// stand alone version of j.n.magee 11/11/96
// by mh 19/03/03
// only textuell user interface

class Counter {

    int value=0;

    Counter(int init) {
        value = init;
    }

    void increment() {
        int temp = value;   	//read[v]
        Simulate.interrupt();
        value=temp+1;      	//write[v+1]
    }

    int get () {
        return value;
    }

} // class Counter


class Simulate {
    public static void interrupt() {
        if (Math.random() < 0.4)
           try { Thread.sleep(200);} catch(InterruptedException e){};
            //used instead of Thread.yield() to ensure portability
    }
} // class Simulate


class Turnstile extends Thread {
    
    Counter people;

    Turnstile (Counter c) { 
        people = c; 
    }

    public void run() {
      for (int i=1;i<=GardenTui.MAX;i++){
        people.increment();
      }
    }

} // class Turnstile
    

public class GardenTui {

    final static int MAX = 20;

    public static void main (String[] argv) {

        Counter counter = new Counter(0);

	Turnstile west= new Turnstile(counter);
        Turnstile east= new Turnstile(counter);
        west.start();
        east.start();

        try {
            west.join();	
            east.join(); 
            System.out.println("total count: " + counter.get());
        } catch (Exception e) {}

    } 

} // class GardenTui