import java.util.concurrent.ConcurrentHashMap;

public class Task071125 {
    public static void main(String[] args) throws InterruptedException {
        ConcurrentHashMap<String, Integer> map = new ConcurrentHashMap<>();
        map.put("count", 0);

        Thread t1 = new Thread(() -> {
            for (int i = 0; i < 1000; i++) {
                map.computeIfPresent("count", (k, v) -> v + 1);
            }
        });

        Thread t2 = new Thread(() -> {
            for (int i = 0; i < 1000; i++) {
                map.put("count", map.get("count") + 1);
            }
        });

        t1.start();
        t2.start();
        t1.join();
        t2.join();

        System.out.println(map.get("count"));
    }
}