#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <stack>
#include <queue>
#include <list>
#include <set>
#include <map>
#include <numeric>
#include <regex>
#include <tuple>
#include <iomanip>
#include <cmath>
using namespace std;

typedef long long ll;
typedef pair<int, int> P;
#define MOD 1000000007 // 10^9 + 7
#define INF 1000000000 // 10^9
#define LLINF 1LL<<60


int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);

	int X, Y; 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;
}