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