#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>

int howManyGames(int p, int d, int m, int s) {
    int i=0,count = 0;
    while(1){
        if(p-i*d > m){
            if(s - (p-i*d) >=0){
                count++;
                s -= p-i*d;
            }else{
                break;
            }
        }else{
            if(s - m >=0){
                count++;
                s -= m;
            }else{
                break;
            }
        }
        i++;
    }
    return count;
}

int main() {
    int p; 
    int d; 
    int m; 
    int s; 
    scanf("%i %i %i %i", &p, &d, &m, &s);
    int answer = howManyGames(p, d, m, s);
    printf("%d\n", answer);
    return 0;
}