Showing how to find sum of two sets
Source: PROLOG str. 190 Wydawnictwo PLJ Warszawa 1991 ISBN 83-85190-63-5
Program source code: sets_sum.pl
suma([], X, X). suma([X|R], Y, Z) :- member(X, Y), !, suma(R, Y, Z). suma([X|R], Y, [X|Z]) :- suma(R, Y, Z). test :- suma([1, 2, 3], [2, 4], C).