#include "bits/stdc++.h"
using namespace std;
typedef long long ll;
void Say(bool say, string a = "Yes", string b = "No"){cout << (say ? a : b) << endl;};

int main(){
    ll A, B, C, D;
    cin >> B >> A >> C >> D;
    ll ans = 0;
    for(ll i = 0; i <= B; i++){
        if(C * i <= A && C * i + i <= D)ans = i;
    }
    cout << ans << endl;
    return 0;
}