List prime numbers between an interval

primeNumbers.cpp

#include <iostream>
#include <math.h>
using namespace std;

int main(int argc, char const *argv[]) {

  // We expect 3 arguments: the program name, the initial value and final value
  if (argc != 3) {
    cerr << "Usage: " << argv[0] << " INITIAL FINAL (positive integer values)."
         << endl;
    return EXIT_FAILURE;
  }

  // We expect argument 2 to be greater then argument 1
  if (atoi(argv[2]) < atoi(argv[1])) {
    cerr << "Second argument should be greater then first!" << endl;
    return EXIT_FAILURE;
  }

  if (atoi(argv[2]) >= 2 && atoi(argv[1]) <= 2)
    cout << "2 ";

  if (atoi(argv[2]) >= 3 && atoi(argv[1]) <= 3)
    cout << "3 ";

  for (int i = atoi(argv[1]); i <= atoi(argv[2]); i++) {
    for (int n = 2; n * n <= i; n++) {
      if (i % n == 0)
        break;
      else if (n + 1 > sqrt(i)) {
        cout << i << " ";
      }
    }
  }

  cout << endl;

  return EXIT_SUCCESS;
}