#include<bits/stdc++.h>
using namespace std;


int howManyGames(int p, int d, int m, int s) {
    int cnt = 0;
    while( s >= 0 )
    {
        s -= max(p,m);
        if( s >= 0 ) cnt++;
        p -= d;
    }
    return cnt;
}

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;
}