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);

        //write your code here......
        

        //输出格式为：System.out.println(String.format("%.2f",avg));
        int sum =0;
        double count =0;
        while(true){
            int input = scan.nextInt();
            if(input<0){
                break;
            }
            sum += input;
            count++;
        }
        double avg = sum/count;
        System.out.println(String.format("%.2f",avg));

    }
}