#include <iostream>
using namespace std;
int X, Y;
int main() {
	cin >> X >> Y;
	if (X == Y) cout << 0 << endl;
	else if (Y == 0) cout << 1 << endl;
	else if (X == 0) cout << 2 << endl;
	else if (X == -Y) cout << 3 << endl;
	else cout << -1 << endl;
	return 0;
}