prime numbers

// prime numbers 

/* This is a new method to calculate the prime numbers. Get odd numbers set,

   then subtract from it the set formed from multiplying odd numbers with each other.*/   

#include <iostream>

#include <fstream>

using namespace std;

int main()

{   int a, b, c, i; 

    int array[1000];

    i = 0;

    ofstream source;

    source.open("Prime Numbers.txt"); 

    source << "This is a list of all odd numbers where nonprimes numbers are hidden and replaced by -1." << endl; 

    source << "This gives us and leave us with the Prime Numbers shown below." << endl;

    source << endl << 2 << endl << 5 << endl;

    

    for (c=1; c<2000; c+=2)

        if (c%5==0)

            {array[i] = 0;i++;}

        else

            {array[i] = c;i++;}

            

    for (a=3; a<1000; a+=2)

        for (b=a; b<1000; b+=2)

            for (i=0; i<1000; i++)

                if ( a*b == array[i])

                     array[i] = -1;

    

    for (i=0; i<1000; i++)

        if (i%5==0)

            source << endl << "........\n" << array[i] << endl;   

        else

            source << array[i] << endl;                                   

        

    system("PAUSE");

    return 0;

    }