#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

bool dp[10000];
bool so[10000];

void solve(int m, int cnt, vector<int> &c);

int res;
int main()
{
	for (int i = 2; i < 10000; i++) {
		so[i] = true;
	}
	for (int i = 2; i < 10000; i++) {
		if (so[i]) {
			for (int j = i + 1; j < 10000; j++) {
				if (so[j]) {
					if (!(j%i))so[j] = false;
				}
			}
		}
	}

	int m, n;
	cin >> m >> n;

	vector<int> c;
	c.resize(n);
	for (int i = 0; i < n; i++) {
		cin >> c[i];
	}
	sort(c.begin(), c.end());

	solve(m, 1, c);

	cout << res+(m/c[0]) << endl;

    return 0;
}

void solve(int m, int cnt, vector<int> &c) {
	for (int i = 0; i < c.size(); i++) {
		int mtmp;
		mtmp = m - c[i];
		if (mtmp <= 1) break;
		if (mtmp > 1) {
			if (!dp[mtmp])dp[mtmp] = true;
			else continue;

			if (so[mtmp]) {
				res += cnt;
				so[mtmp] = false;
			}
			solve(mtmp, cnt+1, c);
		}
	}
}