MAYBE
TRS:
 {    app(app(append(), app(app(cons(), x), xs)), ys) -> app(app(cons(), x), app(app(append(), xs), ys)),
                        app(app(append(), nil()), ys) -> ys,
              app(app(flatwith(), f), app(leaf(), x)) -> app(app(cons(), app(f, x)), nil()),
             app(app(flatwith(), f), app(node(), xs)) -> app(app(flatwithsub(), f), xs),
  app(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app(app(append(), app(app(flatwith(), f), x)), app(app(flatwithsub(), f), xs)),
                    app(app(flatwithsub(), f), nil()) -> nil()}
 DP:
  Strict:
   {    app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(app(append(), xs), ys),
        app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(app(cons(), x), app(app(append(), xs), ys)),
        app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(append(), xs),
                app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x),
                app#(app(flatwith(), f), app(leaf(), x)) -> app#(app(cons(), app(f, x)), nil()),
                app#(app(flatwith(), f), app(leaf(), x)) -> app#(cons(), app(f, x)),
               app#(app(flatwith(), f), app(node(), xs)) -> app#(app(flatwithsub(), f), xs),
               app#(app(flatwith(), f), app(node(), xs)) -> app#(flatwithsub(), f),
    app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(append(), app(app(flatwith(), f), x)), app(app(flatwithsub(), f), xs)),
    app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwith(), f), x),
    app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs),
    app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(append(), app(app(flatwith(), f), x)),
    app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(flatwith(), f)}
  Weak:
  {    app(app(append(), app(app(cons(), x), xs)), ys) -> app(app(cons(), x), app(app(append(), xs), ys)),
                         app(app(append(), nil()), ys) -> ys,
               app(app(flatwith(), f), app(leaf(), x)) -> app(app(cons(), app(f, x)), nil()),
              app(app(flatwith(), f), app(node(), xs)) -> app(app(flatwithsub(), f), xs),
   app(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app(app(append(), app(app(flatwith(), f), x)), app(app(flatwithsub(), f), xs)),
                     app(app(flatwithsub(), f), nil()) -> nil()}
  EDG:
   {(app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(flatwith(), f))
    (app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(append(), app(app(flatwith(), f), x)))
    (app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs))
    (app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwith(), f), x))
    (app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(append(), app(app(flatwith(), f), x)), app(app(flatwithsub(), f), xs)))
    (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(flatwith(), f))
    (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(append(), app(app(flatwith(), f), x)))
    (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs))
    (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwith(), f), x))
    (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(append(), app(app(flatwith(), f), x)), app(app(flatwithsub(), f), xs)))
    (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(flatwith(), f), app(node(), xs)) -> app#(flatwithsub(), f))
    (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(flatwith(), f), app(node(), xs)) -> app#(app(flatwithsub(), f), xs))
    (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(flatwith(), f), app(leaf(), x)) -> app#(cons(), app(f, x)))
    (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(flatwith(), f), app(leaf(), x)) -> app#(app(cons(), app(f, x)), nil()))
    (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x))
    (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(append(), xs))
    (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(app(cons(), x), app(app(append(), xs), ys)))
    (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(app(append(), xs), ys))
    (app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(append(), app(app(flatwith(), f), x)), app(app(flatwithsub(), f), xs)), app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(append(), xs))
    (app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(append(), app(app(flatwith(), f), x)), app(app(flatwithsub(), f), xs)), app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(app(cons(), x), app(app(append(), xs), ys)))
    (app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(append(), app(app(flatwith(), f), x)), app(app(flatwithsub(), f), xs)), app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(app(append(), xs), ys))
    (app#(app(flatwith(), f), app(node(), xs)) -> app#(app(flatwithsub(), f), xs), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(append(), app(app(flatwith(), f), x)), app(app(flatwithsub(), f), xs)))
    (app#(app(flatwith(), f), app(node(), xs)) -> app#(app(flatwithsub(), f), xs), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwith(), f), x))
    (app#(app(flatwith(), f), app(node(), xs)) -> app#(app(flatwithsub(), f), xs), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs))
    (app#(app(flatwith(), f), app(node(), xs)) -> app#(app(flatwithsub(), f), xs), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(append(), app(app(flatwith(), f), x)))
    (app#(app(flatwith(), f), app(node(), xs)) -> app#(app(flatwithsub(), f), xs), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(flatwith(), f))
    (app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwith(), f), x), app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x))
    (app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwith(), f), x), app#(app(flatwith(), f), app(leaf(), x)) -> app#(app(cons(), app(f, x)), nil()))
    (app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwith(), f), x), app#(app(flatwith(), f), app(leaf(), x)) -> app#(cons(), app(f, x)))
    (app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwith(), f), x), app#(app(flatwith(), f), app(node(), xs)) -> app#(app(flatwithsub(), f), xs))
    (app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwith(), f), x), app#(app(flatwith(), f), app(node(), xs)) -> app#(flatwithsub(), f))
    (app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(app(append(), xs), ys), app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(app(append(), xs), ys))
    (app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(app(append(), xs), ys), app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(app(cons(), x), app(app(append(), xs), ys)))
    (app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(app(append(), xs), ys), app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(append(), xs))}
   SCCS:
    Scc:
     {            app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x),
                 app#(app(flatwith(), f), app(node(), xs)) -> app#(app(flatwithsub(), f), xs),
      app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwith(), f), x),
      app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs)}
    Scc:
     {app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(app(append(), xs), ys)}
    SCC:
     Strict:
      {            app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x),
                  app#(app(flatwith(), f), app(node(), xs)) -> app#(app(flatwithsub(), f), xs),
       app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwith(), f), x),
       app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs)}
     Weak:
     {    app(app(append(), app(app(cons(), x), xs)), ys) -> app(app(cons(), x), app(app(append(), xs), ys)),
                            app(app(append(), nil()), ys) -> ys,
                  app(app(flatwith(), f), app(leaf(), x)) -> app(app(cons(), app(f, x)), nil()),
                 app(app(flatwith(), f), app(node(), xs)) -> app(app(flatwithsub(), f), xs),
      app(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app(app(append(), app(app(flatwith(), f), x)), app(app(flatwithsub(), f), xs)),
                        app(app(flatwithsub(), f), nil()) -> nil()}
     SPSC:
      Simple Projection:
       pi(app#) = 1
      Strict:
       {            app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x),
                   app#(app(flatwith(), f), app(node(), xs)) -> app#(app(flatwithsub(), f), xs),
        app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs)}
      EDG:
       {(app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs))
        (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x))
        (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(flatwith(), f), app(node(), xs)) -> app#(app(flatwithsub(), f), xs))
        (app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs))
        (app#(app(flatwith(), f), app(node(), xs)) -> app#(app(flatwithsub(), f), xs), app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs))}
       SCCS:
        Scc:
         {app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs)}
        Scc:
         {app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x)}
        SCC:
         Strict:
          {app#(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app#(app(flatwithsub(), f), xs)}
         Weak:
         {    app(app(append(), app(app(cons(), x), xs)), ys) -> app(app(cons(), x), app(app(append(), xs), ys)),
                                app(app(append(), nil()), ys) -> ys,
                      app(app(flatwith(), f), app(leaf(), x)) -> app(app(cons(), app(f, x)), nil()),
                     app(app(flatwith(), f), app(node(), xs)) -> app(app(flatwithsub(), f), xs),
          app(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app(app(append(), app(app(flatwith(), f), x)), app(app(flatwithsub(), f), xs)),
                            app(app(flatwithsub(), f), nil()) -> nil()}
         SPSC:
          Simple Projection:
           pi(app#) = 1
          Strict:
           {}
          Qed
        SCC:
         Strict:
          {app#(app(flatwith(), f), app(leaf(), x)) -> app#(f, x)}
         Weak:
         {    app(app(append(), app(app(cons(), x), xs)), ys) -> app(app(cons(), x), app(app(append(), xs), ys)),
                                app(app(append(), nil()), ys) -> ys,
                      app(app(flatwith(), f), app(leaf(), x)) -> app(app(cons(), app(f, x)), nil()),
                     app(app(flatwith(), f), app(node(), xs)) -> app(app(flatwithsub(), f), xs),
          app(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app(app(append(), app(app(flatwith(), f), x)), app(app(flatwithsub(), f), xs)),
                            app(app(flatwithsub(), f), nil()) -> nil()}
         SPSC:
          Simple Projection:
           pi(app#) = 0
          Strict:
           {}
          Qed
    SCC:
     Strict:
      {app#(app(append(), app(app(cons(), x), xs)), ys) -> app#(app(append(), xs), ys)}
     Weak:
     {    app(app(append(), app(app(cons(), x), xs)), ys) -> app(app(cons(), x), app(app(append(), xs), ys)),
                            app(app(append(), nil()), ys) -> ys,
                  app(app(flatwith(), f), app(leaf(), x)) -> app(app(cons(), app(f, x)), nil()),
                 app(app(flatwith(), f), app(node(), xs)) -> app(app(flatwithsub(), f), xs),
      app(app(flatwithsub(), f), app(app(cons(), x), xs)) -> app(app(append(), app(app(flatwith(), f), x)), app(app(flatwithsub(), f), xs)),
                        app(app(flatwithsub(), f), nil()) -> nil()}
     Fail