1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
# coding=utf-8 id = 101 group = 'family_relations' number = 8 visible = True facts = 'family_relations' solution = '''\ descendant(X, Y) :- parent(Y, X). descendant(X, Y) :- parent(Y, Z), descendant(X, Z). '''