man(brian; joe; chris; bob).
professor(brian; joe).
phd(chris).
asisstant(bob).

lesson(1..10).
day(1..5).
week(even; odd).

course(a;b;c;d;e;f;j;h;k;l;m;n).

time(a, 10).
time(b, 12).
time(c, 20).
time(d, 3).
time(e, 17).
time(f, 15).
time(j, 9).
time(h, 7).
time(k, 11).
time(l, 14).
time(m, 8).
time(n, 17).

room(402; 403; 404).

course_room(a, 402).
course_room(c, 404).
course_room(d, 403).
course_room(d, 404).

%               ----   timetable(Teacher, Course, Lesson, Room, Day, Week)



 timetable(brian, a, 1, 402, 1, even).
 timetable(brian, a, 3, 402, 1, even).
 timetable(brian, a, 4, 402, 1, even).
 
 owl(joe)  % no first lesson
 :- owl(T); timetable(T, _, 1,_, _, _).
 
earlybird(bob).
earlybird_score(T, Score) :- Score = #count {timetable(T, C, 1, R, D, W): course(C), room(R), day(D), week(W)}; earlybird(T)  .
earlybird_score(Score) :- Score = #sum{Score2, 1: earlybird_score(T, Score2)}.
:- earlybird_score(X); X<2.


courseDuration(C, Span) :- Span = #count{(T, C, L, R, D, W):timetable(T, C, L, R, D, W), man(T), room(R), day(D), week(W), lesson(L)};course(C).     




#show courseDuration/2.