#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <cmath>
#include <tuple>
#include <bitset>

#define rep(i,n) for(i=0; i<n; ++i)
#define dec_rep(i,n) for(i=n; i>=0; --i)
#define in(a) cin >> a
#define out(a,b) cout << a << b
#define print_vec(v) for(auto it=v.begin();it!=v.end();++it)cout<<*it <<" ";cout<<endl
#define print_vec2d(v) for(int i=0;i<v.size();++i){for(int j=0;j<v[i].size();++j)cout<<v[i][j]<<" ";cout<<endl;}cout<<endl
using namespace std;
using lint = long long;

int main(void){
    lint i, j, k, cnt=0, x, y;
    lint p, n, m;
    in(n); in(m);
    vector<bool> v(n,false);
    rep(i,m){
        in(k);
        v[k-1]=true;
    }
    dec_rep(i,n-1){
        if(v[i]){
            rep(j,i+1){
                if((i+1)%(j+1)==0){
                    v[j].flip();
                }
            }
        }
        else    cnt++;
    }
    out(cnt,endl);
    return 0;
}