Racer.java

public class Racer implements Runnable {

     int d = 42;

     public void run () {
          doSomething(1001);                   // (1)
          d = 0;                               // (2)
     }

     public static void main (String[] args){
          Racer racer = new Racer();
          Thread t = new Thread(racer);
          t.start();

          doSomething(1000);                   // (3)
          int c = 420 / racer.d;               // (4)
          System.out.println(c);
     }
     
     static void doSomething (int n) {
          // not very interesting..
          try { Thread.sleep(n); } catch (InterruptedException ix) {}
     }
}