ex2_6.java

Introduction to java programming 一书中所有编程练习部分的源码

import javax.swing.JOptionPane;

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

/**
 *
 * @author xiaolei
 */
public class EX2_6 {

    public static void main(String[] args) {
        int num, sum = 0;
        num = Integer.parseInt(JOptionPane.showInputDialog("输入0-1000之间的整数："));
        if((num < 0) || (num > 1000)){
            JOptionPane.showMessageDialog(null, "错误的输入值："+num);
            System.exit(0);
        }
        while(num != 0){
            sum += num % 10;
            num = num / 10;
        }
        
        JOptionPane.showMessageDialog(null, "结果："+sum);
    }

}