#include <cstdio>
#include <cstring>
#include <iostream>
#include <string>
#include <cmath>
#include <bitset>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <algorithm>
#include <complex>
#include <unordered_map>
#include <unordered_set>
#include <random>
#include <cassert>
#include <fstream>
#define popcount __builtin_popcount
using namespace std;
typedef long long int ll;
typedef pair<int, int> P;

int main()
{
    int a, b, c, d; cin>>a>>b>>c>>d;
    int ans=0;
    for(int i=1; i<=a; i++){
        if(i*c>b) break;
        if(i+i*c>d) break;
        ans=i;
    }
    cout<<ans<<endl;
    return 0;
}