#include<iostream>
#include<string>
#include<algorithm>
#include<cctype>
#include<set>
#include<bitset>
#include<math.h>
#include<map>
#include<queue>
#include<iomanip>
using namespace std;

int main(){
    int a, b, c, d;
    cin >> a >> b >> c >> d;
    cout << min({a, b/c, d/(c+1)}) << endl;
}