#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using P = pair<ll,ll>;
#define fix(x) fixed << setprecision(x)
#define asc(x) x, vector<x>, greater<x>
#define rep(i, n) for(ll i = 0; i < n; i++)
#define all(x) (x).begin(),(x).end()
template<class T>bool chmin(T&a, const T&b){if(a>b){a=b;return 1;}return 0;}
template<class T>bool chmax(T&a, const T&b){if(a<b){a=b;return 1;}return 0;}

int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    int n,m;
    cin >> n >> m;
    vector<bool> b(n+1,false);
    rep(i,m){
        int a;
        cin >> a;
        b[a] = true;
    }
    int ans = 0;
    for(int i=n;i>=1;i--){
        if(!b[i]){
            ans++;
        }
        else{
            for(int j=1;j*j<=i;j++){
                if(!(i%j)){
                    b[j] = !b[j];
                    if(j*j!=i) b[i/j] = !b[i/j];
                }
            }
        }
    }
    cout << ans << '\n';
    return 0;
}