In my late night brainstorming, I wrote a small program that can calculate the ID number for train tickets.

1. The * number on the train ticket is the month and day. Theoretically, there are a maximum of 366 combinations; 2. The check code is the last digit, 0-9 and X, 11 results; 3. Then , through the ID number on the train ticket, you can get about 33 real valid ID numbers; 4. If you can know the other person’s zodiac sign (well, don’t everyone often reveal what zodiac sign they are), then,

1. The * number on the train ticket indicates the month and day. In theory, there are a maximum of 366 combinations;

2. The check code is the last digit, 0-9 and X, 11 results;

3. Then, through the ID number on the train ticket, you can get about 33 real valid ID numbers;

4. If you can know the other person’s zodiac sign (well, don’t we often reveal what zodiac sign we are), then map these 30-plus results to 12 zodiac signs, and the final possibility is only 2-3 . . .

5. Conclusion: When posting tickets, be sure to code them

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

namespace Geyunfei.CheckID
{
    class PRogram
    {

        static int[] a = new int[] { 7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2 };
        static char[] b = new char[] { '1', '0', 'X', '9', '8', '7', '6', '5', '4', '3', '2' };
        static int index = 0;
        static void Main(string[] args)
        {

            System.Console.WriteLine("输入火车票上的身份证号:");

            String a = System.Console.ReadLine();
            var year = int.Parse(a.Substring(6, 4));
            var beginDate = new DateTime(year, 1, 1);
            var chk = a.Substring(14);

            int days = 365;
            if (DateTime.IsLeapYear(year))
                days++;
            for(int i =0;i<days; i++)
            {
                var chkDate = beginDate.AddDays(i).ToString("MMdd");
                var id = a.Substring(0, 10) + chkDate + chk;
                CheckID(id);

            }
           

        }

        private static void CheckID(string id)
        {
            int sum = 0;
            for(int i = 0; i < 17; i++)
            {
                sum += int.Parse(id[i].ToString()) * a[i];
            }
            var chk = b[sum % 11];
            if (chk == id[17])
            {
                index++;
                Console.WriteLine(getAstro(int.Parse(id.Substring(10,2)),int.Parse(id.Substring(12,2)))+ index.ToString() +" "+id);
            }
        }

        private static String getAstro(int month, int day)
        {
            String[] starArr = {"魔羯座","水瓶座", "双鱼座", "牡羊座",
        "金牛座", "双子座", "巨蟹座", "狮子座", "处女座", "天秤座", "天蝎座", "射手座" };
            int[] DayArr = { 22, 20, 19, 21, 21, 21, 22, 23, 23, 23, 23, 22 };  // 两个星座分割日
            int index = month;
            // 所查询日期在分割日之前，索引-1，否则不变
            if (day < DayArr[month - 1])
            {
                index = index - 1;
            }
            index = index % 12;
            // 返回索引指向的星座string
            return starArr[index];
        }

    }
}