jeremyhuiskamp

jeremyhuiskamp

Programmer Passport: Prolog: apply_constraints checks morning game twice (page 60)

In this code:

apply_constraints(MatchA, MatchB, PotentialMatches, RemainingMatches, Day) :-
    different_teams(MatchA, MatchB),
    can_play(MatchA, morning, Day),
    can_play(MatchB, morning, Day),
    subtract(PotentialMatches, [MatchA, MatchB], RemainingMatches).

the second can_play clause should be checking the afternoon rather than the morning. This would be more obvious if the games were called MorningMatch and AfternoonMatch rather than MatchA and MatchB.

First Post!

Jimmysnielsen

Jimmysnielsen

@redrapids

on a similar note here, the cant_play restrictions should have their team names in quotes :
cant_play(“comets”, morning, “July 2”).
cant_play(“stars”, afternoon, “July 23”)

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