public void TestDivideAndRemainder()
{
// TODO More basic tests
IBigInteger n = new BigInteger(48, _random);
IBigInteger[] qr = n.DivideAndRemainder(one);
Assert.AreEqual(n, qr[0]);
Assert.AreEqual(zero, qr[1]);
for (int rep = 0; rep < 10; ++rep)
{
IBigInteger a = new BigInteger(100 - rep, 0, _random);
IBigInteger b = new BigInteger(100 + rep, 0, _random);
IBigInteger c = new BigInteger(10 + rep, 0, _random);
IBigInteger d = a.Multiply(b).Add(c);
IBigInteger[] es = d.DivideAndRemainder(a);
Assert.AreEqual(b, es[0]);
Assert.AreEqual(c, es[1]);
}
// Special tests for power of two since uses different code path internally
for (int i = 0; i < 100; ++i)
{
int shift = _random.Next(64);
IBigInteger a = one.ShiftLeft(shift);
IBigInteger b = new BigInteger(64 + _random.Next(64), _random);
IBigInteger bShift = b.ShiftRight(shift);
IBigInteger bMod = b.And(a.Subtract(one));
string data = "shift=" + shift + ", b=" + b.ToString(16);
qr = b.DivideAndRemainder(a);
Assert.AreEqual(bShift, qr[0], data);
Assert.AreEqual(bMod, qr[1], data);
qr = b.DivideAndRemainder(a.Negate());
Assert.AreEqual(bShift.Negate(), qr[0], data);
Assert.AreEqual(bMod, qr[1], data);
qr = b.Negate().DivideAndRemainder(a);
Assert.AreEqual(bShift.Negate(), qr[0], data);
Assert.AreEqual(bMod.Negate(), qr[1], data);
qr = b.Negate().DivideAndRemainder(a.Negate());
Assert.AreEqual(bShift, qr[0], data);
Assert.AreEqual(bMod.Negate(), qr[1], data);
}
}