#include <iostream>
#include <cmath>
using namespace std;

int main() {
    long long Gx, Gy;
    cin >> Gx >> Gy;
    
    if (Gx == 0 && Gy == 0) {
        cout << 0 << endl;
        return 0;
    }
    
    // ルークの場合の手数
    int rook_moves;
    if (Gx == 0 || Gy == 0) {
        rook_moves = 1;
    } else {
        rook_moves = 2;
    }
    
    int bishop_moves;
    if (abs(Gx) == abs(Gy)) {
        bishop_moves = 1;
    } else if ((Gx + Gy) % 2 == 0) {
        bishop_moves = 2;
    } else {
        bishop_moves = -1;
    }
    
    if (bishop_moves == -1) {
        cout << rook_moves << endl;
    } else {
        cout << min(rook_moves, bishop_moves) << endl;
    }
    
    return 0;
}