/// <returns> evaluation of this polynomial at a given point
/// </returns>
internal int evaluateAt(int a)
{
if (a == 0)
{
// Just return the x^0 coefficient
return(getCoefficient(0));
}
int size = coefficients.Length;
if (a == 1)
{
// Just the sum of the coefficients
int result = 0;
for (int i = 0; i < size; i++)
{
result = GF256.addOrSubtract(result, coefficients[i]);
}
return(result);
}
int result2 = coefficients[0];
for (int i = 1; i < size; i++)
{
result2 = GF256.addOrSubtract(field.multiply(a, result2), coefficients[i]);
}
return(result2);
}
