import std.stdio, std.string, std.conv;
import std.range, std.algorithm, std.array;

void main() {
    int x,y;
    scan(x,y);

    int ans;

    if (x == y) {
        ans = 0;
    }
    else if (x != 0 && y == 0) {
        ans = 1;
    }
    else if (x == 0 && y != 0) {
        ans = 2;
    }
    else if (x == -y) {
        ans = 3;
    }
    else {
        ans = -1;
    }

    writeln(ans);
}





void scan(T...)(ref T args) {
    import std.stdio : readln;
    import std.algorithm : splitter;
    import std.conv : to;
    import std.range.primitives;

    auto line = readln().splitter();
    foreach (ref arg; args) {
        arg = line.front.to!(typeof(arg));
        line.popFront();
    }
    assert(line.empty);
}



void fillAll(R, T)(ref R arr, T value) {
    static if (is(typeof(arr[] = value))) {
        arr[] = value;
    }
    else {
        foreach (ref e; arr) {
            fillAll(e, value);
        }
    }
}