solution([]).
solution([ X/Y | Others ] ) :- solution( Others ),
                               member( Y, [1,2,3,4,5,6,7,8] ),
                               noattack( X/Y, Others ).

noattack( _ , [] ).
noattack( X/Y, [ X1/Y1 | Others ] ) :- Y =\= Y1,
                                       Y1-Y =\= X1-X,
                                       Y1-Y =\= X-X1,
                                       noattack( X/Y, Others ).

template([1/Y1, 2/Y2, 3/Y3, 4/Y4, 5/Y5, 6/Y6, 7/Y7, 8/Y8]).