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);
        float sum = 0, avg = 0;
        int count = 0;
        while (true) {
            int num = scan.nextInt();
            if (num < 0) {
                break;
            }
            sum = num + sum;
            count++;
        }
        avg = sum / count;

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


    }
}