题解 | #求平均数#

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        double sum = 0;//若sum设置为int注意强转
        double avg = 0;
        int number;
        for (int i = 1;; i++) { 
		  //这里用i计数
            number = scan.nextInt();
            if (number <= 0) {
                break;
            }
            sum += number;
            avg = sum / i;
        }
        System.out.println(String.format("%.2f", avg));
    }
}