#include<iostream>
#include<fstream>
using namespace std;

ifstream aa("light2.in");
ofstream ss("light2.out");
long long n,i,k,x[22],sum,j;
bool y[1000000001];
int main() {
	aa >> n >> k;
	for(i=1;i<=k;++i) {
		aa >> x[i];
		for(j=x[i];j<=n;j+=x[i]) {
			if (!y[j]) {
				y[j]=true;
				++sum;
			}
			else {
				y[j]=false;
				--sum;
			}
		}
	}
	ss << sum;
	return 0;
}