#include<bits/stdc++.h>
using namespace std;
int main(){
    int a,b,c,d;cin>>a>>b>>c>>d;
    for(int i=1;i<=a;i++){
        if(i*c>b){
            cout<<i-1<<endl;
            return 0;
        }
        if(i+c*i>d){
            cout<<i-1<<endl;
            return 0;
        }
    }
    cout<<a<<endl;
}