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 min = Math.min(a,b);
    	int max = Math.max(a,b);
    	int h = max - min;
    	int ans = 2*min - h;
    	if(ans < 0) ans *= -1;
    	System.out.println(a == b?0:ans);
    }
}