import java.util.*;
public class Test9 {
  public static void main(String[] args){
    Scanner sc=new Scanner(System.in);
    String[] line;
    line=sc.nextLine().split(" ");
    int a=Integer.parseInt(line[0]);
    int b=Integer.parseInt(line[1]);
    int c=Integer.parseInt(line[2]);
    int d=Integer.parseInt(line[3]);
    int eat,tmp;
    eat=a;
    tmp=b/c;
    if(tmp<eat) eat=tmp;
    tmp=d/(1+c);
    if(tmp<eat) eat=tmp;
    System.out.println(eat);
  }
}