Moving Average of An Input Stream

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Moving Average of An Input Stream. The size of a window is n
For example:
input = [1, 1, 2, 3, 3, 4, 4, 4, 5.....], n = 3;
moving average = [1, 1, 1.33, 2, 2.67, 3.33, 3.67, 4, 4.33...]

public void movingAverage(Stream input, int windowSize)

最下面的做法不是动态的，改为如下，同时也得改之前的另一道题。

public class MovingAverage {    Queue<Integer> list;    int size = 0;    int sum = 0;    /** Initialize your data structure here. */    public MovingAverage(int size) {        list = new LinkedList<>();        this.size = size;    }        public double next(int val) {        double result = 0.0;        if (list.size() < size) {            sum = sum + val;            list.offer(val);            result = (double)sum / list.size();        } else {            int deletedNum = list.poll();            sum = sum - deletedNum;            sum = sum + val;            result = (double)sum / size;            list.offer(val);        }        return result;    }}/** * Your MovingAverage object will be instantiated and called as such: * MovingAverage obj = new MovingAverage(size); * double param_1 = obj.next(val); */

import java.text.DecimalFormat;public class MovingAverage {private static DecimalFormat df2 = new DecimalFormat(".##");public static void main(String[] args) {// TODO Auto-generated method stubint[] array = {1, 1, 2, 3, 3, 4, 4, 4, 5};double[] arrays = movingAverage(array, 3);for (double d: arrays) {//System.out.format("%.2f",d);//System.out.println("");System.out.println(df2.format(d));}}private static double[] movingAverage(int[] array, int n) {double[] res = new double[array.length];int sum = 0;for (int i = 0; i < array.length; i++) {if (i < n) {sum = sum + array[i];res[i] = (double)sum/(i + 1);} else {sum = sum - array[i - n];sum = sum + array[i];res[i] = (double)sum/n;}}return res;}}

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