MAYBE 'Pop* (timeout of 60.0 seconds)' -------------------------------- Answer: MAYBE Input Problem: innermost runtime-complexity with respect to Rules: { is_empty(nil()) -> true() , is_empty(cons(x, l)) -> false() , hd(cons(x, l)) -> x , tl(cons(x, l)) -> l , append(l1, l2) -> ifappend(l1, l2, l1) , ifappend(l1, l2, nil()) -> l2 , ifappend(l1, l2, cons(x, l)) -> cons(x, append(l, l2))} Proof Output: The input cannot be shown compatible