Could someone please explain how this code works

Help!
,
1

Im working on solving a task, where i have to walk thorugh a labyrinth with doors to get to a specific room and i have to find out the way. I created this program with help but don’t quite understand it, could someone please do so?

(tuer=door; richtung=direction/arrow; weg=the path; Start/Ende=start/end; Loesung=solution; Punkt =Point, Knot)

tuer(a,b).
tuer(b,e).
tuer(b,c).
tuer(d,e).
tuer(c,d).
tuer(e,f). 
tuer(g,e).

richtung(X, Y):-tuer (X,Y). 
richtung(X,Y):-tuer (Y, X).

%Now is the point of not understanding anything
weg(Start,Ziel, Loesung): -richtung (Start, X), richtung (Y, Ziel),
                                              weg (Start, [Start], Ziel, Loesung).

weg(Ziel, Weg,Ziel, Loesung):-Loesung = Weg.

weg(PunktA, Weg, Ziel, Loesung):-
         richtung (PunktA, PunktX),
         \+(member(PunktX, Weg)), 
          append(Weg, [PunktX], WegNeu),
          weg (PunktX, WegNeu, Ziel, Loesung).

Thank you in advance!

2

Also asked at prolog - Could someone please explain how this code works - Stack Overflow

3

Only you know why you don’t understand something. Anyway- something that always works in situations like this is prolog’s trace facility. Google it, use it, follow it. Don’t expect shortcuts.

4

While you can ask these type of homework questions here, do not expect an answer here.

To get started learning Prolog please use one of the free introduction books. :slightly_smiling_face:

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