Daily Galaxy New Coverage (CLPFD)

news.pl

:-use_module(library(clpfd)).

reporters(["Corey", "Jimmy", "Lois", "Perry"]).
locations(["Bayonne", "New Hope", "Port Charles", "South Amboy"]).
events(["30-pound baby", "blimp launching", "skyscraper dedication", "beached whale"]).

match():-
    reporters(R), length(R, N), length(L, N), length(E, N),
    L ins 1..4, E ins 1..4, all_distinct(L), all_distinct(E),
% 1. Reporter of event 1 didn't go to location 2 or 4
    element(R1X, E, 1), element(R1Y, L, 2), element(R1Z, L, 4), R1X #\= R1Y, R1X #\= R1Z,
% 2. Reporter 2 didn't go to location 3
    element(2, L, L2), L2 #\= 3,
% 3. Events 2 and 3 were covered by reporter 3 and the reporter in location 3
    element(3, E, E3X), element(R3, L, 3), element(R3, E, E3Y), E3X in 2..3,
    E3X #= 2 #==> E3Y #= 3, E3X #= 3 #==> E3Y #= 2,
% 4. Events 3 and 4 were not at location 4
    element(R4X, E, 3), element(R4Y, E, 4), element(R4Z, L, 4), R4X #\= R4Z, R4Y #\= R4Z,
% 5. Reporter 1 went to location 1 OR event 4 was at location 1
    element(R5X, L, 1), element(R5Y, E, 4), element(R5Y, L, L5),
    R5X #\= 1 #==> L5 #= 1, L5 #\= 1 #==> R5X #==> 1,
    maplist(label, [L, E]), maplist(match, R, L, E).

match(R, L, E):-
    locations(Ls), events(Es),
    nth1(L, Ls, Loc), nth1(E, Es, Ev),
    format("~w covered ~w at ~w~n", [R, Ev, Loc]).