using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
class Solution {

    static int howManyGames(int p, int d, int m, int s)
    {
        // Return the number of games you can buy
        bool first = true;
        int count = 0;
        int total = 0;
        for(;;)
        {
            if (p > m)
            {
                total = total + p;
                p = p - d;
                count++;                
            }
            else
            {
                total = total + m;
                count++;
            }
            if (total > s)
            {
                count--;
                break;
            }
        }
        return count;

    }

    static void Main(String[] args) {
        string[] tokens_p = Console.ReadLine().Split(' ');
        int p = Convert.ToInt32(tokens_p[0]);
        int d = Convert.ToInt32(tokens_p[1]);
        int m = Convert.ToInt32(tokens_p[2]);
        int s = Convert.ToInt32(tokens_p[3]);
        int answer = howManyGames(p, d, m, s);
        Console.WriteLine(answer);
    }
}