Solving ../../benchmarks/smtlib/false/append_equal.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: {
nat -> {s, z}  ;  natlist -> {cons, nil}
}
definition:
{
(append, F:
{
append(nil, l2, l2) <= True
append(cons(h1, t1), l2, cons(h1, _okb)) <= append(t1, l2, _okb)
}
eq_natlist(_rkb, _skb) <= append(_pkb, _qkb, _rkb) /\ append(_pkb, _qkb, _skb)
)
}

properties:
{
eq_natlist(l1, _tkb) <= append(l1, cons(i, nil), _tkb)
}


over-approximation: {append}
under-approximation: {}

Clause system for inference is:

{
append(nil, l2, l2) <= True -> 0
eq_natlist(l1, _tkb) <= append(l1, cons(i, nil), _tkb) -> 0
append(cons(h1, t1), l2, cons(h1, _okb)) <= append(t1, l2, _okb) -> 0
}


Solving took 0.039598 seconds.
No: Contradictory set of ground constraints:
{
append(cons(z, nil), nil, cons(z, nil)) <= True
append(nil, cons(z, nil), cons(z, nil)) <= True
append(nil, nil, nil) <= True
False <= append(nil, cons(z, nil), cons(z, nil))
}
-------------------
STEPS:
-------------------------------------------
Step 0, which took 0.005881 s (model generation: 0.005838,  model checking: 0.000043):

Clauses:
{
append(nil, l2, l2) <= True -> 0
eq_natlist(l1, _tkb) <= append(l1, cons(i, nil), _tkb) -> 0
append(cons(h1, t1), l2, cons(h1, _okb)) <= append(t1, l2, _okb) -> 0
}

Accumulated learning constraints:
{

}

Current best model:
|_
name: None

append ->
[
append : <natlist * natlist * natlist>
{
  
}
]



--
Equality automata are defined for: {nat, natlist}
_|




Answer of teacher:

append(nil, l2, l2) <= True  :
Yes: {
l2 -> nil
}

eq_natlist(l1, _tkb) <= append(l1, cons(i, nil), _tkb)  :
No: ()

append(cons(h1, t1), l2, cons(h1, _okb)) <= append(t1, l2, _okb)  :
No: ()


-------------------------------------------
Step 1, which took 0.006536 s (model generation: 0.006451,  model checking: 0.000085):

Clauses:
{
append(nil, l2, l2) <= True -> 0
eq_natlist(l1, _tkb) <= append(l1, cons(i, nil), _tkb) -> 0
append(cons(h1, t1), l2, cons(h1, _okb)) <= append(t1, l2, _okb) -> 0
}

Accumulated learning constraints:
{
append(nil, nil, nil) <= True
}

Current best model:
|_
name: None

append ->
[
append : <natlist * natlist * natlist>
{
  append(nil, nil, nil) <= True
}
]



--
Equality automata are defined for: {nat, natlist}
_|




Answer of teacher:

append(nil, l2, l2) <= True  :
Yes: {
l2 -> cons(_troqw_0, _troqw_1)
}

eq_natlist(l1, _tkb) <= append(l1, cons(i, nil), _tkb)  :
No: ()

append(cons(h1, t1), l2, cons(h1, _okb)) <= append(t1, l2, _okb)  :
Yes: {
_okb -> nil  ;  l2 -> nil  ;  t1 -> nil
}


-------------------------------------------
Step 2, which took 0.008786 s (model generation: 0.008729,  model checking: 0.000057):

Clauses:
{
append(nil, l2, l2) <= True -> 0
eq_natlist(l1, _tkb) <= append(l1, cons(i, nil), _tkb) -> 0
append(cons(h1, t1), l2, cons(h1, _okb)) <= append(t1, l2, _okb) -> 0
}

Accumulated learning constraints:
{
append(cons(z, nil), nil, cons(z, nil)) <= True
append(nil, cons(z, nil), cons(z, nil)) <= True
append(nil, nil, nil) <= True
}

Current best model:
|_
name: None

append ->
[
append : <natlist * natlist * natlist>
{
  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
}
]



--
Equality automata are defined for: {nat, natlist}
_|




Answer of teacher:

append(nil, l2, l2) <= True  :
No: ()

eq_natlist(l1, _tkb) <= append(l1, cons(i, nil), _tkb)  :
Yes: {
_tkb -> cons(_xroqw_0, _xroqw_1)  ;  l1 -> nil
}

append(cons(h1, t1), l2, cons(h1, _okb)) <= append(t1, l2, _okb)  :
Yes: {
_okb -> cons(_zroqw_0, _zroqw_1)  ;  l2 -> cons(_asoqw_0, _asoqw_1)  ;  t1 -> nil
}


Total time: 0.039598
Learner time: 0.021018
Teacher time: 0.000185
Reasons for stopping: No: Contradictory set of ground constraints:
{
append(cons(z, nil), nil, cons(z, nil)) <= True
append(nil, cons(z, nil), cons(z, nil)) <= True
append(nil, nil, nil) <= True
False <= append(nil, cons(z, nil), cons(z, nil))
}