#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < n; ++i)
typedef long long ll;
using namespace std;

int main() {
    cin.tie(0);
    ios_base::sync_with_stdio(false);

    int N, M;
    cin >> N >> M;
    vector<int> P(N + 1);
    rep(i, M) {
        int a;
        cin >> a;
        P[a] = 1;
    }

    int ans = N;
    for (int i = N; i >= 1; --i) {
        if (P[i]) {
            for (ll j = 1; j * j <= i; ++j) {
                if (i % j == 0) {
                    P[j] ^= 1;
                    if (j * j != i)
                        P[i / j] ^= 1;
                }
            }
            ans--;
        }
    }
    cout << ans << "\n";

    return 0;
}