#include <bits/stdc++.h>
using namespace std;

int main() {
    int p,d,m,s;
    cin>>p>>d>>m>>s;
    int count=0;
    while(s>=0){
        if(p>m){
        s=s-p;
        p=p-d;
        count++;
        }
        else{
            s=s-m;
            count++;
        }
    }
    cout<<count-1;
    return 0;
}