iTextSharp.text.pdf.qrcode.GF256.AddOrSubtract C# (CSharp) Method

        internal static int AddOrSubtract(int a, int b) {
            return a ^ b;
        }

        internal GF256Poly Multiply(GF256Poly other)
        {
            if (!field.Equals(other.field))
            {
                throw new ArgumentException("GF256Polys do not have same GF256 field");
            }
            if (IsZero() || other.IsZero())
            {
                return(field.GetZero());
            }
            var aCoefficients = coefficients;
            var aLength       = aCoefficients.Length;
            var bCoefficients = other.coefficients;
            var bLength       = bCoefficients.Length;
            var product       = new int[aLength + bLength - 1];

            for (var i = 0; i < aLength; i++)
            {
                var aCoeff = aCoefficients[i];
                for (var j = 0; j < bLength; j++)
                {
                    product[i + j] = GF256.AddOrSubtract(product[i + j],
                                                         field.Multiply(aCoeff, bCoefficients[j]));
                }
            }
            return(new GF256Poly(field, product));
        }