import java.io.*;
import java.util.*;

public class Solution {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        long n = in.nextInt();
        long c = in.nextInt();
        long u = in.nextInt();
        long s = in.nextInt();
        long n2 = n;
        long c2 = c;

        long max, count3;
        long count1 = c/u;
//         int i = 0;
//         while(u*n > c){
//             n--;
//             c+=s;
//             long x = c/u;
//             if(n<c) {
//                 break;
//             }

//         }
        n2 = n-count1;
        long remainingC = c%u;
        long upgradabel = 0;
        do{
            while(remainingC<u){
                n2--;
                remainingC+=s;
            }
            count1++;
            System.out.println(count1);
            remainingC-=u;
            if(u>remainingC) break;
            if(n2<0) break;
        }while(true);

        long count2 = c2/u;
        count3 =count1 + count2;

        if(count3>n) max=count3;
        else max=n;
        System.out.println(count1);

    }
}