346. Moving Average from Data Stream

/*
 * 346. Moving Average from Data Stream
 * 2016-7-11 by Mingyang
 * 这里注意的就是(double) sum / count
 * sum需要转换成double才能继续往下除，因为不转的话最后不能成为整数14除以3等于4
 */
class MovingAverage {
    public Queue<Integer> queue;
    public int sum = 0;
    public int si;
    public int count = 0;

    /** Initialize your data structure here. */
    public MovingAverage(int size) {
        this.si = size;
        queue = new LinkedList<Integer>();
    }

    public double next(int val) {
        if (queue.size() < si) {
            queue.add(val);
            sum += val;
            count++;
        } else {
            int temp = queue.poll();
            sum -= temp;
            queue.add(val);
            sum += val;
        }
        return (double) sum / count;
    }
}