MAYBE

'Pop* (timeout of 60.0 seconds)'
--------------------------------
Answer:           MAYBE
Input Problem:    innermost runtime-complexity with respect to
  Rules:
    {  a____(__(X, Y), Z) -> a____(mark(X), a____(mark(Y), mark(Z)))
     , a____(X, nil()) -> mark(X)
     , a____(nil(), X) -> mark(X)
     , a__U11(tt()) -> a__U12(tt())
     , a__U12(tt()) -> tt()
     , a__isNePal(__(I, __(P, I))) -> a__U11(tt())
     , mark(__(X1, X2)) -> a____(mark(X1), mark(X2))
     , mark(U11(X)) -> a__U11(mark(X))
     , mark(U12(X)) -> a__U12(mark(X))
     , mark(isNePal(X)) -> a__isNePal(mark(X))
     , mark(nil()) -> nil()
     , mark(tt()) -> tt()
     , a____(X1, X2) -> __(X1, X2)
     , a__U11(X) -> U11(X)
     , a__U12(X) -> U12(X)
     , a__isNePal(X) -> isNePal(X)}

Proof Output:    
  The input cannot be shown compatible