Prime number thing

primes.cpp

#include <iostream>
#include <iomanip>
#include <cmath>
using namespace std;

bool isPrime (long long n)
{
	bool tempbool = true;

	if (n <= 3) {
		return true;
    }
    else if (n % 2 == 0) {
        return false;
    }

    int sqrtN = (int)sqrt((long double)n);
    for (int i = 3; i <= sqrtN; i++) {
        if (n % i == 0)
            return false;
    }

    // End of the world condition.
    return true;
}

int main()
{
    long i = 2;
    long double j = 0;
	long double templogs = 0;
	long double logs1 = 0;
	long double logs2 = 0;
	long double logs3 = 0;
	long double logs4 = 0;
	long double logs5 = 0;
	long double logs6 = 0;

	int n = 100;
    bool shouldExit = false;
	while (shouldExit == false)
	{
        // Start at two because less is always prime. Or negative.
		for (; i <= n; i++)
		{
			if (isPrime(i))
			{
                j = i;
				if ( n == 100 )
					cout << i << " ";
				templogs += log(j);
			}
		}
		switch (n)
		{
		case 100:		//one hundred
			n = 1000;	//one thousand
			logs1 = templogs;            
			break;
		case 1000:		//one thousand
			n = 10000;	//ten thousand
			logs2 = templogs;            
			break;
		case 10000:		//ten thousand
			n = 100000;	//one hundred thousand
			logs3 = templogs;
			break;
		case 100000:	//one hundred thousand
			n= 1000000;	//one million
			logs4 = templogs;
			break;
		case 1000000:	//one million
			n = 10000000; //ten million
			logs5 = templogs;
			break;
		case 10000000:	//ten million
			logs6 = templogs;
            shouldExit = true;
            break;
		}
	}
	cout << fixed << "\n\n" << setw(15) << "Sum of logs" << setw(9) << "n" << setw(9) << "Ratio" << endl;
	cout << fixed << setw(15) << logs1 << setw(9) << "100" << setw(9) << "Ratio" << endl;
	cout << fixed << setw(15) << logs2 << setw(9) << "1000" << setw(9) << "Ratio" << endl;
    cout << fixed << setw(15) << logs3 << setw(9) << "10000" << setw(9) << "Ratio" << endl;
    cout << fixed << setw(15) << logs4 << setw(9) << "100000" << setw(9) << "Ratio" << endl;
    cout << fixed << setw(15) << logs5 << setw(9) << "1000000" << setw(9) << "Ratio" << endl;
    cout << fixed << setw(15) << logs6 << setw(9) << "10000000" << setw(9) << "Ratio" << endl;
	cin.get();

	return 0;
}