import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        int c = sc.nextInt();
        int d = sc.nextInt();
        
        int min1 = a;
        int min2 = b/c;
        int min3 = d/(c+1);
        
        int ans = Math.min(min1, Math.min(min2, min3));
        
        System.out.println(ans);
    }
}