编辑代码

using System;

public class HelloWorld
{
    public static void Main()
    {
       int a, x = 0;
        Console.WriteLine("请输入一个五位数：");
        a = Convert.ToInt32(Console.ReadLine());
        int b = a;
        int c=1;
        if (a > 9999 && a < 100000)
        {
            c = 0;

        }

        for (; c == 1;)

        {
            Console.WriteLine("输入数字应为五位数，请重新输入：");
            a = Convert.ToInt32(Console.ReadLine());
            if (a > 9999 && a < 100000)
                break;

        }
        for (; b > 0; b = b / 10)
        {
            x = x * 10 + b % 10;

        }
        Console.WriteLine("五位数{0}的逆序数为：{0}", a, b);
    }

    
}