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  1. :- set_prolog_flag(verbose,silent).
  2. :- prompt(_, '').
  3. :- use_module(library(readutil)).
  4.  
  5.  
  6.      byCar(auckland,hamilton).  
  7.        byCar(hamilton,raglan).  
  8.        byCar(valmont,saarbruecken).  
  9.        byCar(valmont,metz).  
  10.  
  11.        byTrain(metz,frankfurt).  
  12.        byTrain(saarbruecken,frankfurt).  
  13.        byTrain(metz,paris).  
  14.        byTrain(saarbruecken,paris).  
  15.  
  16.        byPlane(frankfurt,bangkok).  
  17.        byPlane(frankfurt,singapore).  
  18.        byPlane(paris,losAngeles).  
  19.        byPlane(bangkok,auckland).  
  20.        byPlane(singapore,auckland).  
  21.        byPlane(losAngeles,auckland). 
  22.  
  23. travel(X,Y) :- byCar(X,Y); byTrain(X,Y); byPlane(X,Y).
  24.  
  25.  
  26. travel(X,X,Visited,end) :- !.
  27. travel(X,Y,Visited,Path) :-
  28.   \+ member(X, Visited),
  29.   travel(X, New),
  30.   travel(New, Y, [ X | Visited ], Path1),
  31.   ( Path1 = end ->
  32.     Path = go(X, New)
  33.   ; Path = go(X, New, Path1) ).
  34.  
  35. travel(X,Y,Path) :-
  36.   travel(X,Y,[],Path).
  37.  
  38. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  39.  
  40. main:-
  41. 	process,
  42. 	halt.
  43.  
  44. process:-
  45. 	/* your code goes here */
  46. 	findall(X, travel(valmont,losAngeles,X), L),
  47. 	write(L),
  48. 	true.
  49.  
  50. :- main.
  51.  
  52. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  53.  
Success #stdin #stdout #stderr 0.03s 6160KB
comments (?)
stdin 
Standard input is empty
stdout 
[go(valmont, saarbruecken, go(saarbruecken, paris, go(paris, losAngeles))), go(valmont, metz, go(metz, paris, go(paris, losAngeles)))]
stderr 
Warning: /home/k1vGsA/prog.pl:26:
	Singleton variables: [Visited]
https://ideone.com/GfQu3O
language:
Prolog (swi 7.6.4)
created:
11 years ago
visibility:
public

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