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

    }
}