private long GetModularMultiplicativeInverse(long exponent, long modulus)
{
var res = GCD.EuclidExtended(exponent, modulus);
if (res.D != 1)
throw new InvalidOperationException("The greatest common divisor is not 1");
return (res.X % modulus + modulus) % modulus;
}
public void EuclidExtendedTest()
{
const int a = 816;
const int b = 2260;
var result = GCD.EuclidExtended(a, b);
const long expectedResult = 4;
Assert.IsTrue(result.D == expectedResult, "Euclidean extended algorithm has incorrect result");
}