import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

public class Monitor {
	private int teller = 0;
	Lock l?s = new ReentrantLock();

	public void ?k() {
		l?s.lock();
		try {
			teller++;
		} finally {
			l?s.unlock();
		}
	}

	public void printTall() {
		l?s.lock();
		try {
			System.out.println(teller);
		} finally {
			l?s.unlock();
		}
	}
}