PPT Slide

age(leah, 48) .

age(natalie, 30) .

age(octavia, 34) .

age(darrell, 59) .

age(michael, 8) .

age(sue, 15) .

age(sylvia, 81) .

age(loren, 29) .

age(lura, 87) .

age(ron, 60) .

blond(leah) .

blond(natalie) .

blond(octavia) .

brunette(darrell) .

brunette(michael) .

redhair(sylvia) .

redhair(loren) .

redhair(sue) .

grayhair(lura) .

grayhair(ron) .

cast(X) :- age(X, A) , satisfactory(X, A) .

satisfactory(X, A) :- between(0, 10, A) , !, blond(X) .

satisfactory(X, A) :- between(11, 20, A) , !, redhair(X) .

satisfactory(X, A) :- between(20, 50, A) , !, brunette(X) .

satisfactory(X, A) :- between (50, 90, A) , !, grayhair(X) .

This eliminates some needless search.