#include <bits/stdc++.h>
using namespace std;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n;
    if (!(cin >> n)) return 0;
    vector<int> a(n);
    int maxv = 0;
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
        if (a[i] > maxv) maxv = a[i];
    }

    int limit = max(2, maxv);
    vector<char> is_prime(limit + 1, true);
    is_prime[0] = is_prime[1] = false;
    for (int p = 2; 1LL * p * p <= limit; ++p) {
        if (is_prime[p]) {
            for (int q = p * p; q <= limit; q += p) is_prime[q] = false;
        }
    }

    int cnt = 0;
    for (int x : a) if (x >= 0 && x <= limit && is_prime[x]) ++cnt;
    cout << cnt << '\n';
    return 0;
}