% Question 2

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

move([Node|State],[NextNode|State]):-
    child(Node,NextNode),
    \+ member(NextNode,[Node|State]).

goal(Node):- \+ child(Node,_).

visited_df(N,List):-
    solve_depthfirst([N],Path),
    last(Path,[List]).

depthfirst_traversal(N,List):-
    findall(X,visited_df(N,X),List).

visited_bf(N,List):-
    solve_breadthfirst([N],Path),
    last(Path,[List]).

breadthfirst_traversal(N,List):-
    findall(X,visited_bf(N,X),List).