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fix infeasible LNS, was a bug in cumulative presolve

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This commit is contained in:
Laurent Perron
2022-11-14 20:35:24 +01:00
parent 1abb177b3a
commit d7db07736f
1 changed files with 14 additions and 9 deletions
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23
ortools/sat/cp_model_presolve.cc
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@@ -4860,7 +4860,7 @@ bool CpModelPresolver::PresolveCumulative(ConstraintProto* ct) {
int new_size = 0;
int num_zero_demand_removed = 0;
int num_zero_size_removed = 0;
int num_incompatible_demands = 0;
int num_incompatible_intervals = 0;
for (int i = 0; i < proto->intervals_size(); ++i) {
if (context_->ConstraintIsInactive(proto->intervals(i))) continue;
@@ -4871,22 +4871,27 @@ bool CpModelPresolver::PresolveCumulative(ConstraintProto* ct) {
continue;
}
if (context_->SizeMax(proto->intervals(i)) == 0) {
const int interval_index = proto->intervals(i);
if (context_->SizeMax(interval_index) == 0) {
// Size 0 intervals cannot contribute to a cumulative.
num_zero_size_removed++;
continue;
}
if (context_->MinOf(demand_expr) > capacity_max) {
if (context_->ConstraintIsOptional(proto->intervals(i))) {
const int64_t start_min = context_->StartMin(interval_index);
const int64_t end_max = context_->EndMax(interval_index);
if (start_min > end_max ||
(context_->SizeMin(interval_index) > 0 &&
context_->MinOf(demand_expr) > capacity_max)) {
if (context_->ConstraintIsOptional(interval_index)) {
ConstraintProto* interval_ct =
context_->working_model->mutable_constraints(proto->intervals(i));
context_->working_model->mutable_constraints(interval_index);
DCHECK_EQ(interval_ct->enforcement_literal_size(), 1);
const int literal = interval_ct->enforcement_literal(0);
if (!context_->SetLiteralToFalse(literal)) {
return true;
}
num_incompatible_demands++;
num_incompatible_intervals++;
continue;
} else { // Interval is performed.
return context_->NotifyThatModelIsUnsat(
@@ -4894,7 +4899,7 @@ bool CpModelPresolver::PresolveCumulative(ConstraintProto* ct) {
}
}
proto->set_intervals(new_size, proto->intervals(i));
proto->set_intervals(new_size, interval_index);
*proto->mutable_demands(new_size) = proto->demands(i);
new_size++;
}
@@ -4915,9 +4920,9 @@ bool CpModelPresolver::PresolveCumulative(ConstraintProto* ct) {
context_->UpdateRuleStats(
"cumulative: removed intervals with a size of zero");
}
if (num_incompatible_demands > 0) {
if (num_incompatible_intervals > 0) {
context_->UpdateRuleStats(
"cumulative: removed intervals demands greater than the capacity");
"cumulative: removed intervals that can't be performed");
}
}