public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        System.out.println("请输入一个三位数");
        int n = scan.nextInt();
     //计算百位  十位 各位
        int b100 =n/100;
        int b10  =n/10%10;
        int b1   =n%10;
        int sum = b100+b10+b1;
        System.out.println(sum);
    }
}