private static BigInteger CalcD(BigInteger m) =>
//var d = m - 1;
//var sqrt = m.Sqrt();
//for (int i = 2; i <= sqrt; ++i)
//{
// if ((m % i == 0) && (d % i == 0))
// {
// d--;
// i = 2;
// }
//}
BigIntegerExtension.GetRandomPrime(m.GetByteCount(), (b) => b.SolovayStrassenTest(1000));
public ElGamalsEDS(int bytesCount)
{
P = BigIntegerExtension.GetRandomPrime(bytesCount, b => b.SolovayStrassenTest(1000));
G = BigIntegerExtension.GetGroupGenerator(P);
}