import java.util.Scanner;

public class GetPointOnCircle {
    public static void log(Object obj) {
        System.out.println(obj.toString());
    }
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        if(a>b) {
            int g = b;
            b=a;
            a=g;
        }
        if(4<=a) {
            log(a-4);
        } else {
            log(b+4);
        }
    }
}