#include <bits/stdc++.h>
int isPrime(int num) {
  int rtn = 1;
  int i;
  for (i = 2; i * i <= num; i++) {
    if (num % i == 0) {
      rtn = 0;
      break;
    }
  }
  return rtn;
}
int main(void) {
  int sum, num;
  int i;
  int ans = 0;
  scanf("%d", &sum);
  for (i = 0; i < sum; i++) {
    scanf("%d", &num);
    if (isPrime(num)) ans++;
  }
  printf("%d/n", ans);
  return 0;
}
