Method add

lowlevel/CircularSet.java:19–23

(int i)

    Arrays.fill(array, -1);
  }
  public synchronized void add(int i) {
    array[index] = i;
    // Wrap index and write over old elements:
    index = ++index % size;
  }
  public synchronized boolean contains(int val) {
    for(int i = 0; i < size; i++)
      if(array[i] == val) return true;