:-auto_table.
vegetarian(X) :- meal(X,Y), not nonvegetarian(X).
nonvegetarian(X) :- meal(X,Y), not vegetarian(X).
porc(X) :- nonvegetarian(X), not beef(X), not fish(X).
beef(X) :- nonvegetarian(X), not porc(X), not fish(X).
fish(X) :- nonvegetarian(X), not porc(X), not beef(X).
whitewine(Y) :- meal(X,Y), fish(X).
whitewine(Y) :- meal(X,Y), porc(X).
redwine(Y) :- meal(X,Y), beef(X).
wine(Y) :- redwine(Y).
wine(Y) :- whitewine(Y).
alcoholic(Y) :- wine(Y).
tomatojuice(Y) :- meal(X,Y), vegetarian(X).
meal(a,b).
nonvegetarian(a).