import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		int X = scan.nextInt();
		int Y = scan.nextInt();
		scan.close();
		if(X == Y) {
			System.out.println(0);
		}else if(Y == 0) {
			System.out.println(1);
		}else if(X == 0) {
			System.out.println(2);
		}else if(X == -Y) {
			System.out.println(3);
		}else {
			System.out.println(-1);
		}
	}
}