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

int main()
{
	int n, a, b, c;

	cin >> n;
	cin >> a >> b >> c;

	int ans;

	ans = n / a + n / b + n / c;
	ans = ans - n / (a*b) - n / (b*c) - n / (a*c);
	ans += n / (a*b*c);

	cout << ans << endl;

	return 0;
}