COMMENT  Four Queens - constructed by
COMMENT  Daneel Siddiky

COMMENT  This CSP represents the four queens probem
COMMENT  i.e. Placing 8 queens on a 8x8 chess board 
COMMENT  so none of them can attack each other.

COMMENT  This problem should be solved in a very short
COMMENT  period of time.  It is suitable for use in
COMMENT  AI Practical 2



BeginCSP 8Queens

info (
solubility 1
)

domains 1 (
(1 8 (1 2 3 4 5 6 7 8)
)

variables 8 (
(A 1)
(B 1)
(C 1)
(D 1)
(E 1)
(F 1)
(G 1)
(H 1)
)

constraints 28 (
(A B)
(B C)
(C D)
(D E)
(E F)
(F G)
(G H)
(A C)
(B D)
(C E)
(D F)
(E G)
(F H)
(A D)
(B E)
(C F)
(D G)
(E H)
(A E)
(B F)
(C G)
(D H)
(A F)
(B G)
(C H)
(A G)
(B H)
(A H)
)

conflicts 28 (
((A B) 22 (2 1) (3 2) (4 3) (5 4) (6 5) (7 6) (8 7) (1 2) (2 3) (3 4) (4 5) (5 6) (6 7) (7 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((B C) 22 (2 1) (3 2) (4 3) (5 4) (6 5) (7 6) (8 7) (1 2) (2 3) (3 4) (4 5) (5 6) (6 7) (7 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((C D) 22 (2 1) (3 2) (4 3) (5 4) (6 5) (7 6) (8 7) (1 2) (2 3) (3 4) (4 5) (5 6) (6 7) (7 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((D E) 22 (2 1) (3 2) (4 3) (5 4) (6 5) (7 6) (8 7) (1 2) (2 3) (3 4) (4 5) (5 6) (6 7) (7 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((E F) 22 (2 1) (3 2) (4 3) (5 4) (6 5) (7 6) (8 7) (1 2) (2 3) (3 4) (4 5) (5 6) (6 7) (7 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((F G) 22 (2 1) (3 2) (4 3) (5 4) (6 5) (7 6) (8 7) (1 2) (2 3) (3 4) (4 5) (5 6) (6 7) (7 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((G H) 22 (2 1) (3 2) (4 3) (5 4) (6 5) (7 6) (8 7) (1 2) (2 3) (3 4) (4 5) (5 6) (6 7) (7 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((A C) 20 (3 1) (4 2) (5 3) (6 4) (7 5) (8 6) (1 3) (2 4) (3 5) (4 6) (5 7) (6 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((B D) 20 (3 1) (4 2) (5 3) (6 4) (7 5) (8 6) (1 3) (2 4) (3 5) (4 6) (5 7) (6 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((C E) 20 (3 1) (4 2) (5 3) (6 4) (7 5) (8 6) (1 3) (2 4) (3 5) (4 6) (5 7) (6 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((D F) 20 (3 1) (4 2) (5 3) (6 4) (7 5) (8 6) (1 3) (2 4) (3 5) (4 6) (5 7) (6 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((E G) 20 (3 1) (4 2) (5 3) (6 4) (7 5) (8 6) (1 3) (2 4) (3 5) (4 6) (5 7) (6 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((F H) 20 (3 1) (4 2) (5 3) (6 4) (7 5) (8 6) (1 3) (2 4) (3 5) (4 6) (5 7) (6 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((A D) 18 (4 1) (5 2) (6 3) (7 4) (8 5) (1 4) (2 5) (3 6) (4 7) (5 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8)) 
((B E) 18 (4 1) (5 2) (6 3) (7 4) (8 5) (1 4) (2 5) (3 6) (4 7) (5 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((C F) 18 (4 1) (5 2) (6 3) (7 4) (8 5) (1 4) (2 5) (3 6) (4 7) (5 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((D G) 18 (4 1) (5 2) (6 3) (7 4) (8 5) (1 4) (2 5) (3 6) (4 7) (5 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((E H) 18 (4 1) (5 2) (6 3) (7 4) (8 5) (1 4) (2 5) (3 6) (4 7) (5 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((A E) 16 (5 1) (6 2) (7 3) (8 4) (1 5) (2 6) (3 7) (4 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((B F) 16 (5 1) (6 2) (7 3) (8 4) (1 5) (2 6) (3 7) (4 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((C G) 16 (5 1) (6 2) (7 3) (8 4) (1 5) (2 6) (3 7) (4 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((D H) 16 (5 1) (6 2) (7 3) (8 4) (1 5) (2 6) (3 7) (4 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((A F) 14 (6 1) (7 2) (8 3) (1 6) (2 7) (3 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((B G) 14 (6 1) (7 2) (8 3) (1 6) (2 7) (3 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((C H) 14 (6 1) (7 2) (8 3) (1 6) (2 7) (3 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((A G) 12 (7 1) (8 2) (1 7) (2 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((B H) 12 (7 1) (8 2) (1 7) (2 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
((A H) 10 (8 1) (1 8) (1 1) (2 2) (3 3) (4 4) (5 5) (6 6) (7 7) (8 8))
)

EndCSP 8Queens