题解 | 求平均年龄

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int sum = 0;

        for (int i = 0; i < n; i++) {
            int number = scanner.nextInt();
            sum += number;
        }

        System.out.printf("%.2f", sum * 1.0 / n);
    }
}