I know a way to find the angle difference of two angles between [0,180], but I'm trying to find out a way to find the angle difference of two angles between [-179,180].

My code is as follows; it doesn't work properly:

```
private int distance2(int alpha, int beta) {
    int phi = beta - alpha;// % 360;    // This is either the distance or 360 - distance
    int distance = 0;
    if (phi < -360) {
        distance = 360 + phi;
    } // end of if
    else{
        distance = phi;  
    }
    return distance;
}

```