public static MultivariatePolynomial GCD(MultivariatePolynomial left, MultivariatePolynomial right)
{
MultivariatePolynomial dividend = left.Clone();
MultivariatePolynomial divisor = right.Clone();
MultivariatePolynomial quotient;
MultivariatePolynomial remainder;
BigInteger dividendLeadingCoefficient = 0;
BigInteger divisorLeadingCoefficient = 0;
bool swap = false;
do
{
swap = false;
dividendLeadingCoefficient = dividend.Terms.Last().CoEfficient;
divisorLeadingCoefficient = divisor.Terms.Last().CoEfficient;
if (dividend.Degree < divisor.Degree)
{
swap = true;
}
else if (dividend.Degree == divisor.Degree && dividendLeadingCoefficient < divisorLeadingCoefficient)
{
swap = true;
}
if (swap)
{
MultivariatePolynomial temp = dividend.Clone();
dividend = divisor;
divisor = temp.Clone();
}
quotient = MultivariatePolynomial.Divide(dividend, divisor);
dividend = quotient.Clone();
}while (BigInteger.Abs(dividendLeadingCoefficient) > 0 && BigInteger.Abs(divisorLeadingCoefficient) > 0 && dividend.HasVariables() && divisor.HasVariables());
if (dividend.HasVariables())
{
return(divisor.Clone());
}
else
{
return(dividend.Clone());
}
}
