MAYBE
0.18/0.21	MAYBE
0.18/0.21	
0.18/0.21	Problem:
0.18/0.21	 active(app(nil(),YS)) -> mark(YS)
0.18/0.21	 active(app(cons(X,XS),YS)) -> mark(cons(X,app(XS,YS)))
0.18/0.21	 active(from(X)) -> mark(cons(X,from(s(X))))
0.18/0.21	 active(zWadr(nil(),YS)) -> mark(nil())
0.18/0.21	 active(zWadr(XS,nil())) -> mark(nil())
0.18/0.21	 active(zWadr(cons(X,XS),cons(Y,YS))) -> mark(cons(app(Y,cons(X,nil())),zWadr(XS,YS)))
0.18/0.21	 active(prefix(L)) -> mark(cons(nil(),zWadr(L,prefix(L))))
0.18/0.21	 active(app(X1,X2)) -> app(active(X1),X2)
0.18/0.21	 active(app(X1,X2)) -> app(X1,active(X2))
0.18/0.21	 active(cons(X1,X2)) -> cons(active(X1),X2)
0.18/0.21	 active(from(X)) -> from(active(X))
0.18/0.21	 active(s(X)) -> s(active(X))
0.18/0.21	 active(zWadr(X1,X2)) -> zWadr(active(X1),X2)
0.18/0.21	 active(zWadr(X1,X2)) -> zWadr(X1,active(X2))
0.18/0.21	 active(prefix(X)) -> prefix(active(X))
0.18/0.21	 app(mark(X1),X2) -> mark(app(X1,X2))
0.18/0.21	 app(X1,mark(X2)) -> mark(app(X1,X2))
0.18/0.21	 cons(mark(X1),X2) -> mark(cons(X1,X2))
0.18/0.21	 from(mark(X)) -> mark(from(X))
0.18/0.21	 s(mark(X)) -> mark(s(X))
0.18/0.21	 zWadr(mark(X1),X2) -> mark(zWadr(X1,X2))
0.18/0.21	 zWadr(X1,mark(X2)) -> mark(zWadr(X1,X2))
0.18/0.21	 prefix(mark(X)) -> mark(prefix(X))
0.18/0.21	 proper(app(X1,X2)) -> app(proper(X1),proper(X2))
0.18/0.21	 proper(nil()) -> ok(nil())
0.18/0.21	 proper(cons(X1,X2)) -> cons(proper(X1),proper(X2))
0.18/0.21	 proper(from(X)) -> from(proper(X))
0.18/0.21	 proper(s(X)) -> s(proper(X))
0.18/0.21	 proper(zWadr(X1,X2)) -> zWadr(proper(X1),proper(X2))
0.18/0.21	 proper(prefix(X)) -> prefix(proper(X))
0.18/0.21	 app(ok(X1),ok(X2)) -> ok(app(X1,X2))
0.18/0.21	 cons(ok(X1),ok(X2)) -> ok(cons(X1,X2))
0.18/0.21	 from(ok(X)) -> ok(from(X))
0.18/0.21	 s(ok(X)) -> ok(s(X))
0.18/0.21	 zWadr(ok(X1),ok(X2)) -> ok(zWadr(X1,X2))
0.18/0.21	 prefix(ok(X)) -> ok(prefix(X))
0.18/0.21	 top(mark(X)) -> top(proper(X))
0.18/0.21	 top(ok(X)) -> top(active(X))
0.18/0.21	
0.18/0.21	Proof:
0.18/0.21	 Open
0.18/0.21	EOF