
303:
269:
262:
237:
232:
205:
157:), also called
147:British English
136:
78:
57:
42:
35:
28:
23:
22:
15:
12:
11:
5:
1321:
1319:
1311:
1310:
1305:
1300:
1295:
1285:
1284:
1281:
1280:
1264:
1259:
1254:
1247:
1246:External links
1244:
1242:
1241:
1184:
1170:10.1.1.154.255
1163:(4): 187–197.
1145:
1121:
1103:
1088:
1069:
1055:
1029:
1017:
1006:
986:
968:
950:
943:
923:
918:Colossus Games
904:
902:
899:
896:
895:
873:
872:
870:
867:
865:
864:
859:
854:
849:
844:
839:
834:
829:
824:
819:
813:
811:
808:
750:
747:
720:Marion Tinsley
690:6502 processor
674:Scott M Savage
643:, M.A. at the
632:
629:
600:Patricia Breen
572:Marion Tinsley
568:Walter Hellman
560:Robert Stewart
540:Robert Martins
515:
510:
509:
508:
494:
480:
466:
447:
444:
443:
442:
429:
426:
393:Main article:
390:
387:
386:
385:
382:
378:
377:
374:
358:
336:
333:
323:
320:
314:
311:
302:
299:
294:Multiple jumps
287:
286:
279:
268:
265:
256:
236:
233:
231:
228:
204:
201:
138:
137:
135:
134:
131:
128:
125:
121:
119:
115:
114:
108:
104:
103:
100:
96:
95:
92:
88:
87:
84:
80:
79:
77:
76:
71:
65:
63:
59:
58:
55:
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
1320:
1309:
1306:
1304:
1301:
1299:
1296:
1294:
1291:
1290:
1288:
1277:
1276:
1270:
1265:
1263:
1260:
1258:
1255:
1253:
1250:
1249:
1245:
1237:
1233:
1229:
1225:
1220:
1215:
1211:
1207:
1203:
1199:
1195:
1188:
1185:
1180:
1176:
1171:
1166:
1162:
1158:
1157:
1149:
1146:
1135:
1131:
1125:
1122:
1117:
1113:
1107:
1104:
1099:
1092:
1089:
1084:
1080:
1073:
1070:
1065:
1059:
1056:
1043:
1039:
1033:
1030:
1026:
1021:
1018:
1015:
1010:
1007:
1002:
1001:
996:
990:
987:
982:
978:
972:
969:
964:
960:
954:
951:
946:
940:
936:
935:
927:
924:
919:
915:
909:
906:
900:
892:
888:
884:
878:
875:
868:
863:
860:
858:
855:
853:
850:
848:
845:
843:
840:
838:
835:
833:
830:
828:
825:
823:
820:
818:
815:
814:
809:
807:
805:
801:
796:
794:
790:
786:
781:
779:
775:
771:
767:
762:
760:
756:
748:
746:
743:
739:
738:weak solution
735:
734:
728:
725:
721:
717:
713:
709:
708:
702:
699:
698:Assembly code
695:
691:
687:
683:
675:
671:
667:
665:
661:
660:Arthur Samuel
656:
654:
650:
646:
642:
638:
630:
628:
625:
623:
619:
614:
612:
607:
605:
601:
597:
593:
589:
588:Alex Moiseyev
585:
581:
577:
576:Derek Oldbury
573:
569:
565:
561:
557:
553:
552:Alfred Jordan
549:
545:
541:
537:
533:
529:
525:
521:
511:
495:
481:
467:
453:
452:
451:
445:
435:
434:
433:
427:
425:
423:
419:
415:
411:
401:
396:
388:
383:
380:
379:
375:
372:
368:
363:
359:
355:
350:
349:
346:
341:
334:
332:
330:
329:Martin Bryant
321:
319:
312:
310:
308:
300:
298:
295:
291:
283:
280:
277:
274:
273:
272:
266:
264:
261:
254:
250:
241:
234:
229:
227:
225:
221:
217:
212:
210:
202:
200:
198:
194:
190:
189:weakly solved
185:
181:
178:
174:
171:
168:
164:
160:
156:
152:
148:
144:
132:
129:
126:
123:
122:
120:
116:
112:
109:
105:
101:
97:
93:
89:
85:
81:
75:
72:
70:
67:
66:
64:
60:
53:
48:
40:
33:
19:
1298:Solved games
1273:
1201:
1197:
1187:
1160:
1156:ICGA Journal
1154:
1148:
1137:. Retrieved
1133:
1124:
1116:the original
1106:
1100:. USA Today.
1091:
1082:
1072:
1058:
1046:. Retrieved
1041:
1032:
1024:
1020:
1009:
998:
989:
980:
971:
962:
953:
933:
926:
917:
908:
886:
882:
877:
797:
793:perfect play
782:
773:
769:
763:
752:
731:
729:
724:Don Lafferty
705:
703:
679:
657:
634:
626:
618:Turkmenistan
615:
608:
548:James Ferrie
536:James Wyllie
517:
449:
431:
421:
417:
413:
409:
406:
370:
366:
361:
325:
316:
306:
304:
293:
292:
288:
281:
276:Simple move:
275:
270:
252:
248:
246:
223:
219:
215:
213:
206:
197:perfect play
186:
182:
177:checkerboard
162:
158:
150:
142:
141:
91:Playing time
32:Paul Chequer
766:generalized
686:robotic arm
428:Sample game
313:End of game
263:alternate.
209:cylindrical
1287:Categories
1139:2017-11-18
1066:. Chinook.
944:1340551446
901:References
655:computer.
518:The men's
267:Move rules
170:board game
161:or simply
69:Board game
27:Board game
1165:CiteSeerX
827:High jump
817:Alquerque
649:Pilot ACE
253:crownhead
249:kings row
113:, tactics
1236:10274228
1228:17641166
1048:26 March
883:chequers
810:See also
804:KingsRow
611:Barbados
580:Ron King
564:Asa Long
503:⛃
489:⛂
475:⛁
461:⛀
389:Notation
173:checkers
167:strategy
163:draughts
151:checkers
118:Synonyms
111:Strategy
1206:Bibcode
1198:Science
1000:YouTube
965:. 2012.
885:(as in
800:Chinook
785:Chinook
714:led by
707:Chinook
622:Ukraine
446:Unicode
362:huffing
224:crowned
83:Players
1234:
1226:
1167:
941:
837:Konane
802:, and
789:solved
745:play.
620:, and
602:, and
500:
498:U+26C3
486:
484:U+26C2
472:
470:U+26C1
458:
456:U+26C0
371:huffed
203:Pieces
107:Skills
99:Chance
62:Genres
1232:S2CID
869:Notes
822:Dameo
694:BASIC
513:Sport
367:blown
354:draws
307:jumps
301:Kings
282:Jump:
259:turns
230:Rules
220:kings
149:) or
1224:PMID
1050:2022
939:ISBN
696:and
218:and
102:None
1214:doi
1202:317
1175:doi
664:IBM
420:to
412:to
369:or
251:or
216:men
1289::
1272:.
1230:.
1222:.
1212:.
1200:.
1196:.
1173:.
1161:30
1159:.
1132:.
1081:.
1040:.
997:.
979:.
961:.
916:.
806:.
780:.
761:.
718:.
624:.
598:,
594:,
590:,
586:,
582:,
578:,
574:,
570:,
566:,
562:,
558:,
554:,
550:,
546:,
542:,
538:,
534:,
199:.
1238:.
1216::
1208::
1181:.
1177::
1142:.
1085:.
1052:.
1003:.
947:.
893:.
774:n
772:×
770:m
422:8
418:5
414:4
410:1
153:(
145:(
86:2
41:.
34:.
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
