void PseudoBooleanProcessor::learnGeqSub(Node geq)
{
Assert(geq.getKind() == kind::GEQ);
const bool negated = false;
bool success = decomposeAssertion(geq, negated);
if (!success)
{
Debug("pbs::rewrites") << "failed " << std::endl;
return;
}
Assert(d_off.value().isIntegral());
Integer off = d_off.value().ceiling();
// \sum pos >= \sum neg + off
// for now special case everything we want
// target easy clauses
if (d_pos.size() == 1 && d_neg.size() == 1 && off.isZero())
{
// x >= y
// |- (y >= 1) => (x >= 1)
Node x = d_pos.front();
Node y = d_neg.front();
Node xGeq1 = mkGeqOne(x);
Node yGeq1 = mkGeqOne(y);
Node imp = yGeq1.impNode(xGeq1);
addSub(geq, imp);
}
else if (d_pos.size() == 0 && d_neg.size() == 2 && off.isNegativeOne())
{
// 0 >= (x + y -1)
// |- 1 >= x + y
// |- (or (not (x >= 1)) (not (y >= 1)))
Node x = d_neg[0];
Node y = d_neg[1];
Node xGeq1 = mkGeqOne(x);
Node yGeq1 = mkGeqOne(y);
Node cases = (xGeq1.notNode()).orNode(yGeq1.notNode());
addSub(geq, cases);
}
else if (d_pos.size() == 2 && d_neg.size() == 1 && off.isZero())
{
// (x + y) >= z
// |- (z >= 1) => (or (x >= 1) (y >=1 ))
Node x = d_pos[0];
Node y = d_pos[1];
Node z = d_neg[0];
Node xGeq1 = mkGeqOne(x);
Node yGeq1 = mkGeqOne(y);
Node zGeq1 = mkGeqOne(z);
NodeManager* nm = NodeManager::currentNM();
Node dis = nm->mkNode(kind::OR, zGeq1.notNode(), xGeq1, yGeq1);
addSub(geq, dis);
}
}
Polynom Converter::ToPolynom(const Integer &integer)
{
Polynom result;
if(!integer.isZero())
{
uint numberDigits = integer.getNumberBytes() / result.getDigitSizeInBytes() + ((integer.getNumberBytes() % result.getDigitSizeInBytes()) != 0);
result.setNumberDigits(numberDigits);
result._digits[result._numberDigits-1] = 0;
std::memcpy(result._digits, integer._digits, integer.getNumberBytes());
}
return result;
}
Rational::Rational(const Integer numerator, const Integer denominator) {
assert(!denominator.isZero());
if (numerator.isOne() || denominator.isOne()) {
// Avoid computing GCD if possible
m_numerator = numerator;
m_denominator = denominator;
} else {
Integer gcd = Arithmetic::GCD(&numerator, &denominator);
m_numerator = Integer::Division(numerator, gcd).quotient;
m_denominator = Integer::Division(denominator, gcd).quotient;
}
if (m_numerator.isNegative() && m_denominator.isNegative()) {
m_numerator.setNegative(false);
m_denominator.setNegative(false);
} else if (m_denominator.isNegative()) {
m_numerator.setNegative(true);
m_denominator.setNegative(false);
}
}