0 QTRS
and(true, X) → X and(false, Y) → false if(true, X, Y) → X if(false, X, Y) → Y add(0, X) → X add(s(X), Y) → s(add(X, Y)) first(0, X) → nil first(s(X), cons(Y, Z)) → cons(Y, first(X, Z)) from(X) → cons(X, from(s(X)))