Moving Average from Data Stream -- LeetCode
Given a stream of integers and a window size, calculate the moving average of all integers in the sliding window.
For example,
MovingAverage m = new MovingAverage(3);
m.next(1) = 1
m.next(10) = (1 + 10) / 2
m.next(3) = (1 + 10 + 3) / 3
m.next(5) = (10 + 3 + 5) / 3
1 class MovingAverage {
2 private:
3 queue<int> numsInWindow;
4 int windowSize;
5 double lastAverage;
6 public:
7 /** Initialize your data structure here. */
8 MovingAverage(int size) {
9 windowSize = size;
10 }
11
12 double next(int val) {
13 if (numsInWindow.empty()) {
14 numsInWindow.push(val);
15 lastAverage = (double) val;
16 }
17 else if (numsInWindow.size() < windowSize) {
18 double total = lastAverage * numsInWindow.size();
19 numsInWindow.push(val);
20 lastAverage = (total + val) / numsInWindow.size();
21 }
22 else {
23 double total = lastAverage * numsInWindow.size();
24 total -= numsInWindow.front();
25 numsInWindow.pop();
26 numsInWindow.push(val);
27 lastAverage = (total + val) / numsInWindow.size();
28 }
29 return lastAverage;
30 }
31 };
32
33 /**
34 * Your MovingAverage object will be instantiated and called as such:
35 * MovingAverage obj = new MovingAverage(size);
36 * double param_1 = obj.next(val);
37 */
