public void BigIntegerFactorial()
{
Assert.AreEqual(BigInteger.One, GeneralMath.FactorialBigInteger(0));
var r = new Random();
for (int i = 0; i < 16; i++)
{
Assert.Throws <ArgumentException>(() => GeneralMath.FactorialBigInteger(-r.Next()));
}
BigInteger currentResult = 1;
for (int multiplier = 1; multiplier <= 100; multiplier++)
{
currentResult *= multiplier;
Assert.AreEqual(currentResult, GeneralMath.FactorialBigInteger(multiplier));
}
}