const int N=10;
int countvalues = 1;

monitor monitor1
{
    int buffer[N];
    int write_pos;
    int read_pos;
    int count;
    condition full,empty;

    void queue_add(int item)
    {

        if(count == N)
        {
            waitc(full);
        }


        buffer[write_pos] = item;
        write_pos = (write_pos + 1) % N;
        count++;

        signalc(empty);

    }


    int queue_get()
    {
        int item;

        if(count == 0)
        {
            waitc(empty);
        }

        item = buffer[read_pos];
        read_pos = (read_pos + 1) % N;
        count--;
        countvalues++;
        signalc(full);
        return item;
    }

    init
    {
        read_pos = 0;
        write_pos = 0;
        count = 0;
    }

}

void producer(int size)
{
    int i;

    for(i=0; i<size; i++)
    {
            queue_add(i);

    }
}



void consumer(int size)
{
    int i;

    for(i=0; i<size; i++)
    {
        cout<<"Value number "<<countvalues<<": "<<queue_get()<<endl;
    }
}


main()
{
    cout<<"N="<<N<<endl;
    cout<<endl;
    cobegin
    {
        producer(N);
        producer(N);
        producer(N);
        consumer(3*N);
    }

    cout<<"All values consumed."<<endl;
}