MAYBE
MAYBE
TRS:
 {
                      active(app(X1, X2)) -> app(X1, active(X2)),
                      active(app(X1, X2)) -> app(active(X1), X2),
                   active(app(nil(), YS)) -> mark(YS),
             active(app(cons(X, XS), YS)) -> mark(cons(X, app(XS, YS))),
                     active(cons(X1, X2)) -> cons(active(X1), X2),
                          active(from(X)) -> mark(cons(X, from(s(X)))),
                          active(from(X)) -> from(active(X)),
                             active(s(X)) -> s(active(X)),
                 active(zWadr(XS, nil())) -> mark(nil()),
                    active(zWadr(X1, X2)) -> zWadr(X1, active(X2)),
                    active(zWadr(X1, X2)) -> zWadr(active(X1), X2),
                 active(zWadr(nil(), YS)) -> mark(nil()),
  active(zWadr(cons(X, XS), cons(Y, YS))) ->
  mark(cons(app(Y, cons(X, nil())), zWadr(XS, YS))),
                        active(prefix(X)) -> prefix(active(X)),
                        active(prefix(L)) ->
  mark(cons(nil(), zWadr(L, prefix(L)))),
                        app(X1, mark(X2)) -> mark(app(X1, X2)),
                        app(mark(X1), X2) -> mark(app(X1, X2)),
                      app(ok(X1), ok(X2)) -> ok(app(X1, X2)),
                       cons(mark(X1), X2) -> mark(cons(X1, X2)),
                     cons(ok(X1), ok(X2)) -> ok(cons(X1, X2)),
                            from(mark(X)) -> mark(from(X)),
                              from(ok(X)) -> ok(from(X)),
                               s(mark(X)) -> mark(s(X)),
                                 s(ok(X)) -> ok(s(X)),
                      zWadr(X1, mark(X2)) -> mark(zWadr(X1, X2)),
                      zWadr(mark(X1), X2) -> mark(zWadr(X1, X2)),
                    zWadr(ok(X1), ok(X2)) -> ok(zWadr(X1, X2)),
                          prefix(mark(X)) -> mark(prefix(X)),
                            prefix(ok(X)) -> ok(prefix(X)),
                      proper(app(X1, X2)) -> app(proper(X1), proper(X2)),
                            proper(nil()) -> ok(nil()),
                     proper(cons(X1, X2)) -> cons(proper(X1), proper(X2)),
                          proper(from(X)) -> from(proper(X)),
                             proper(s(X)) -> s(proper(X)),
                    proper(zWadr(X1, X2)) -> zWadr(proper(X1), proper(X2)),
                        proper(prefix(X)) -> prefix(proper(X)),
                             top(mark(X)) -> top(proper(X)),
                               top(ok(X)) -> top(active(X))
 }
 DUP: We consider a duplicating system.
  Trs:
   {
                        active(app(X1, X2)) -> app(X1, active(X2)),
                        active(app(X1, X2)) -> app(active(X1), X2),
                     active(app(nil(), YS)) -> mark(YS),
               active(app(cons(X, XS), YS)) -> mark(cons(X, app(XS, YS))),
                       active(cons(X1, X2)) -> cons(active(X1), X2),
                            active(from(X)) -> mark(cons(X, from(s(X)))),
                            active(from(X)) -> from(active(X)),
                               active(s(X)) -> s(active(X)),
                   active(zWadr(XS, nil())) -> mark(nil()),
                      active(zWadr(X1, X2)) -> zWadr(X1, active(X2)),
                      active(zWadr(X1, X2)) -> zWadr(active(X1), X2),
                   active(zWadr(nil(), YS)) -> mark(nil()),
    active(zWadr(cons(X, XS), cons(Y, YS))) ->
    mark(cons(app(Y, cons(X, nil())), zWadr(XS, YS))),
                          active(prefix(X)) -> prefix(active(X)),
                          active(prefix(L)) ->
    mark(cons(nil(), zWadr(L, prefix(L)))),
                          app(X1, mark(X2)) -> mark(app(X1, X2)),
                          app(mark(X1), X2) -> mark(app(X1, X2)),
                        app(ok(X1), ok(X2)) -> ok(app(X1, X2)),
                         cons(mark(X1), X2) -> mark(cons(X1, X2)),
                       cons(ok(X1), ok(X2)) -> ok(cons(X1, X2)),
                              from(mark(X)) -> mark(from(X)),
                                from(ok(X)) -> ok(from(X)),
                                 s(mark(X)) -> mark(s(X)),
                                   s(ok(X)) -> ok(s(X)),
                        zWadr(X1, mark(X2)) -> mark(zWadr(X1, X2)),
                        zWadr(mark(X1), X2) -> mark(zWadr(X1, X2)),
                      zWadr(ok(X1), ok(X2)) -> ok(zWadr(X1, X2)),
                            prefix(mark(X)) -> mark(prefix(X)),
                              prefix(ok(X)) -> ok(prefix(X)),
                        proper(app(X1, X2)) -> app(proper(X1), proper(X2)),
                              proper(nil()) -> ok(nil()),
                       proper(cons(X1, X2)) -> cons(proper(X1), proper(X2)),
                            proper(from(X)) -> from(proper(X)),
                               proper(s(X)) -> s(proper(X)),
                      proper(zWadr(X1, X2)) -> zWadr(proper(X1), proper(X2)),
                          proper(prefix(X)) -> prefix(proper(X)),
                               top(mark(X)) -> top(proper(X)),
                                 top(ok(X)) -> top(active(X))
   }
  Fail