//-------------------------------------------------------
//Filename:
//Author:
//Date:
//Description:
//
//
//
//
//
//-------------------------------------------------------
#include <stdio.h>
#include <iostream>
#include <stdlib.h>
#include <sys/types.h>
#include <cmath>
using namespace std;

int SumofPrimes(int, int, int[]);
void printPrimes(int, int[]);
void populatePrimes(int, int[]);

int main (int argc, char *argv[])
{
        int pid;
        int sum = 0;
        int number = atoi(argv[1]); //saves the number they input
        int primes[number];         //declare an array "primes"

        populatePrimes(number, primes); //function call to populate the array
        pid = fork(); //function call to fork

        if (pid == 0)   //child
        {
                cout << "Child Printing..." << "The sum of the first n prime numbers is: " << SumofPrimes(sum, number, primes) << endl;;
                cout << "Child Printing... Proc ID = " << getpid() << ". Child CPU time = " << endl;

                exit(0);
        }
        else            //parent
        {
                cout << "Parent Printing... Child pid = " << pid << " Child CPU time = " << endl;
                cout << "Parent Printing... Proc ID = " << getpid() << ". Parent CPU time = " << endl;
                cout << "Parent Printing... The first " << number << " prime numbers are: ";

                printPrimes(number, primes);   //this function will print the prime
                                               //numbers in the primes array
                exit(0);
        }


}
//************************************************
//This function is used to populate the array primes.
//
//The program will:
//      1)Determine if the number is a 0 or 1
//              (Neither are primes)
//      2)If number is >= 2, the program will store
//        2 as the first prime, and will from there
//        calculate the rest of the primes, and store
//        them in the array primes.
//************************************************
void populatePrimes(int number, int primes[])
{
        int k = 0;
        if(number == 1 || number == 0) // one isn't prime and also one isn't compound
        {
                cout << "there aren't any prime number" << endl;
                return;
        }

        primes[k] = 2; //the first prime is 2, k then becomes 1
        k++;

        for(int n = 3; k < number; n++)
        {
                bool prime = true;

                for(int i = 0; k/primes[i]; i++)
                {
                        if(n % primes[i] == 0)
                        {
                                prime = false;
                                break;
                        }
                }
                if(prime)
                {
                        primes[k++] = n;
                }
        }
        return;

}

//************************************************
//This function is used to calculate the sum of the
//prime numbers. It uses a for loop and loops through
//all of the values, adding them to a single variable.
//************************************************
int SumofPrimes(int sum, int number, int primes[])
{

        for(int k = 0; k < number; k++)
        {
                sum = sum + primes[k];
        }

        return sum;
}

//************************************************
//This function is used to print the prime numbers
//in the primes array. It uses a for loop and loops
//through all the values, printing each one.
//************************************************
void printPrimes(int number, int primes[])
{
        for(int k = 0; k < number; k++)
        {
                cout << primes[k] << " ";
        }

        cout << endl;
}