;; Same than length.smt2 but the nil case is not a rewrite rule ;; So here the rewrite rules have no guards length (set-logic AUFLIA) (set-info :status unsat) ;; don't use a datatypes for currently focusing in uf (declare-sort list 0) (declare-fun cons (Int list) list) (declare-fun nil () list) ;;define length (declare-fun length (list) Int) (assert (= (length nil) 0)) (assert (forall ((?e Int) (?l list)) (! (= (length (cons ?e ?l)) (+ 1 (length ?l))) :rewrite-rule))) (declare-fun gen_cons (Int list) list) (assert (forall ((?n Int) (?l list)) (! (=> (= ?n 0) (= (gen_cons ?n ?l) ?l)) :rewrite-rule))) (assert (forall ((?n Int) (?l list)) (! (=> (> ?n 0) (= (gen_cons ?n ?l) (gen_cons (- ?n 1) (cons 1 ?l)))) :rewrite-rule))) ;;(assert (not (forall ((?n Int)) (=> (>= ?n 0) (=> (= (length (gen_cons ?n nil)) ?n) (= (length (gen_cons (+ ?n 1) nil)) (+ ?n 1))) )))) ;;(assert (not (forall ((?n Int) (?l list)) (=> (>= ?n 0) (=> (= (length ?l) ?n) (= (length (cons 1 ?l)) (+ ?n 1))) )))) ;; (assert (not (forall ((?n Int)) (=> (>= ?n 0) (=> (= (length (gen_cons ?n nil)) ?n) (= (length (cons 1 (gen_cons ?n nil))) (+ ?n 1))) )))) ;;(assert (not (forall ((?n Int)) (=> (>= ?n 0) (= (gen_cons (+ ?n 1) nil) (cons 1 (gen_cons ?n nil))) )))) (assert (not (forall ((?n Int)) (=> (>= ?n 0) (=> (forall ((?l list)) (= (gen_cons ?n (cons 1 ?l)) (cons 1 (gen_cons ?n ?l)))) (forall ((?l list)) (= (gen_cons (+ ?n 1) (cons 1 ?l)) (cons 1 (gen_cons (+ ?n 1) ?l)))) ))))) (check-sat) (exit)