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

void solve() {
    int A, B, C, D;
    cin >> A >> B >> C >> D;
    int ans = D / (C + 1);
    ans = min(ans, A);
    ans = min(ans, B / C);
    cout << ans << endl;
    return;
}

int main() {
    solve();
}