public class concurrent {
    volatile static int x;
    public static void test(ExecutorService pool) throws  Exception{
        x = 1;
        Future<Integer> f1 = pool.submit(() -> x = x + 1);
        Future<Integer> f2 = pool.submit(() -> x = x * 5);
        f2.get();
        f1.get();
    }
    public static void main(String[] args) throws  Exception {
        Set<Integer> set  =  new HashSet<>();
        ExecutorService pool =  Executors.newFixedThreadPool(3);
        for(int i = 0 ;i < 100_000_000; i++){
            test(pool);
            set.add(x);
        }
        for(Integer e:set){
            System.out.println(e);
        }
        pool.shutdown();
    }

}