box naive_icp::solve(box b, contractor const & ctc, SMTConfig & config) {
vector<box> solns;
vector<box> box_stack;
box_stack.push_back(b);
do {
DREAL_LOG_INFO << "icp_loop()"
<< "\t" << "box stack Size = " << box_stack.size();
b = box_stack.back();
box_stack.pop_back();
try {
b = ctc.prune(b, config);
if (config.nra_use_stat) { config.nra_stat.increase_prune(); }
} catch (contractor_exception & e) {
// Do nothing
}
if (!b.is_empty()) {
tuple<int, box, box> splits = b.bisect(config.nra_precision);
if (config.nra_use_stat) { config.nra_stat.increase_branch(); }
int const i = get<0>(splits);
if (i >= 0) {
box const & first = get<1>(splits);
box const & second = get<2>(splits);
if (second.is_bisectable()) {
box_stack.push_back(second);
box_stack.push_back(first);
} else {
box_stack.push_back(first);
box_stack.push_back(second);
}
if (config.nra_proof) {
config.nra_proof_out << "[branched on "
<< b.get_name(i)
<< "]" << endl;
}
} else {
config.nra_found_soln++;
if (config.nra_found_soln >= config.nra_multiple_soln) {
break;
}
if (config.nra_multiple_soln > 1) {
// If --multiple_soln is used
output_solution(b, config, config.nra_found_soln);
}
solns.push_back(b);
}
}
} while (box_stack.size() > 0);
if (config.nra_multiple_soln > 1 && solns.size() > 0) {
return solns.back();
} else {
assert(!b.is_empty() || box_stack.size() == 0);
// cerr << "BEFORE ADJUST_BOUND\n==================\n" << b << "=========================\n\n\n";
b.adjust_bound(box_stack);
// cerr << "AFTER ADJUST_BOUND\n==================\n" << b << "=========================\n\n\n";
return b;
}
}
box ncbt_icp::solve(box b, contractor const & ctc, SMTConfig & config) {
static unsigned prune_count = 0;
vector<box> box_stack;
vector<int> bisect_var_stack;
box_stack.push_back(b);
bisect_var_stack.push_back(-1); // Dummy var
do {
// Loop Invariant
assert(box_stack.size() == bisect_var_stack.size());
DREAL_LOG_INFO << "new_icp_loop()"
<< "\t" << "box stack Size = " << box_stack.size();
b = box_stack.back();
try {
b = ctc.prune(b, config);
if (config.nra_use_stat) { config.nra_stat.increase_prune(); }
} catch (contractor_exception & e) {
// Do nothing
}
prune_count++;
box_stack.pop_back();
bisect_var_stack.pop_back();
if (!b.is_empty()) {
// SAT
tuple<int, box, box> splits = b.bisect(config.nra_precision);
if (config.nra_use_stat) { config.nra_stat.increase_branch(); }
int const index = get<0>(splits);
if (index >= 0) {
box const & first = get<1>(splits);
box const & second = get<2>(splits);
if (second.is_bisectable()) {
box_stack.push_back(second);
box_stack.push_back(first);
} else {
box_stack.push_back(first);
box_stack.push_back(second);
}
bisect_var_stack.push_back(index);
bisect_var_stack.push_back(index);
} else {
break;
}
} else {
// UNSAT
while (box_stack.size() > 0) {
assert(box_stack.size() == bisect_var_stack.size());
int bisect_var = bisect_var_stack.back();
ibex::BitSet const & input = ctc.input();
DREAL_LOG_DEBUG << ctc;
if (!input[bisect_var]) {
box_stack.pop_back();
bisect_var_stack.pop_back();
} else {
break;
}
}
}
} while (box_stack.size() > 0);
DREAL_LOG_DEBUG << "prune count = " << prune_count;
b.adjust_bound(box_stack);
return b;
}