bool LinearPropagator::propagate_true(const LinearConstraint& l)
{
assert(l.getRelation()==LinearConstraint::Relation::LE);
auto minmax = computeMinMax(l);
if (minmax.second <= l.getRhs())
return true;
for (auto i : l.getViews())
{
auto r = vs_.getCurrentRestrictor(i);
auto wholeRange = vs_.getRestrictor(i);
std::pair<int64,int64> mm;
mm.first = minmax.first - r.lower();
mm.second = minmax.second - r.upper();
int64 up = l.getRhs() - mm.first;
if (up < r.lower())
{
//std::cout << "Constrain Variable " << i.first << " with new upper bound " << up << std::endl;
return false;
}
if (up < r.upper())
{
//std::cout << "Constrain Variable " << i.first << " with new upper bound " << up << std::endl;
//auto newUpper = std::lower_bound(wholeRange.begin(), wholeRange.end(), up);
auto newUpper = std::upper_bound(wholeRange.begin(), wholeRange.end(), up);
if (!constrainUpperBound(newUpper)) // +1 is needed, as it is in iterator pointing after the element
return false;
minmax.first = mm.first + r.lower();
minmax.second = mm.second + *(newUpper-1);
}
}
return true;
}
std::pair<int64,int64> LinearPropagator::computeMinMax(const LinearConstraint& l)
{
auto views = l.getViews();
std::pair<int64,int64> minmax(0,0);
for (auto i : views)
{
auto r = vs_.getCurrentRestrictor(i);
minmax.first += r.lower();
minmax.second += r.upper();
}
return minmax;
}
int64 LinearLiteralPropagator::computeMin(const LinearConstraint& l, itervec& clause)
{
auto& views = l.getViews();
int64 min(0);
for (auto& i : views)
{
auto r = vs_.getVariableStorage().getCurrentRestrictor(i);
assert(!r.isEmpty());
min += r.lower();
clause.emplace_back(r.begin());
}
return min;
}
std::pair<int64,int64> LinearLiteralPropagator::computeMinMax(const LinearConstraint& l, LinearConstraintClause::itervec& clause)
{
auto views = l.getViews();
std::pair<int64,int64> minmax(0,0);
for (auto i : views)
{
auto r = vs_.getVariableStorage().getCurrentRestrictor(i);
assert(!r.isEmpty());
minmax.first += r.lower();
minmax.second += r.upper();
clause.emplace_back(r.begin());
}
return minmax;
}
