Problem #7

#include <iostream>
#include <ctime>
#include <cmath>

using namespace std;

bool isPrime (int);

int main()
{
    clock_t start = clock();
    int total = 0;
    int count = 0;
    int count2 = 0;

    while (true)
    {
        if (isPrime (count))
            count2++;

        if (count2 == 10001)
        {
            total = count;
            break;
        }
        else
            count++;
    }

    cout << total << endl 
         << "Process took " << (static_cast<double> (clock()) - start) / CLOCKS_PER_SEC << " seconds." << endl;

    system ("pause");
    return 0;
}

bool isPrime (int num)    
{    
    if (num == 0 || num == 1)  
        return false;  
  
    if (num == 2 || num == 3)    
        return true;    
    
    for (unsigned int i = 2; i < static_cast<int> (sqrt (static_cast<double> (num))) + 1; i++)    
        if (num % i == 0)    
            return false;    
   return true;    
}