public PrimeFactors(long number)
{
var primes = new PrimeGenerator();
long remainingToFactor = number;
long largestPrime = number; // if we don't find one it's a prime.
primes.CurrentNumber = 1;
while (primes.CurrentNumber <= remainingToFactor)
{
primes.GetNext();
// Pull off as many factors as we can with this prime
while (remainingToFactor % primes.CurrentNumber == 0)
{
MyFactors.Add(primes.CurrentNumber);
remainingToFactor = remainingToFactor / primes.CurrentNumber;
}
}
if (MyFactors.Count == 0)
{ // it's prime;
MyFactors.Add(1);
MyFactors.Add(number);
}
}
public long GetNthPrime(int n)
{
var generator = new PrimeGenerator();
for (int i = 0; i < n; i++)
generator.GetNext();
return generator.CurrentNumber;
}
public long GetSumOfPrimes(int maxPrime)
{
long result = 0;
var generator = new PrimeGenerator();
while (generator.GetNext() < maxPrime)
{
result += generator.CurrentNumber;
}
return result;
}
public void GetNextTest()
{
long[] primes = { 2, 3, 5, 7, 11, 13, 17 };
var generator = new PrimeGenerator();
foreach (long prime in primes)
{
Assert.AreEqual(prime, generator.GetNext());
}
}