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 cnt=0;
    double avg=0;
    double sum=0;
    while(scan.hasNext()){
        int num=scan.nextInt();
        if(num<0){
            break;
        }
        sum+=num;
        cnt++;
    }
    avg=sum/cnt;

System.out.println(String.format("%.2f",avg));

}

}