火车票身份证号的打码真不靠谱！

今天坐火车，发现火车票上的身份证号仅仅把出生月日这四位打了码，满打满算不超过 400 种可能性。
另外，最后一位校验码也没有打码，感觉又可以排除不少。

回来简单写了个脚本，验证了一下。发现加上校验码，最终只有不超过 40 种可能性（试了好几个身份证号）。
这码打的，跟没打差不多了。

附上代码：

#!/usr/bin/env python3
# -*- encoding: utf-8 -*-

def ID_number_check(num_in):
    if len(num_in) != 18:
        return False
    try:
        int(num_in[:17])
    except:
        return False
    check_num=num_in[-1]
    total_sum=int(num_in[0])*7+int(num_in[1])*9+int(num_in[2])*10+int(num_in[3])*5+int(num_in[4])*8+int(num_in[5])*4+int(num_in[6])*2+int(num_in[7])*1+int(num_in[8])*6+int(num_in[9])*3+int(num_in[10])*7+int(num_in[11])*9+int(num_in[12])*10+int(num_in[13])*5+int(num_in[14])*8+int(num_in[15])*4+int(num_in[16])*2
    remain=total_sum%11
    if remain == 0:
        check=1
    elif remain == 1:
        check=0
    elif remain == 2:
        check='X'
    elif remain == 3:
        check=9
    elif remain == 4:
        check=8
    elif remain == 5:
        check=7
    elif remain == 6:
        check=6
    elif remain == 7:
        check=5
    elif remain == 8:
        check=4
    elif remain == 9:
        check=3
    elif remain == 10:
        check=2
    if str(check_num) == str(check):
        return True
    else:
        return False

def ID_number_guess(num_in):
    num_in=num_in.upper()
    if len(num_in) != 18:
        print('请输入 18 位身份证号')
        exit(1)
    part1=num_in[:10]
    part2=num_in[-4:]
    year=num_in[6:10]
    Mons=range(1, 13)
    for Mon in Mons:
        if Mon in [1, 3, 5, 7, 8, 10, 12]:
            Days=range(1, 32)
        elif Mon == 2 and leap_year_check(year):
            Days=range(1, 30)
        elif Mon == 2 and not leap_year_check(year):
            Days=range(1, 29)
        else:
            Days=range(1, 31)
        if len(str(Mon)) == 1:
            Mon='0' +str(Mon)
        for Day in Days:
            if len(str(Day)) == 1:
                Day='0' +str(Day)
            num_out=part1 +str(Mon) +str(Day) +part2
            if ID_number_check(num_out):
                print(num_out)

def leap_year_check(year):
    try:
        year=int(year)
    except:
        return False
    if year % 400 == 0:
        return True
    elif year % 100 != 0 and year % 4 == 0:
        return True
    else:
        return False

if __name__ == '__main__':
    ID_number=input('请输入要猜测的身份证号: ')
    ID_number_guess(ID_number)

15015613

2017-01-18 18:46:13 +08:00

效果（身份证号从网上随便找的）：
```
请输入要猜测的身份证号: 5301021920****011x
53010219200102011X
53010219200110011X
53010219200129011X
53010219200209011X
53010219200217011X
53010219200225011X
53010219200305011X
53010219200313011X
53010219200321011X
53010219200401011X
53010219200428011X
53010219200508011X
53010219200516011X
53010219200524011X
53010219200604011X
53010219200612011X
53010219200620011X
53010219200719011X
53010219200727011X
53010219200807011X
53010219200815011X
53010219200823011X
53010219200831011X
53010219200903011X
53010219200911011X
53010219201009011X
53010219201017011X
53010219201025011X
53010219201105011X
53010219201113011X
53010219201121011X
53010219201201011X
53010219201228011X
```