#include <vector>
#include <cmath>
using std::vector;
vector<int> list;
bool isPrime(int nNum);

int main() {
	int thisNumber;
	for(int i = 2; list.size() < 1000000; ++i) {
		thisNumber = i;
		if(isPrime(thisNumber)) {
			list.push_back(thisNumber);
		}
	}
}

bool isPrime(int nNum) {
	int maxFactor = int(sqrt(nNum)), thisFactor;
	bool bRetVal = true;
	for(int i = 0; i < list.size(); ++i) {
		thisFactor = list[i];
		if(thisFactor > maxFactor) {
			break;
		}
		if(nNum % thisFactor == 0) {
			bRetVal = false;
			break;
		}
	}
	return bRetVal;
}