Maintain a Windowed Moving Average across Stream Calls
Company: Spotify
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: easy
Interview Round: Other
### Problem
Implement MovingAverage(int size) and double next(int val). Each next call appends val and returns the mean of the most recent size values, or of all seen values while fewer than size have arrived. Preserve the persistent class API.
```cpp
class MovingAverage {
public:
MovingAverage(int size);
double next(int val);
};
```
### Examples
```text
MovingAverage(2); next(2) -> 2.0; next(6) -> 4.0; next(4) -> 5.0
MovingAverage(1); next(-3) -> -3.0; next(7) -> 7.0
```
### Constraints
- Window size is 1 through 1000.
- Values lie in [-100000,100000].
- At most 10000 next calls occur.
Overview: Maintain a Windowed Moving Average across Stream Calls. Implement MovingAverage(int size) and double next(int val). Each next call appends val and returns the mean of the most recent size values, or of all seen value