#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define endl "\n"
#define rep(i, a, n) for (int i = a; i < n; ++i)

int main() {
    int a, b, c, d;
    cin >> a >> b >> c >> d;

    cout << min(a, min(b /c, d / (c + 1))) << endl;
    return 0;
}