#include <bits/stdc++.h>

using namespace std;

int howManyGames(int p, int d, int m, int s) {
    // Return the number of games you can buy
    int sum=0,count=0,x;
    for(int i=0;sum<=s;i++)
    {
        
        x=p-d*i;
        
        //cout<<x<<" ";
        if(x>=m)
        sum+=p-d*i;
        else
            sum+=m;
        //cout<<sum<<" ";
        if(sum<=s)
            count++;
    }
    return count;
}

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;
}