lich(a;b).
phat(a,thuong,1). phat(a,dieu_chinh_phong,9).
phat(b,thuong,4). phat(b,dieu_chinh_phong,5).
1 { chon(L) : lich(L) } 1.
xau_nhat(M) :- chon(L), M = #max { P,K : phat(L,K,P) }.
#minimize { M : xau_nhat(M) }.
#show chon/1.
#show xau_nhat/1.