import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

    static int howManyGames(int p, int d, int m, int s) {
        // Return the number of games you can buy
        int totalAmountSpent=0;
        int numberOfTimesdUsed=0;
        int numberOfItemsPurchased=0;
        if(p<=s)
        {
            totalAmountSpent = totalAmountSpent+p;
            numberOfItemsPurchased = numberOfItemsPurchased+1;
        
        while(totalAmountSpent<=s)
        {
            numberOfTimesdUsed = numberOfTimesdUsed +1;
            if((p-(d*numberOfTimesdUsed)) >=m)
            {
                if((totalAmountSpent +(p-(d*numberOfTimesdUsed)))<=s)
                {
                    totalAmountSpent = totalAmountSpent +(p-(d*numberOfTimesdUsed));
                    numberOfItemsPurchased = numberOfItemsPurchased+1;
                }
                else
                {
                    break;
                }
            }
            else
            {
                if((totalAmountSpent + m)<=s)
                {
                    totalAmountSpent = totalAmountSpent + m;
                    numberOfItemsPurchased = numberOfItemsPurchased+1;
                }
                else
                {
                    break;
                }
            }
        }
        }
        return numberOfItemsPurchased;
    }

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int p = in.nextInt();
        int d = in.nextInt();
        int m = in.nextInt();
        int s = in.nextInt();
        int answer = howManyGames(p, d, m, s);
        System.out.println(answer);
        in.close();
    }
}