// EX4_09.CPP
  // Calculating primes
  include <iostream>
  include <iomanip>
  using std::cout;
  using std::endl;
  using std::setw;
  
  int main()
  {
     const int MAX = 100;           // Number of primes required
     long primes[MAX] = { 2,3,5 };  // First three primes defined
     long trial = 5;                // Candidate prime
     int count = 3;                 // Count of primes found
     int found = 0;                 // Indicates when a prime is found
  
     do
     {
        trial += 2;                      // Next value for checking
        found = 0;                       // Set found indicator
        for(int i = 0; i < count; i++)   // Try division by existing primes
        {
           found = (trial % *(primes + i)) == 0;// True for exact division
             if(found)                          // If division is exact
                break;                          // it's not a prime
        }
        if (found == 0)                  // We got one...
           *(primes + count++) = trial;  // ...so save it in primes array
     }while(count < MAX);
  
     // Output primes 5 to a line
     for(int i = 0; i < MAX; i++)
     {
        if(i % 5 == 0)                 // New line on 1st, and every 5th line
           cout << endl;
        cout << setw(10) << *(primes + i);
     }
     cout << endl;
     return 0;
  }