public static void uint64()
{
Random64 rng = new Random64(13255);
for (int i = 0; i < 64; i++)
{
ulong x = rng.NextULong();
ulong y = rng.NextULong();
Assert.AreEqual(_gcd(x, y), maxmath.gcd(x, y));
Assert.AreEqual(0, x % _gcd(x, y));
Assert.AreEqual(0, y % _gcd(x, y));
}
}