Exercises.dl

person('Charles',1945,m).
person('Anne',1950,f).
person('Andrew',1960,m).
person('Edward',1964,m).
person('Diana',1961,f).
person('Camilla',1947,f).
person('William',1982,m).
person('Henry',1984,m).
person('Mark',1948,m).
person('Timothy',1950,m).
person('Sarah',1959,f).
person('Sophie',1965,f).
person('Peter',1977,m).
person('Zara',1981,f).
person('Louise',2003,f).
person('James',2007,m).
person('Beatrice',1988,f).
person('Eugenie',1990,f).
person('Catherine',1982,f).
person('Autumn',1978,f).
person('Savannah',2010,f).
person('George',2013,m).
person('Michael',1973,m).
person('Isla',2010,f).
person('Mancer',2017,m).

child('Philip','Elizabeth II','Charles').
child('Philip','Elizabeth II','Anne').
child('Philip','Elizabeth II','Andrew').
child('Philip','Elizabeth II','Edward').
child('Charles','Diana','William').
child('Charles','Diana','Henry').
child('Mark','Anne','Peter').
child('Mark','Anne','Zara').
child('Edward','Sophie','Louise').
child('Edward','Sophie','James').
child('Andrew','Sarah','Beatrice').
child('Andrew','Sarah','Eugenie').
child('Peter','Autumn','Savannah').
child('William','Kate','George').
child('Peter','Autumn','Isla').
child('Charles','Camilla','Mancer').

death('Diana',1997).

marriage('Philip','Elizabeth II',1947).
marriage('Mark','Anne',1973).
marriage('Timothy','Anne',1992).
marriage('Charles','Diana',1981).
marriage('Charles','Camilla',2005).
marriage('Andrew','Sarah',1986).
marriage('Edward','Sophie',1999).
marriage('William','Catherine',2011).
marriage('Michael','Zara',2011).

divorce('Mark','Anne',1992).
divorce('Charles','Diana',1996).
divorce('Andrew','Sarah',1996).

father(F,C):-child(F,_,C).
mother(M,C):-child(_,M,C).


parent(P,C):-father(P,C).
parent(P,C):-mother(P,C).

male(P):-person(P,_,m).

son(P,C):-parent(P,C),male(C).

halfbrother(HB,Person):-son(P,HB),father(P,Person),mother(M,Person), not mother(M,HB).
halfbrother(HB,Person):-son(P,HB),mother(P,Person),father(M,Person), not father(M,HB).