MAYBE
MAYBE
TRS:
 {
           f(ok(X)) -> ok(f(X)),
         g(mark(X)) -> mark(g(X)),
           g(ok(X)) -> ok(g(X)),
  active(f(f(a()))) -> mark(f(g(f(a())))),
       active(g(X)) -> g(active(X)),
       proper(f(X)) -> f(proper(X)),
       proper(g(X)) -> g(proper(X)),
        proper(a()) -> ok(a()),
       top(mark(X)) -> top(proper(X)),
         top(ok(X)) -> top(active(X))
 }
 DUP: We consider a non-duplicating system.
  Trs:
   {
             f(ok(X)) -> ok(f(X)),
           g(mark(X)) -> mark(g(X)),
             g(ok(X)) -> ok(g(X)),
    active(f(f(a()))) -> mark(f(g(f(a())))),
         active(g(X)) -> g(active(X)),
         proper(f(X)) -> f(proper(X)),
         proper(g(X)) -> g(proper(X)),
          proper(a()) -> ok(a()),
         top(mark(X)) -> top(proper(X)),
           top(ok(X)) -> top(active(X))
   }
  Fail