#include <bits/stdc++.h>

using namespace std;

int howManyGames(int p, int d, int m, int s) {
    int ans = 0;
    bool done = false;
    while(!done) {
        
        if(p > m) {
            if(s >= p) {
            s -= p;
            p -= d;
            ans++;
            } else {
                done = true;
            }
        } else {
            if(s >= m) {
                s -= m;
                ans++;
            } else {
                done = true;
            }
            
        }
        
    }
    return ans;
}

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;
}