#include <bits/stdc++.h>
#define mp make_pair
#define all(vec) vec.begin(), vec.end()
using namespace std;
using ll = long long;
using P = pair<ll, ll>;
const ll INF = 1LL << 30;
const ll LINF = 1LL << 60;
const double eps = 1e-9;
const ll MOD = 1000000007LL;
int main() {
    int a, b, c, d;
    cin >> a >> b >> c >> d;
    int ans = 0;
    for(int i = 0; i <= a; i++) {
        if(i * c > b) continue;
        if(i * (c + 1) > d) continue;
        ans = i;
    }
    cout << ans << endl;
}