# coding=utf-8 id = 99 group = 'family_relations' number = 6 visible = True facts = 'family_relations' solution = '''\ sister99(X, Y) :- parent(P, X), parent(P, Y), female(X), X \== Y. brother99(X, Y) :- parent(P, X), parent(P, Y), male(X), X \== Y. cousin(X, Y) :- parent(PX, X), parent(PY, Y), ( brother99(PX, PY) ; sister99(PX, PY) ). '''