Core Computer Science

class Stop
{
    private String str;
    protected void finalize() { System.out.print(str); }
    public Stop(String s) {str = s;}
}

class Flow
{
    private static void func(Stop[] stop)
    { stop[0] = stop[1] = stop[2] = null; }
    public static void main(String[] args)
    {
        Stop[] stop = new Stop[3];           // Line 1
        stop[0] = new Stop("x");             // Line 2
        stop[1] = new Stop("y");             // Line 3
        stop[2] = new Stop("z");             // Line 4
        func(stop);
        System.gc();
    }
}