#include <bits/stdc++.h>
using namespace std;

int n, m, a, t;
bool f[200001];

int main() {
	cin >> n >> m;

	for (int i = 0; i < m; i++) {		
		cin >> a;
		f[a] = 1;
	}

	for (int i = n; i > 0; i--) {
		int u = n / i;

		if ((u & 1) ^ f[i]) {
			t++;

			for (int j = 1; j < sqrt(i); j++) {
				if (i % j == 0) {
					f[j] = 1 - f[j];
					f[i / j] = 1 - f[i / j];
				}
			}

			int k = (int)sqrt(i);

			if (k * k == i) {
				f[k] = 1 - f[k];
			}
		}
	}

	cout << t << endl;
}