#include <bits/stdc++.h>

using namespace std;

int howManyGames(int p, int d, int m, int s) {
    int ct=0;
    while(s>=p&&s>=m)
    {
        ct++;
        s-=max(m,p);
        p=p-d;
    }
    return ct;
}

int main() {
    int p;
    int d;
    int m;
    int s;
    cin >> p >> d >> m >> s;
    int answer = howManyGames(p, d, m, s);
    cout << answer << endl;
    return 0;
}