0 QTRS
from(X) → cons(X, n__from(n__s(X))) sel(0, cons(X, Y)) → X sel(s(X), cons(Y, Z)) → sel(X, activate(Z)) from(X) → n__from(X) s(X) → n__s(X) activate(n__from(X)) → from(activate(X)) activate(n__s(X)) → s(activate(X)) activate(X) → X