YES(?,O(n^1))
TRS:
 {app(app(app(compose(), f), g), x) -> app(f, app(g, x))}
 DUP: We consider a non-duplicating system.
  Trs:
   {app(app(app(compose(), f), g), x) -> app(f, app(g, x))}
  Natural interpretation:
   Strict:
    {app(app(app(compose(), f), g), x) -> app(f, app(g, x))}
   Weak:
    {}
   Interpretation class: stronglylinear
   [compose] = + 0
   [app](X1, X0) = + 1*X0 + 1*X1 + 2
   
   Qed