package yukicoder;
import java.util.Scanner;
public class Study {
	public static void main(String[] args) {
         Scanner sc = new Scanner(System.in);
         int a = sc.nextInt();
         int b = sc.nextInt();
         int c = 0;
         int d = 0;
         if(a>b){
        	c = 2000000000-a - 1;
        	d = 2000000000-b - 1;
        	if(c > d){
        		System.out.println(c);
        	}else if(c < d){
        		System.out.println(d);
        	}
        }else if(a < b){
        	c = b - a - 1;
        	d = a-1;
        	System.out.println(c + d);
        }
	}
}