notPrime

#include <iostream>
#include <cmath>
#include <fstream>

using namespace std;

const char DF[] = "duom.txt";
const char AF[] = "ats.txt";

void read(ifstream &df);
void doit();
void release(ofstream &af);

int n;
int notPrimes = 0;
int X[50];

int main()
{
    n=0;
    ifstream df(DF);
    read(df);
    doit();
    ofstream af(AF);
    release(af);
    return 0;
}

void read(ifstream &df)
{
    df >> n;
    for (int i = 0; i < n; i++)
        df >> X[i];
}

void doit()
{
    for (int i = 0; i < n; i++)
    {
        for (int p = 2; p*p <= X[i]; p++)
        {
            if (X[i] % p == 0)
            {
                cerr << X[i] << endl;
                X[notPrimes] = X[i];
                notPrimes++;
                p = X[i]; // cia kad breiko nereiketu
            }
        }
    }
}

void release(ofstream &af)
{
    for (int i = 0; i < notPrimes; i++)
        af << X[i] << endl;
}