Problem #27

This one was fairly easy to reproduce:

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

using namespace std;

bool isPrime (int);
 
int main() 
{
    clock_t start = clock();
    int total = 0;
    int holder = 0;
    int count = 0;

    for (int a = -999; a < 1000; a++)
        for (int b = -999; b < 1000; b++)
        {
            count = 0;
            for (int n = 0; ; n++)
                if (isPrime (n * n + a * n + b))
                    count++;
                else
                    break;

            if (count > holder)
            {
                holder = count;
                total = a * b;
            }
        }

    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 <= 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;
}