import java.util.concurrent.locks.*;


class MinMonitor {

    int verdi;
    Lock laas = new ReentrantLock();

    public MinMonitor(int startVerdi){
        verdi = startVerdi;
    }

    public void leggPaa(int tall){

        laas.lock();
        try {
            int nyVerdi = verdi;
            nyVerdi = nyVerdi + tall;
            Thread.sleep(1);
            verdi = nyVerdi;
        }
        catch(Exception e){

        }
        finally{
            laas.unlock();
        }

    }

    public void trekkFra(int tall){

        laas.lock();
        try {
            int nyVerdi = verdi;
            nyVerdi = nyVerdi - tall;
            try {
                Thread.sleep(1);
            }
            catch(Exception e){}
            verdi = nyVerdi;
        }
        finally{
            laas.unlock();
        }
    }


    public int hentVerdi(){
        return verdi;
    }
}