如果您使用 CLP(FD) 对整数进行推理,并更改约束的顺序以便在递归之前约束计数器,这将消除您的循环问题:
move([X, Y], [A, B]) :- X + 1 #< 8, Y + 2 #< 8, A #= X + 1, B #= Y + 2.
move([X, Y], [A, B]) :- X + 2 #< 8, Y + 1 #< 8, A #= X + 2, B #= Y + 1.
move([X, Y], [A, B]) :- X + 2 #< 8, Y - 1 #>= 0, A #= X + 2, B #= Y - 1.
move([X, Y], [A, B]) :- X + 1 #< 8, Y - 2 #>= 0, A #= X + 1, B #= Y - 2.
move([X, Y], [A, B]) :- X - 1 #>= 0, Y - 2 #>= 0, A #= X - 1, B #= Y - 2.
move([X, Y], [A, B]) :- X - 2 #>= 0, Y - 1 #>= 0, A #= X - 2, B #= Y - 1.
move([X, Y], [A, B]) :- X - 2 #>= 0, Y + 1 #< 8, A #= X - 2, B #= Y + 1.
move([X, Y], [A, B]) :- X - 1 #>= 0, Y + 2 #< 8, A #= X - 1, B #= Y + 2.
knight_move(X,Y,[X,Y], 1) :- move(X,Y).
# NOTE the constraint of C #= Cn + 1 before the recursive call
knight_move(X,Y,[X|P], C) :- C #> 1, move(X,Z), C #= Cn + 1, knight_move(Z,Y,P,Cn).
predict_moves(X,C,P) :- knight_move(X,_,P,C).
结果是:
| ?- predict_moves([1,1], 3, P).
P = [[1,1],[2,3],[3,5],[4,7]] ? a
P = [[1,1],[2,3],[3,5],[5,6]]
P = [[1,1],[2,3],[3,5],[5,4]]
P = [[1,1],[2,3],[3,5],[4,3]]
P = [[1,1],[2,3],[3,5],[2,3]]
P = [[1,1],[2,3],[3,5],[1,4]]
P = [[1,1],[2,3],[3,5],[1,6]]
P = [[1,1],[2,3],[3,5],[2,7]]
P = [[1,1],[2,3],[4,4],[5,6]]
P = [[1,1],[2,3],[4,4],[6,5]]
P = [[1,1],[2,3],[4,4],[6,3]]
P = [[1,1],[2,3],[4,4],[5,2]]
P = [[1,1],[2,3],[4,4],[3,2]]
P = [[1,1],[2,3],[4,4],[2,3]]
P = [[1,1],[2,3],[4,4],[2,5]]
P = [[1,1],[2,3],[4,4],[3,6]]
P = [[1,1],[2,3],[4,2],[5,4]]
P = [[1,1],[2,3],[4,2],[6,3]]
P = [[1,1],[2,3],[4,2],[6,1]]
P = [[1,1],[2,3],[4,2],[5,0]]
P = [[1,1],[2,3],[4,2],[3,0]]
P = [[1,1],[2,3],[4,2],[2,1]]
P = [[1,1],[2,3],[4,2],[2,3]]
P = [[1,1],[2,3],[4,2],[3,4]]
P = [[1,1],[2,3],[3,1],[4,3]]
P = [[1,1],[2,3],[3,1],[5,2]]
P = [[1,1],[2,3],[3,1],[5,0]]
P = [[1,1],[2,3],[3,1],[1,0]]
P = [[1,1],[2,3],[3,1],[1,2]]
P = [[1,1],[2,3],[3,1],[2,3]]
P = [[1,1],[2,3],[1,1],[2,3]]
P = [[1,1],[2,3],[1,1],[3,2]]
P = [[1,1],[2,3],[1,1],[3,0]]
P = [[1,1],[2,3],[1,1],[0,3]]
P = [[1,1],[2,3],[0,2],[1,4]]
P = [[1,1],[2,3],[0,2],[2,3]]
P = [[1,1],[2,3],[0,2],[2,1]]
P = [[1,1],[2,3],[0,2],[1,0]]
P = [[1,1],[2,3],[0,4],[1,6]]
P = [[1,1],[2,3],[0,4],[2,5]]
P = [[1,1],[2,3],[0,4],[2,3]]
P = [[1,1],[2,3],[0,4],[1,2]]
P = [[1,1],[2,3],[1,5],[2,7]]
P = [[1,1],[2,3],[1,5],[3,6]]
P = [[1,1],[2,3],[1,5],[3,4]]
P = [[1,1],[2,3],[1,5],[2,3]]
P = [[1,1],[2,3],[1,5],[0,3]]
P = [[1,1],[2,3],[1,5],[0,7]]
P = [[1,1],[3,2],[4,4],[5,6]]
P = [[1,1],[3,2],[4,4],[6,5]]
P = [[1,1],[3,2],[4,4],[6,3]]
P = [[1,1],[3,2],[4,4],[5,2]]
P = [[1,1],[3,2],[4,4],[3,2]]
P = [[1,1],[3,2],[4,4],[2,3]]
P = [[1,1],[3,2],[4,4],[2,5]]
P = [[1,1],[3,2],[4,4],[3,6]]
P = [[1,1],[3,2],[5,3],[6,5]]
P = [[1,1],[3,2],[5,3],[7,4]]
P = [[1,1],[3,2],[5,3],[7,2]]
P = [[1,1],[3,2],[5,3],[6,1]]
P = [[1,1],[3,2],[5,3],[4,1]]
P = [[1,1],[3,2],[5,3],[3,2]]
P = [[1,1],[3,2],[5,3],[3,4]]
P = [[1,1],[3,2],[5,3],[4,5]]
P = [[1,1],[3,2],[5,1],[6,3]]
P = [[1,1],[3,2],[5,1],[7,2]]
P = [[1,1],[3,2],[5,1],[7,0]]
P = [[1,1],[3,2],[5,1],[3,0]]
P = [[1,1],[3,2],[5,1],[3,2]]
P = [[1,1],[3,2],[5,1],[4,3]]
P = [[1,1],[3,2],[4,0],[5,2]]
P = [[1,1],[3,2],[4,0],[6,1]]
P = [[1,1],[3,2],[4,0],[2,1]]
P = [[1,1],[3,2],[4,0],[3,2]]
P = [[1,1],[3,2],[2,0],[3,2]]
P = [[1,1],[3,2],[2,0],[4,1]]
P = [[1,1],[3,2],[2,0],[0,1]]
P = [[1,1],[3,2],[2,0],[1,2]]
P = [[1,1],[3,2],[1,1],[2,3]]
P = [[1,1],[3,2],[1,1],[3,2]]
P = [[1,1],[3,2],[1,1],[3,0]]
P = [[1,1],[3,2],[1,1],[0,3]]
P = [[1,1],[3,2],[1,3],[2,5]]
P = [[1,1],[3,2],[1,3],[3,4]]
P = [[1,1],[3,2],[1,3],[3,2]]
P = [[1,1],[3,2],[1,3],[2,1]]
P = [[1,1],[3,2],[1,3],[0,1]]
P = [[1,1],[3,2],[1,3],[0,5]]
P = [[1,1],[3,2],[2,4],[3,6]]
P = [[1,1],[3,2],[2,4],[4,5]]
P = [[1,1],[3,2],[2,4],[4,3]]
P = [[1,1],[3,2],[2,4],[3,2]]
P = [[1,1],[3,2],[2,4],[1,2]]
P = [[1,1],[3,2],[2,4],[0,3]]
P = [[1,1],[3,2],[2,4],[0,5]]
P = [[1,1],[3,2],[2,4],[1,6]]
P = [[1,1],[3,0],[4,2],[5,4]]
P = [[1,1],[3,0],[4,2],[6,3]]
P = [[1,1],[3,0],[4,2],[6,1]]
P = [[1,1],[3,0],[4,2],[5,0]]
P = [[1,1],[3,0],[4,2],[3,0]]
P = [[1,1],[3,0],[4,2],[2,1]]
P = [[1,1],[3,0],[4,2],[2,3]]
P = [[1,1],[3,0],[4,2],[3,4]]
P = [[1,1],[3,0],[5,1],[6,3]]
P = [[1,1],[3,0],[5,1],[7,2]]
P = [[1,1],[3,0],[5,1],[7,0]]
P = [[1,1],[3,0],[5,1],[3,0]]
P = [[1,1],[3,0],[5,1],[3,2]]
P = [[1,1],[3,0],[5,1],[4,3]]
P = [[1,1],[3,0],[1,1],[2,3]]
P = [[1,1],[3,0],[1,1],[3,2]]
P = [[1,1],[3,0],[1,1],[3,0]]
P = [[1,1],[3,0],[1,1],[0,3]]
P = [[1,1],[3,0],[2,2],[3,4]]
P = [[1,1],[3,0],[2,2],[4,3]]
P = [[1,1],[3,0],[2,2],[4,1]]
P = [[1,1],[3,0],[2,2],[3,0]]
P = [[1,1],[3,0],[2,2],[1,0]]
P = [[1,1],[3,0],[2,2],[0,1]]
P = [[1,1],[3,0],[2,2],[0,3]]
P = [[1,1],[3,0],[2,2],[1,4]]
P = [[1,1],[0,3],[1,5],[2,7]]
P = [[1,1],[0,3],[1,5],[3,6]]
P = [[1,1],[0,3],[1,5],[3,4]]
P = [[1,1],[0,3],[1,5],[2,3]]
P = [[1,1],[0,3],[1,5],[0,3]]
P = [[1,1],[0,3],[1,5],[0,7]]
P = [[1,1],[0,3],[2,4],[3,6]]
P = [[1,1],[0,3],[2,4],[4,5]]
P = [[1,1],[0,3],[2,4],[4,3]]
P = [[1,1],[0,3],[2,4],[3,2]]
P = [[1,1],[0,3],[2,4],[1,2]]
P = [[1,1],[0,3],[2,4],[0,3]]
P = [[1,1],[0,3],[2,4],[0,5]]
P = [[1,1],[0,3],[2,4],[1,6]]
P = [[1,1],[0,3],[2,2],[3,4]]
P = [[1,1],[0,3],[2,2],[4,3]]
P = [[1,1],[0,3],[2,2],[4,1]]
P = [[1,1],[0,3],[2,2],[3,0]]
P = [[1,1],[0,3],[2,2],[1,0]]
P = [[1,1],[0,3],[2,2],[0,1]]
P = [[1,1],[0,3],[2,2],[0,3]]
P = [[1,1],[0,3],[2,2],[1,4]]
P = [[1,1],[0,3],[1,1],[2,3]]
P = [[1,1],[0,3],[1,1],[3,2]]
P = [[1,1],[0,3],[1,1],[3,0]]
P = [[1,1],[0,3],[1,1],[0,3]]
(3 ms) no
| ?-