#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using P = pair<int, int>;
using PL = pair<ll, ll>;
// Welcome to my source code!

int main() {
    int a, b, c, d;
    cin >> a >> b >> c >> d;
    int ans = 0;
    for (int i = 1; i <= a; i++) {
        int j = i * c;
        if (j <= b && i + j <= d) ans = i;
    }
    cout << ans << endl;
}