Составить запрос. Задача Коммивояжера

e(a,b,3).e(a,c,8).e(a,d,1).e(a,e,5).e(a,f,12).e(a,g,8).e(a,h,4).e(a,i,33).e(a,j,1).
e(b,c,22).e(b,d,45).e(b,e,12).e(b,f,18).e(b,g,76).e(b,h,100).e(b,i,15).e(b,j,91).
e(c,d,17).e(c,e,2).e(c,f,15).e(c,g,4).e(c,h,13).e(c,i,70).e(c,j,81).
e(d,e,36).e(d,f,28).e(d,g,101).e(d,h,22).e(d,i,9).e(d,j,7).
e(e,f,14).e(e,g,31).e(e,h,7).e(e,i,10).e(e,j,5).
e(f,g,1).e(f,h,2).e(f,i,1).e(f,j,100).
e(g,h,33).e(g,i,12).e(g,j,2).
e(h,i,18).e(h,j,71).
e(i,j,6).
 
 
tsp(Towns, _, _):-
  retract_all(bestroute(_)),
 asserta(bestroute(r([], 1000))),
  route(Towns, Route, Distance),
  bestroute(r(_, BestSoFar)),
  Distance < BestSoFar,
  retract(bestroute(r(_, BestSoFar))),
  asserta(bestroute(r(Route, Distance))),
  fail.
tsp(_, Route, Distance):-
  retract(bestroute(r(Route, Distance))), !.
 
route([First|Towns], [First|Route], Distance):-
  route_1(Towns, First, First, 0, Distance, Route).
 
route_1([], Last, First, Distance0, Distance, []):-
distance(Last, First, Distance1),
Distance is Distance0 + Distance1.
 
route_1(Towns0, Town0, First, Distance0, Distance, [Town|Towns]):-
  remove(Town, Towns0, Towns1), 
  distance(Town0, Town, Distance1),
  Distance2 is Distance0 + Distance1,
  route_1(Towns1, Town, First, Distance2, Distance, Towns).
 
%distance(X, Y, D):-X @< Y, !, e(X, Y, D).
%distance(X, Y, D):-e(Y, X, D).
distance(X, Y, D):- e(X, Y, D);e(Y,X,D).
 
retract_all(X):-retract(X), retract_all(X).
retract_all(X).
 
remove(X,[X|Tail],Tail).
remove(X,[Y|Tail],[Y|Tail1]):-remove(X,Tail,Tail1).

?- tsp([a,e],Route,Distance),write(Route).

 e(a,b,3). e(a,c,8). e(a,d,1). e(a,e,5). e(a,f,12). e(a,g,8). e(a,h,4). e(a,i,33). e(a,j,1).
 e(b,c,22). e(b,d,45). e(b,e,12). e(b,f,18). e(b,g,76). e(b,h,100). e(b,i,15). e(b,j,91).
 e(c,d,17). e(c,e,2). e(c,f,15). e(c,g,4). e(c,h,13). e(c,i,70). e(c,j,81).
 e(d,e,36). e(d,f,28). e(d,g,101). e(d,h,22). e(d,i,9). e(d,j,7).
 e(e,f,14). e(e,g,31). e(e,h,7). e(e,i,10). e(e,j,5).
 e(f,g,1). e(f,h,2). e(f,i,1). e(f,j,100).
 e(g,h,33). e(g,i,12). e(g,j,2).
 e(h,i,18). e(h,j,71).
 e(i,j,6).

?- tsp([a,b],Route,Distance),write(Route).