#include<iostream>
#include<string>
#include<math.h>
#include<stdlib.h>
#include<string>
using namespace std;


int main() {
	int a, b, c, d,e;
	cin >> a >> b >> c >> d;
	if (a * c >= b) {
		e = b;
	}
	else {
		e = a;
	}
	if (d / (1 + c) >e) {
		cout << e;
	}
	else {
		cout << d / (1 + c);
	}
	
}