Solving ../../benchmarks/smtlib/true/append_not_null_cons_elt.smt2... Inference procedure has parameters: Ice fuel: 200 Timeout: Some(60.) (sec) Teacher_type: Checks all clauses every time Approximation method: remove every clause that can be safely removed Learning problem is: env: { elt -> {a, b} ; eltlist -> {cons, nil} } definition: { (append, F: { append(nil, l2, l2) <= True append(cons(h1, t1), l2, cons(h1, _ae)) <= append(t1, l2, _ae) } eq_eltlist(_de, _ee) <= append(_be, _ce, _de) /\ append(_be, _ce, _ee) ) (not_null, P: { not_null(cons(x, ll)) <= True False <= not_null(nil) } ) } properties: { not_null(_fe) <= append(cons(i, l1), l2, _fe) } over-approximation: {append} under-approximation: {not_null} Clause system for inference is: { append(nil, l2, l2) <= True -> 0 append(cons(h1, t1), l2, cons(h1, _ae)) <= append(t1, l2, _ae) -> 0 not_null(_fe) <= append(cons(i, l1), l2, _fe) -> 0 False <= not_null(nil) -> 0 } Solving took 0.031802 seconds. Yes: |_ name: None append -> [ append : { append(cons(x_0_0, x_0_1), cons(x_1_0, x_1_1), cons(x_2_0, x_2_1)) <= True append(cons(x_0_0, x_0_1), nil, cons(x_2_0, x_2_1)) <= True append(nil, cons(x_1_0, x_1_1), cons(x_2_0, x_2_1)) <= True append(nil, nil, nil) <= True } ] ; not_null -> [ not_null : { not_null(cons(x_0_0, x_0_1)) <= True } ] -- Equality automata are defined for: {elt, eltlist} _| ------------------- STEPS: ------------------------------------------- Step 0, which took 0.006098 s (model generation: 0.006059, model checking: 0.000039): Clauses: { append(nil, l2, l2) <= True -> 0 append(cons(h1, t1), l2, cons(h1, _ae)) <= append(t1, l2, _ae) -> 0 not_null(_fe) <= append(cons(i, l1), l2, _fe) -> 0 False <= not_null(nil) -> 0 } Accumulated learning constraints: { } Current best model: |_ name: None append -> [ append : { } ] ; not_null -> [ not_null : { } ] -- Equality automata are defined for: {elt, eltlist} _| Answer of teacher: append(nil, l2, l2) <= True : Yes: { l2 -> nil } append(cons(h1, t1), l2, cons(h1, _ae)) <= append(t1, l2, _ae) : No: () not_null(_fe) <= append(cons(i, l1), l2, _fe) : No: () False <= not_null(nil) : No: () ------------------------------------------- Step 1, which took 0.005883 s (model generation: 0.005844, model checking: 0.000039): Clauses: { append(nil, l2, l2) <= True -> 0 append(cons(h1, t1), l2, cons(h1, _ae)) <= append(t1, l2, _ae) -> 0 not_null(_fe) <= append(cons(i, l1), l2, _fe) -> 0 False <= not_null(nil) -> 0 } Accumulated learning constraints: { append(nil, nil, nil) <= True } Current best model: |_ name: None append -> [ append : { append(nil, nil, nil) <= True } ] ; not_null -> [ not_null : { } ] -- Equality automata are defined for: {elt, eltlist} _| Answer of teacher: append(nil, l2, l2) <= True : Yes: { l2 -> cons(_jbud_0, _jbud_1) } append(cons(h1, t1), l2, cons(h1, _ae)) <= append(t1, l2, _ae) : Yes: { _ae -> nil ; l2 -> nil ; t1 -> nil } not_null(_fe) <= append(cons(i, l1), l2, _fe) : No: () False <= not_null(nil) : No: () ------------------------------------------- Step 2, which took 0.008096 s (model generation: 0.008050, model checking: 0.000046): Clauses: { append(nil, l2, l2) <= True -> 0 append(cons(h1, t1), l2, cons(h1, _ae)) <= append(t1, l2, _ae) -> 0 not_null(_fe) <= append(cons(i, l1), l2, _fe) -> 0 False <= not_null(nil) -> 0 } Accumulated learning constraints: { append(cons(a, nil), nil, cons(a, nil)) <= True append(nil, cons(a, nil), cons(a, nil)) <= True append(nil, nil, nil) <= True } Current best model: |_ name: None append -> [ append : { append(cons(x_0_0, x_0_1), nil, cons(x_2_0, x_2_1)) <= True append(nil, cons(x_1_0, x_1_1), cons(x_2_0, x_2_1)) <= True append(nil, nil, nil) <= True } ] ; not_null -> [ not_null : { } ] -- Equality automata are defined for: {elt, eltlist} _| Answer of teacher: append(nil, l2, l2) <= True : No: () append(cons(h1, t1), l2, cons(h1, _ae)) <= append(t1, l2, _ae) : Yes: { _ae -> cons(_nbud_0, _nbud_1) ; l2 -> cons(_obud_0, _obud_1) ; t1 -> nil } not_null(_fe) <= append(cons(i, l1), l2, _fe) : Yes: { _fe -> cons(_qbud_0, _qbud_1) ; l2 -> nil } False <= not_null(nil) : No: () Total time: 0.031802 Learner time: 0.019953 Teacher time: 0.000124 Reasons for stopping: Yes: |_ name: None append -> [ append : { append(cons(x_0_0, x_0_1), cons(x_1_0, x_1_1), cons(x_2_0, x_2_1)) <= True append(cons(x_0_0, x_0_1), nil, cons(x_2_0, x_2_1)) <= True append(nil, cons(x_1_0, x_1_1), cons(x_2_0, x_2_1)) <= True append(nil, nil, nil) <= True } ] ; not_null -> [ not_null : { not_null(cons(x_0_0, x_0_1)) <= True } ] -- Equality automata are defined for: {elt, eltlist} _|