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

#ifdef _RUTHEN
#include "debug.hpp"
#else
#define show(...) true
#endif

using ll = long long;
#define rep(i, n) for (int i = 0; i < (n); i++)
template <class T> using V = vector<T>;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int N, M;
    cin >> N >> M;
    V<int> A(N + 1, 0);
    rep(i, M) {
        int a;
        cin >> a;
        A[a] = 1;
    }
    V<V<int>> G(N + 1);
    for (int i = 1; i <= N; i++) {
        for (int j = 2 * i; j <= N; j += i) {
            G[j].push_back(i);
        }
    }
    int ans = 0;
    for (int i = N; i > 0; i--) {
        if (A[i] == 0) {
            ans++;
        } else {
            for (auto j : G[i]) A[j] ^= 1;
        }
    }
    cout << ans << '\n';
    return 0;
}