第二周

import java.util.Scanner;

public class Pest {
    public static void main(String[] args) {
        Scanner Lf=new Scanner(System.in);
        String LinF;
        System.out.println("请输入一个0-1000的整数来求整数各位数的和");
        LinF = Lf.nextLine();
        if(Integer.valueOf(LinF) <= 1000) {
            int a = 0;
            for (int i = 0; i < LinF.length(); i++) {
                a = a + Integer.valueOf(LinF.substring(i, i + 1));
            }
            System.out.println(a);
        }

    }
}