#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf 1000000000


int main() {
    
	int n,m;
	cin>>n>>m;
	
	vector<int> f(n+1,0);
	rep(i,m){
		
		int a;
		cin>>a;
		f[a] = 1;
	}
	
	int ans = 0;
	for(int i=n;i>=1;i--){
		if(f[i]==0)ans++;
		else{
			
			for(int j=1;j*j<=i;j++){
				if(i%j==0){
					f[j] ^= 1;
					if(j*j!=i)f[i/j]^=1;
				}
			}
			
		}
	}
	
	cout<<ans<<endl;
	
    return 0;
}