TRS:
 {       first(0(), X) -> nil(),
  first(s(X), cons(Y)) -> cons(Y),
               from(X) -> cons(X)}
 Cdiprover:
  Interpretation class: pizerosimplemixed
  Complexity bound: POLYTIME COMPUTABLE
  from(X4) = + 0*X4^2 + 2 + 2*X4
  s(X3) = + 1*X3 + 1
  cons(X2) = + 1*X2 + 1
  0 = + 1
  first(X1, X0) = + 0*X1^2 + 0*X0^2 + 2*X1 + 0 + 2*X0 + 0*X0*X1
  nil = + 1
  
  Qed