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

int main(){
    int A,B,C,D;
    cin >> A >> B >> C >> D;
    int E=0;
    int M =0,V=0;
    if(B/A>C){
        cout << min(A,D/(C+1));
    }else{
        cout << min(B/C,D/(C+1));
    }

}