#include <bits/stdc++.h>
using namespace std;
#define chmax(x, y) x = max(x, y)
int main(){
    int a, b, c, d;
    cin >> a >> b >> c >> d;
    int ans = 0;
    for(int i = 1; i <= a; ++i){
        int foo = i * c;
        if(foo > b) continue;
        if(foo + i > d) continue;
        chmax(ans, i);
    }
    cout << ans << endl;
}