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

int main() {
    int n;
    cin >> n;
    int a, b, c;
    cin >> a >> b >> c;
    cout << (n / a + n / b + n / c - n / a / b - n / b / c - n / c / a + n / a / b / c) << endl;
}