#include <bits/stdc++.h>

using namespace std;

int howManyGames(int p, int d, int m, int s) {
    int k = (p-m)/d;
    int count=0,i=1,sum=0,temp;
   // if((p-m)%d!=0) k=k+1;
   while(1){
       if(p-d*(i-1)>=m) temp=p-d*(i-1);
       else temp=m;
       
      // cout<<temp<<" ";
       sum=sum+temp;
       if(sum<=s) count++;
       else break;
       i++;
   }
    
    return count;
    
    
    // Return the number of games you can buy
}

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;
}