#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


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