Prologの技芸 2.2節の練習問題

サンプルデータベース

day(complexity,monday).
start_time(complexity,9).
finish_time(complexity,11).
lecturer(complexity,harel).
building(complexity,feinberg).
room(complexity,a).

(1)

location(Course,Building) :-
 building(Course,Building).
busy(Lecturer,Time) :-
 lecturer(Course,Lecturer),
 start_time(Course,Start), finish_time(Course,Finish), 
 Start =< Time, Time =< Finish.
cannot_meet(Lecturer1,Lecturer2) :-
 lecturer(Course1,Lecturer1), lecturer(Course2,Lecturer2),
 Course1 \= Course2.

(2)

schedule_conflict(Time,Place,Course1,Course2) :-
 building(Course1,Building), building(Course2,Building),
 room(Course1,Room), room(Course2,Room),
 start_time(Course1,Start1), finish_time(Course1,Finish1), 
 start_time(Course2,Start2), finish_time(Course2,Finish2).
 Start1 =< Finish2, Start2 =< Finish1,
 Start1 =< Time, Time =< Finish1,
 Start2 =< Time, Time =< Finish2.