:- use_module(library(clpfd)). different_lists([A|TA], [B|TB]) :- ( A #\= B ; different_lists(TA, TB)). all_different_lists([]). all_different_lists([A|T]) :- all_different_lists(T, A), all_different_lists(T). all_different_lists([], _). all_different_lists([B|T], A) :- different_lists(A, B), all_different_lists(T, A). solve([Row1, Row2, Row3, Row4, Row5, Row6, Row7]) :- Row1 = [A1, A2, A3, A4, A5, A6, A7], Row2 = [B1, B2, B3, B4, B5, B6, B7], Row3 = [C1, C2, C3, C4, C5, C6, C7], Row4 = [D1, D2, D3, D4, D5, D6, D7], Row5 = [E1, E2, E3, E4, E5, E6, E7], Row6 = [F1, F2, F3, F4, F5, F6, F7], Row7 = [G1, G2, G3, G4, G5, G6, G7], Col1 = [A1, B1, C1, D1, E1, F1, G1], Col2 = [A2, B2, C2, D2, E2, F2, G2], Col3 = [A3, B3, C3, D3, E3, F3, G3], Col4 = [A4, B4, C4, D4, E4, F4, G4], Col5 = [A5, B5, C5, D5, E5, F5, G5], Col6 = [A6, B6, C6, D6, E6, F6, G6], Col7 = [A7, B7, C7, D7, E7, F7, G7], Row1 = [0, 0, 1, 1, 2, 2, 2], Col1 = [0, 0, 1, 1, 2, 2, 2], global_cardinality(Row2, [0-2, 1-2, 2-3]), global_cardinality(Row3, [0-2, 1-2, 2-3]), global_cardinality(Row4, [0-2, 1-2, 2-3]), global_cardinality(Row5, [0-2, 1-2, 2-3]), global_cardinality(Row6, [0-2, 1-2, 2-3]), global_cardinality(Row7, [0-2, 1-2, 2-3]), global_cardinality(Col2, [0-2, 1-2, 2-3]), global_cardinality(Col3, [0-2, 1-2, 2-3]), global_cardinality(Col4, [0-2, 1-2, 2-3]), global_cardinality(Col5, [0-2, 1-2, 2-3]), global_cardinality(Col6, [0-2, 1-2, 2-3]), global_cardinality(Col7, [0-2, 1-2, 2-3]), all_different_lists([Row1, Row2, Row3, Row4, Row5, Row6, Row7]), all_different_lists([Col1, Col2, Col3, Col4, Col5, Col6, Col7]), label([A1, A2, A3, A4, A5, A6, A7, B1, B2, B3, B4, B5, B6, B7, C1, C2, C3, C4, C5, C6, C7, D1, D2, D3, D4, D5, D6, D7, E1, E2, E3, E4, E5, E6, E7, F1, F2, F3, F4, F5, F6, F7, G1, G2, G3, G4, G5, G6, G7]). :- writeln('searching...'). :- time(solve(S)), writeln(S). #### ?- [g]. searching... % 9,048,776 inferences, 5.100 CPU in 5.109 seconds (100% CPU, 1774270 Lips) [[0, 0, 1, 1, 2, 2, 2], [0, 2, 1, 2, 0, 1, 2], [1, 1, 0, 0, 2, 2, 2], [1, 2, 0, 0, 2, 2, 1], [2, 0, 2, 2, 0, 1, 1], [2, 1, 2, 2, 1, 0, 0], [2, 2, 2, 1, 1, 0, 0]] % g compiled 5.10 sec, 832 bytes true.