% Define p(M2, M4) :- M1 = 1..4, M2 = 2 * M1, M4 = 4 * M1. q(M1, S) :- M1 = 0..4, S = -1 ** M1. l(K, I) :- K = 1..4, I = 1..K. r(1..2,1..4). r(1..4,1..2).