课后练习3.

3.电信运营商客服电话

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication11
{
class Program
{
static void Main(string[] args)
{
Console.Write("请输入运营商客服电话");
string a = Console.ReadLine();

switch (a)
{

case "10000":
Console.WriteLine("中国电信");
break;

case "10010":
Console.WriteLine("中国联通");
break;

case "10086":
Console.WriteLine("中国移动");
break;

default:
Console.WriteLine("您输入有误");
break;

}

Console.ReadLine();

}
}
}

课后练习3.

原文：http://www.cnblogs.com/myspace2015/p/4694638.html