Mutator Methods

public class Stat {
    private int total = 0;
    private int count = 0;
    public void add(int v) {
        total += v;
        count++;
    }
    public double avg() {
        if (count == 0) return 0;
        return (double) total / count;
    }
}
// ...
Stat s = new Stat();
s.add(2); s.add(4); s.add(6);
System.out.println(s.avg());

• A

  0.0

• B

  3.0

• C

  4.0

  check_circle
• D

  12.0